From b478b10f34a9fa9c6b42f54047eb9e77111a16c7 Mon Sep 17 00:00:00 2001
From: Scott Main When a 3rd-party server posts a message to GCM and receives a message ID back,
-it does not mean that the message was already delivered to the device. Rather, it
-means that it was accepted for delivery. What happens to the message after it is
-accepted depends on many factors. When a 3rd-party server posts a message to GCM and receives a message ID back, it does not mean that the message was already delivered to the device. Rather, it means that it was accepted for delivery. What happens to the message after it is accepted depends on many factors. In the best-case scenario, if the device is connected to GCM, the screen is on, and there are no throttling restrictions (see Throttling), the message will be delivered right away. If the device is connected but idle, the message will still be
+delivered right away unless the In the best-case scenario, if the device is connected to GCM, the screen is on,
-and there are no throttling restrictions (see Throttling),
-the message will be delivered right away. Note: There is a limit on how many messages can be stored without collapsing. That limit is currently 100. If the limit is reached, all stored messages are discarded. Then when the device is back online, it receives a special message indicating that the limit was reached. The application can then handle the situation properly, typically by requesting a full sync. If the device is connected but idle, the message will still be
-delivered right away unless the Note: There is a limit on how many messages can
-be stored without collapsing. That limit is currently 100. If the limit is reached,
-all stored messages are discarded. Then when the device is back online, it receives
-a special message indicating that the limit was reached. The application can then
-handle the situation properly, typically by requesting a full sync.
- If the device is not connected to GCM, the message will be stored until a
-connection is established (again respecting the collapse key rules). When a connection
-is established, GCM will deliver all pending messages to the device, regardless of
-the Finally, when GCM attempts to deliver a message to the device and the
-application was uninstalled, GCM will discard that message right away and
-invalidate the registration ID. Future attempts to send a message to that device
-will get a Although is not possible to track the status of each individual message, the
-Google APIs Console stats are broken down by messages sent to device, messages
-collapsed, and messages waiting for delivery. If the device is not connected to GCM, the message will be stored until a connection is established (again respecting the collapse key rules). When a connection is established, GCM will deliver all pending messages to the device, regardless of the Finally, when GCM attempts to deliver a message to the device and the application was uninstalled, GCM will discard that message right away and invalidate the registration ID. Future attempts to send a message to that device will get a Although is not possible to track the status of each individual message, the Google APIs Console stats are broken down by messages sent to device, messages collapsed, and messages waiting for delivery. To prevent abuse (such as sending a flood of messages to a device) and
@@ -119,112 +74,107 @@ belonging to a non-throttled category by GCM for network and battery
efficiency reasons. Whenever the application registers as described in
-Implementing GCM Client,
-it should save the registration ID for future use, pass it to the
-3rd-party server to complete the registration, and keep track of
-whether the server completed the registration. If the server fails
-to complete the registration, it should try again or unregister from GCM. Whenever the application receives a There are also two other scenarios that require special care: When an application is updated, it should invalidate its existing registration
-ID, as it is not guaranteed to work with the new version. Because there is no
-lifecycle method called when the application is updated, the best way to achieve
-this validation is by storing the current application version when a registration
-ID is stored. Then when the application is started, compare the stored value with
-the current application version. If they do not match, invalidate the stored data
-and start the registration process again. Similarly, you should not save the registration ID when an application is
-backed up. This is because the registration ID could become invalid by the time
-the application is restored, which would put the application in an invalid state
-(that is, the application thinks it is registered, but the server and GCM do not
-store that registration ID anymore—thus the application will not get more
-messages). When an application is updated, it should invalidate its existing registration ID, as it is not guaranteed to work with the new version. Because there is no lifecycle method called when the application is updated, the best way to achieve this validation is by storing the current application version when a registration ID is stored. Then when the application is started, compare the stored value with the current application version. If they do not match, invalidate the stored data and start the registration process again. Similarly, you should not save the registration ID when an application is backed up. This is because the registration ID could become invalid by the time the application is restored, which would put the application in an invalid state (that is, the application thinks it is registered, but the server and GCM do not store that registration ID anymore—thus the application will not get more messages). On the server side, as long as the application is behaving well, everything
-should work normally. However, if a bug in the application triggers multiple
-registrations for the same device, it can be hard to reconcile state and you might
-end up with duplicate messages. GCM provides a facility called "canonical registration IDs" to easily
-recover from these situations. A canonical registration ID is defined to be the ID
-of the last registration requested by your application. This is the ID that the
-server should use when sending messages to the device. If later on you try to send a message using a different registration ID, GCM
-will process the request as usual, but it will include the canonical registration
-ID in the On the server side, as long as the application is behaving well, everything should work normally. However, if a bug in the application triggers multiple registrations for the same device, it can be hard to reconcile state and you might end up with duplicate messages. GCM provides a facility called "canonical registration IDs" to easily recover from these situations. A canonical registration ID is defined to be the ID of the last registration requested by your application. This is the ID that the server should use when sending messages to the device. If later on you try to send a message using a different registration ID, GCM will process the request as usual, but it will include the canonical registration ID in the When registration or unregistration fails, the app should retry the failed operation. In the simplest case, if your application attempts to register and GCM is not a
-fundamental part of the application, the application could simply ignore the error
-and try to register again the next time it starts. Otherwise, it should retry the
-previous operation using exponential back-off. In exponential back-off, each time
-there is a failure, it should wait twice the previous amount of time before trying
-again. If the register (or unregister) operation was synchronous, it could be retried
-in a simple loop. However, since it is asynchronous, the best approach is to schedule
-a {@link android.app.PendingIntent} to retry the operation.
-
- This section explains when you should unregister in GCM and what happens
-when you do. A registration ID (regID) represents a particular Android application running
-on a particular device. You should only need to unregister in rare cases, such as
-if you want an app to stop receiving messages, or if you suspect that the regID has
-been compromised. In general, though, once an app has a regID, you shouldn't need
-to change it. In particular, you should never unregister your app as a mechanism for
-logout or for switching between users, for the following reasons: When the application receives a In the simplest case, if your application just calls The back-off time is stored in a shared preference. This ensures that it is persistent across multiple activity launches. The name of the intent does not matter, as long as the same intent is used in the following steps. The solution is to manage your own mapping between users, the regID, and
-individual messages: Note: You must dynamically create a new instance of the broadcast receiver since the one defined by the manifest can only receive intents with the An application can be automatically unregistered after it is uninstalled from
-the device. However, this process does not happens right away, as Android does not
-provide an uninstall callback. What happens in this scenario is as follows: There are two ways to unregister a device from GCM: manually and automatically. An Android application can manually unregister itself by issuing a An application can be automatically unregistered after it is uninstalled from the device. However, this process does not happens right away, as Android does not provide an uninstall callback. What happens in this scenario is as follows: Note: The GCM client is the Google Cloud
-Messaging framework present on the device. Note: The GCM client is the Google Cloud Messaging framework present on the device. Note that it might take a while for the registration ID be completely removed
-from GCM. Thus it is possible that messages sent during step 7 above gets a valid
-message ID as response, even though the message will not be delivered to the device.
-Eventually, the registration ID will be removed and the server will get a
- Note that it might take a while for the registration ID be completely removed from GCM. Thus it is possible that messages sent during step 7 above gets a valid message ID as response, even though the message will not be delivered to the device. Eventually, the registration ID will be removed and the server will get a
Lifetime of a Message
-delay_while_idle flag is set to true. Otherwise, it will be stored in the GCM servers until the device is awake. And that's where the collapse_key flag plays a role: if there is already a message with the same collapse key (and registration ID) stored and waiting for delivery, the old message will be discarded and the new message will take its place (that is, the old message will be collapsed by the new one). However, if the collapse key is not set, both the new and old messages are stored for future delivery.delay_while_idle flag is set to true.
-Otherwise, it will be stored in the GCM servers until the device is awake. And
-that's where the collapse_key flag plays a role: if there is already
-a message with the same collapse key (and registration ID) stored and waiting for
-delivery, the old message will be discarded and the new message will take its place
-(that is, the old message will be collapsed by the new one). However, if the collapse
-key is not set, both the new and old messages are stored for future delivery.
-Collapsible messages are also called send-to-sync messages.
-Likewise, there is a limit on how many collapse_keys you can have for
-a particular device. GCM allows a maximum of 4 different collapse keys to be used
-by the GCM server per device
-any given time. In other words, the GCM server can simultaneously store 4 different
-send-to-sync messages, each with a different collapse key. If you exceed this number
-GCM will only keep 4 collapse keys, with no guarantees about which ones they will be.
-See Send-to-sync messages for more information.
-delay_while_idle flag. If the device never gets connected again
-(for instance, if it was factory reset), the message will eventually time out and
-be discarded from GCM storage. The default timeout is 4 weeks, unless the
-time_to_live flag is set.NotRegistered error. See
-How Unregistration Works for more information.delay_while_idle flag. If the device never gets connected again (for instance, if it was factory reset), the message will eventually time out and be discarded from GCM storage. The default timeout is 4 weeks, unless the time_to_live flag is set.NotRegistered error. See How Unregistration Works for more information.Throttling
Keeping the Registration State in Sync
-com.google.android.c2dm.intent.REGISTRATION intent with a registration_id extra, it should save the ID for future use, pass it to the 3rd-party server to complete the registration, and keep track of whether the server completed the registration. If the server fails to complete the registration, it should try again or unregister from GCM.
-Canonical IDs
-registration_id field of the response. Make sure to replace
-the registration ID stored in your server with this canonical ID, as eventually
-the ID you're using will stop working.registration_id field of the response. Make sure to replace the registration ID stored in your server with this canonical ID, as eventually the ID you're using will stop working.Automatic Retry Using Exponential Back-Off
-Unregistration
-
-Why you should rarely unregister
-
-com.google.android.c2dm.intent.REGISTRATION intent with the error extra set as SERVICE_NOT_AVAILABLE, it should retry the failed operation (register or unregister).register and GCM is not a fundamental part of the application, the application could simply ignore the error and try to register again the next time it starts. Otherwise, it should retry the previous operation using exponential back-off. In exponential back-off, each time there is a failure, it should wait twice the previous amount of time before trying again. If the register (or unregister) operation was synchronous, it could be retried in a simple loop. However, since it is asynchronous, the best approach is to schedule a pending intent to retry the operation. The following steps describe how to implement this in the MyIntentService example used above:
+
+
-
+private static final String TOKEN =
+ Long.toBinaryString(new Random().nextLong());
+
+ handleRegistration() method so it creates the pending intent when appropriate:...
+if (error != null) {
+ if ("SERVICE_NOT_AVAILABLE".equals(error)) {
+ long backoffTimeMs = // get back-off time from shared preferences
+ long nextAttempt = SystemClock.elapsedRealtime() + backoffTimeMs;
+ Intent retryIntent = new Intent("com.example.gcm.intent.RETRY");
+ retryIntent.putExtra("token", TOKEN);
+ PendingIntent retryPendingIntent =
+ PendingIntent.getBroadcast(context, 0, retryIntent, 0);
+ AlarmManager am = (AlarmManager)
+ context.getSystemService(Context.ALARM_SERVICE);
+ am.set(AlarmManager.ELAPSED_REALTIME, nextAttempt, retryPendingIntent);
+ backoffTimeMs *= 2; // Next retry should wait longer.
+ // update back-off time on shared preferences
+ } else {
+ // Unrecoverable error, log it
+ Log.i(TAG, "Received error: " + error);
+}
+...
+onHandleIntent() method adding an else if case for the retry intent:...
+} else if (action.equals("com.example.gcm.intent.RETRY")) {
+ String token = intent.getStringExtra("token");
+ // make sure intent was generated by this class, not by a malicious app
+ if (TOKEN.equals(token)) {
+ String registrationId = // get from shared properties
+ if (registrationId != null) {
+ // last operation was attempt to unregister; send UNREGISTER intent again
+ } else {
+ // last operation was attempt to register; send REGISTER intent again
+ }
+}
+...
+
+ MyReceiver in your activity:private final MyBroadcastReceiver mRetryReceiver = new MyBroadcastReceiver();
+
-onCreate() method, register the new instance to receive the com.example.gcm.intent.RETRY intent:
+ ...
+IntentFilter filter = new IntentFilter("com.example.gcm.intent.RETRY");
+filter.addCategory(getPackageName());
+registerReceiver(mRetryReceiver, filter);
+...
-
-
+com.google.android.c2dm.permission.SEND permission. The permission com.google.android.c2dm.permission.SEND is a system permission and as such it cannot be granted to a regular application.How unregistration works
+ onDestroy() method, unregister the broadcast receiver:unregisterReceiver(mRetryReceiver);
+How Unregistration Works
+com.google.android.c2dm.intent.UNREGISTER intent, which is useful when the application offers a logoff feature (so it can unregister on logoff and register again on logon). See the Architectural Overview for more discussion of this topic. This is the sequence of events when an application unregisters itself:
+
+com.google.android.c2dm.intent.UNREGISTER intent, passing the package name as an extra.com.google.android.c2dm.intent.REGISTRATION intent with the unregistered extra set.
-false.
+ false.
NotRegistered error, without any further action being required from
-the 3rd-party server (this scenario happens frequently while an application is
-being developed and tested).NotRegistered error, without any further action being required from the 3rd-party server (this scenario happens frequently while an application is being developed and tested).Send-to-Sync vs. Messages with Payload
@@ -253,45 +196,17 @@ being developed and tested).
But despite these similarities, messages can behave very differently depending -on their particular settings. One major distinction between messages is whether -they are collapsed (where each new message replaces the preceding message) or not -collapsed (where each individual message is delivered). Every message sent in GCM -is either a "send-to-sync" (collapsible) message or a "message with -payload" (non-collapsible message). These concepts are described in more -detail in the following sections.
+But despite these similarities, messages can behave very differently depending on their particular settings. One major distinction between messages is whether they are collapsed (where each new message replaces the preceding message) or not collapsed (where each individual message is delivered). Every message sent in GCM is either a "send-to-sync" (collapsible) message or a "message with payload" (non-collapsible message). These concepts are described in more detail in the following sections.
A send-to-sync (collapsible) message is often a "tickle" that tells -a mobile application to sync data from the server. For example, suppose you have -an email application. When a user receives new email on the server, the server -pings the mobile application with a "New mail" message. This tells the -application to sync to the server to pick up the new email. The server might send -this message multiple times as new mail continues to accumulate, before the application -has had a chance to sync. But if the user has received 25 new emails, there's no -need to preserve every "New mail" message. One is sufficient. Another -example would be a sports application that updates users with the latest score. -Only the most recent message is relevant, so it makes sense to have each new -message replace the preceding message.
- -The email and sports applications are cases where you would probably use the
-GCM collapse_key parameter. A collapse key is an arbitrary
-string that is used to collapse a group of like messages when the device is offline,
-so that only the most recent message gets sent to the client. For example,
-"New mail," "Updates available," and so on
GCM allows a maximum of 4 different collapse keys to be used by the GCM server -at any given time. In other words, the GCM server can simultaneously store 4 -different send-to-sync messages per device, each with a different collapse key. -For example, Device A can have A1, A2, A3, and A4. Device B can have B1, B2, B3, -and B4, and so on. If you exceed this number GCM will only keep 4 collapse keys, with no -guarantees about which ones they will be.
+A send-to-sync (collapsible) message is often a "tickle" that tells a mobile application to sync data from the server. For example, suppose you have an email application. When a user receives new email on the server, the server pings the mobile application with a "New mail" message. This tells the application to sync to the server to pick up the new email. The server might send this message multiple times as new mail continues to accumulate, before the application has had a chance to sync. But if the user has received 25 new emails, there's no need to preserve every "New mail" message. One is sufficient. Another example would be a sports application that updates users with the latest score. Only the most recent message is relevant, so it makes sense to have each new message replace the preceding message.
+ +The email and sports applications are cases where you would probably use the GCM collapse_key parameter. A collapse key is an arbitrary string that is used to collapse a group of like messages when the device is offline, so that only the most recent message gets sent to the client. For example, "New mail," "Updates available," and so on
GCM allows a maximum of 4 different collapse keys to be used by the GCM server at any given time. In other words, the GCM server can simultaneously store 4 different send-to-sync messages, each with a different collapse key. If you exceed this number GCM will only keep 4 collapse keys, with no guarantees about which ones they will be.
Unlike a send-to-sync message, every "message with payload" -(non-collapsible message) is delivered. The payload the message contains can be -up to 4kb. For example, here is a JSON-formatted message in an IM application in -which spectators are discussing a sporting event:
+Unlike a send-to-sync message, every "message with payload" (non-collapsible message) is delivered. The payload the message contains can be up to 4kb. For example, here is a JSON-formatted message in an IM application in which spectators are discussing a sporting event:
{
"registration_id" : "APA91bHun4MxP5egoKMwt2KZFBaFUH-1RYqx...",
@@ -302,42 +217,19 @@ which spectators are discussing a sporting event:
},
}
-A "message with payload" is not simply a "ping" to the
-mobile application to contact the server to fetch data. In the aforementioned IM
-application, for example, you would want to deliver every message, because every
-message has different content. To specify a non-collapsible message, you simply
-omit the collapse_key parameter. Thus GCM will send each message
-individually. Note that the order of delivery is not guaranteed.
GCM will store up to 100 non-collapsible messages. After that, all messages
-are discarded from GCM, and a new message is created that tells the client how
-far behind it is. The message is delivered through a regular
-com.google.android.c2dm.intent.RECEIVE intent, with the following
-extras:
A "message with payload" is not simply a "ping" to the mobile application to contact the server to fetch data. In the aforementioned IM application, for example, you would want to deliver every message, because every message has different content. To specify a non-collapsible message, you simply omit the collapse_key parameter. Thus GCM will send each message individually. Note that the order of delivery is not guaranteed.
GCM will store up to 100 non-collapsible messages. After that, all messages are discarded from GCM, and a new message is created that tells the client how far behind it is. The message is delivered through a regular com.google.android.c2dm.intent.RECEIVE intent, with the following extras:
message_type—The value is always the string
-"deleted_messages".total_deleted—The value is a string with the number of
-deleted messages.message_type—The value is always the string "deleted_messages".total_deleted—The value is a string with the number of deleted messages.The application should respond by syncing with the server to recover the -discarded messages.
+The application should respond by syncing with the server to recover the discarded messages.
If your application does not need to use non-collapsible messages, collapsible -messages are a better choice from a performance standpoint, because they put less -of a burden on the device battery. However, if you use collapsible messages, remember that -GCM only allows a maximum of 4 different collapse keys to be used by the GCM server -per device at any given time. You must not exceed this number, or it could cause -unpredictable consequences.
+If your application does not need to use non-collapsible messages, collapsible messages are a better choice from a performance standpoint, because they put less of a burden on the device battery.
The Time to Live (TTL) feature lets the sender specify the maximum lifespan
-of a message using the time_to_live parameter in the send request.
-The value of this parameter must be a duration from 0 to 2,419,200 seconds, and
-it corresponds to the maximum period of time for which GCM will store and try to
-deliver the message. Requests that don't contain this field default to the maximum
-period of 4 weeks.
The Time to Live (TTL) feature lets the sender specify the maximum lifespan of a message using the time_to_live parameter in the send request. The value of this parameter must be a duration from 0 to 2,419,200 seconds, and it corresponds to the maximum period of time for which GCM will store and try to deliver the message. Requests that don't contain this field default to the maximum period of 4 weeks.
Here are some possible uses for this feature:
GCM will usually deliver messages immediately after they are sent. However,
-this might not always be possible. For example, the device could be turned off,
-offline, or otherwise unavailable. In other cases, the sender itself might request
-that messages not be delivered until the device becomes active by using the
-delay_while_idle flag. Finally, GCM might intentionally delay messages
-to prevent an application from consuming excessive resources and negatively
-impacting battery life.
When this happens, GCM will store the message and deliver it as soon as it's -feasible. While this is fine in most cases, there are some applications for which -a late message might as well never be delivered. For example, if the message is -an incoming call or video chat notification, it will only be meaningful for a -small period of time before the call is terminated. Or if the message is an -invitation to an event, it will be useless if received after the event has ended.
- -Another advantage of specifying the expiration date for a message is that GCM
-will never throttle messages with a time_to_live value of 0 seconds.
-In other words, GCM will guarantee best effort for messages that must be delivered
-"now or never." Keep in mind that a time_to_live value of
-0 means messages that can't be delivered immediately will be discarded. However,
-because such messages are never stored, this provides the best latency for
-sending notifications.
GCM will usually deliver messages immediately after they are sent. However, this might not always be possible. For example, the device could be turned off, offline, or otherwise unavailable. In other cases, the sender itself might request that messages not be delivered until the device becomes active by using the delay_while_idle flag. Finally, GCM might intentionally delay messages to prevent an application from consuming excessive resources and negatively impacting battery life.
When this happens, GCM will store the message and deliver it as soon as it's feasible. While this is fine in most cases, there are some applications for which a late message might as well never be delivered. For example, if the message is an incoming call or video chat notification, it will only be meaningful for a small period of time before the call is terminated. Or if the message is an invitation to an event, it will be useless if received after the event has ended.
+Another advantage of specifying the expiration date for a message is that GCM will never throttle messages with a time_to_live value of 0 seconds. In other words, GCM will guarantee best effort for messages that must be delivered "now or never." Keep in mind that a time_to_live value of 0 means messages that can't be delivered immediately will be discarded. However, because such messages are never stored, this provides the best latency for sending notifications.
Here is an example of a JSON-formatted request that includes TTL:
{
@@ -384,23 +256,9 @@ sending notifications.
Receiving Messages from Multiple Senders
-
-GCM allows multiple parties to send messages to the same application. For
-example, suppose your application is an articles aggregator with multiple
-contributors, and you want each of them to be able to send a message when they
-publish a new article. This message might contain a URL so that the application
-can download the article. Instead of having to centralize all sending activity in
-one location, GCM gives you the ability to let each of these contributors send
-its own messages.
-
-To make this possible, all you need to do is have each sender generate its own
-project number. Then include those IDs in the sender field, separated by commas,
-when requesting a registration. Finally, share the registration ID with your
-partners, and they'll be able to send messages to your application using their
-own authentication keys.
-This code snippet illustrates this feature. Senders are passed as an intent
-extra in a comma-separated list:
-
+GCM allows multiple parties to send messages to the same application. For example, suppose your application is an articles aggregator with multiple contributors, and you want each of them to be able to send a message when they publish a new article. This message might contain a URL so that the application can download the article. Instead of having to centralize all sending activity in one location, GCM gives you the ability to let each of these contributors send its own messages.
+To make this possible, all you need to do is have each sender generate its own project number. Then include those IDs in the sender field, separated by commas, when requesting a registration. Finally, share the registration ID with your partners, and they'll be able to send messages to your application using their own authentication keys.
+This code snippet illustrates this feature. Senders are passed as an intent extra in a comma-separated list:
Intent intent = new Intent(GCMConstants.INTENT_TO_GCM_REGISTRATION);
intent.setPackage(GSF_PACKAGE);
intent.putExtra(GCMConstants.EXTRA_APPLICATION_PENDING_INTENT,
@@ -411,3 +269,4 @@ ontext.startService(intent);
Note that there is limit of 100 multiple senders.
+
diff --git a/docs/html/google/gcm/ccs.jd b/docs/html/google/gcm/ccs.jd
index 244278eba72d..0cadbd245c16 100644
--- a/docs/html/google/gcm/ccs.jd
+++ b/docs/html/google/gcm/ccs.jd
@@ -1,96 +1,93 @@
-page.title=GCM Cloud Connection Server (XMPP)
+page.title=GCM Cloud Connection Server
@jd:body
+Quickview
+
+
+- Get an introduction to key CCS terms and concepts.
+- Learn how to send and receive both upstream and downstream messages in CCS.
+
+
In this document
+ - CCS vs. GCM HTTP
- How to Use CCS
-
- - Authentication
-
-
- - Message Format
-
-
- - Upstream Messages
- - Flow Control
- - Implementing an XMPP-based App Server
-
+ - Flow Control
See Also
-Note: To try out this feature, sign up using
-this form.
+Note: To try out this feature, sign up using this form.
-The GCM Cloud Connection Server (CCS) is a connection server based on XMPP.
-CCS allows 3rd-party app servers (which you're
-responsible for implementing) to communicate
-with Android devices by establishing a persistent TCP connection with Google
-servers using the XMPP protocol. This communication is asynchronous and bidirectional.
-You can continue to use the HTTP request mechanism to send messages to GCM
-servers, side-by-side with CCS which uses XMPP. Some of the benefits of CCS include:
+The GCM Cloud Connection Server (CCS) allows third party servers to communicate with Android devices by establishing a persistent TCP connection with Google servers using the XMPP protocol. This communication is asynchronous and bidirectional.
+You can continue to use the HTTP request mechanism to send messages to GCM servers, side-by-side with CCS which uses XMPP. Some of the benefits of CCS include:
The upstream messaging (device-to-cloud) feature of CCS is part of the Google -Play services platform. Upstream messaging is available through the - -{@code GoogleCloudMessaging} -APIs. For examples, see -Implementing an XMPP-based App Server.
+The upstream messaging (device-to-cloud) feature of CCS is part of the Google Play services platform. Upstream messaging is available through the {@code GoogleCloudMessaging} APIs. To use upstream messaging and the new streamlined registration process, you must set up the Google Play services SDK.
-Note: See -Implementing GCM Server for a list of all the message -parameters and which connection server(s) supports them.
+Note: For an example of an XMPP server, see GCM Server. + +
CCS messaging differs from GCM HTTP messaging in the following ways:
+This document describes how to use CCS. For general concepts and information on how to use GCM HTTP, see the GCM Architectural Overview.
GCM Cloud Connection Server (CCS) is an XMPP endpoint, running on -{@code http://gcm.googleapis.com} port 5235.
+GCM Cloud Connection Server (CCS) is an XMPP endpoint, running on {@code http://gcm.googleapis.com} port 5235.
-CCS requires a Transport Layer Security (TLS) connection. That means the XMPP -client must initiate a TLS connection. -For example in Java, you would call {@code setSocketFactory(SSLSocketFactory)}.
+CCS requires a Transport Layer Security (TLS) connection. That means the XMPP client must initiate a TLS connection. +For example in smack, you would call {@code setSocketFactory(SSLSocketFactory)}, similar to “old style SSL” XMPP connections and https.
-CCS requires a SASL PLAIN authentication mechanism using -{@code <your_GCM_Sender_Id>@gcm.googleapis.com} (GCM sender ID) and the -API key as the password, where the sender ID and API key are the same as described -in Getting Started.
+CCS requires a SASL PLAIN authentication mechanism using {@code <your_GCM_Sender_Id>@gcm.googleapis.com} (GCM sender ID) and the API key as the password, where the sender ID and API key are the same as described in Getting Started.
You can use most XMPP libraries to interact with CCS.
-The following snippets illustrate how to perform authentication in CCS.
<auth mechanism="PLAIN" xmlns="urn:ietf:params:xml:ns:xmpp-sasl">MTI2MjAwMzQ3OTMzQHByb2plY3RzLmdjbS5hb +mRyb2lkLmNvbQAxMjYyMDAzNDc5FzNAcHJvamVjdHMtZ2EtLmFuZHJvaWQuY29tAEFJe mFTeUIzcmNaTmtmbnFLZEZiOW1oekNCaVlwT1JEQTJKV1d0dw==</auth>-
<success xmlns="urn:ietf:params:xml:ns:xmpp-sasl"/>-
CCS uses normal XMPP <message> stanzas. The body of the message must be:
@@ -126,42 +123,25 @@ mFTeUIzcmNaTmtmbnFLZEZiOW1oekNCaVlwT1JEQTJKV1d0dw==</auth> </gcm>-
The JSON payload for server-to-device is similar to what the GCM http endpoint -uses, with these exceptions:
+The JSON payload for server-to-device is similar to what the GCM http endpoint uses, with these exceptions:
message_type = ('ack');
+message_type = ('ack' OR 'nack');
For each device message your app server receives from CCS, it needs to send -an ACK message. -It never needs to send a NACK message. If you don't send an ACK for a message, -CCS will just resend it. +
For each message a device sends to the server, you need to send an ACK message. You never need to send a NACK message. If you don't send an ACK for a message, CCS will just resend it.
-CCS also sends an ACK or NACK for each server-to-device message. If you do not -receive either, it means that the TCP connection was closed in the middle of the -operation and your server needs to resend the messages. See -Flow Control for details. +
CCS also sends an ACK or NACK for each server-to-device message. If you do not receive either, it means that the TCP connection was closed in the middle of the operation and your server needs to resend the messages.
-Note: See -Implementing GCM Server for a list of all the message -parameters and which connection server(s) supports them.
+Here is an XMPP stanza containing the JSON message from a 3rd-party app server to CCS: +
Here is an XMPP stanza containing the JSON message from a 3rd-party server to CCS:
<message id=""> @@ -180,15 +160,7 @@ parameters and which connection server(s) supports them. </message>-
A CCS response can have 3 possible forms. The first one is a regular 'ack' -message. But when the response contains an error, there are 2 -different forms the message can take, described below.
- -Here is an XMPP stanza containing the ACK/NACK message from CCS to 3rd-party app server: +
Here is an XMPP stanza containing the ACK/NACK message from CCS to 3rd-party server:
<message id=""> <gcm xmlns="google:mobile:data"> @@ -199,138 +171,24 @@ different forms the message can take, described below. } </gcm> </message> -- -
A NACK error is a regular XMPP message in which the {@code message_type} status -message is "nack". A NACK message contains:
-Below are some examples.
- -Bad registration:
-<message>
- <data:gcm xmlns:data="google:mobile:data">
- {
- "error":"BAD_REGISTRATION", // error code
- "message_id":"msgId1",
- "from":"PA91bHFOtaQGSwupt5l1og",
- "message_type":"nack"
- }
- </data:gcm>
-</message>
-
-Invalid "time to live":
- -<message>
- <data:gcm xmlns:data="google:mobile:data">
- {
- "error":"InvalidJson : INVALID_TTL : Invalid value (-1) for \"time_to_live\": must be between 0 and \"2419200\"\n",
- "message_id":"msgId1",
- "from":"APA91bHFOtaQGSwupt5l1og",
- "message_type":"nack"
- }
- </data:gcm>
-</message>
-JSON type error:
- -<message>
- <data:gcm xmlns:data="google:mobile:data">
+<message id="">
+ <gcm xmlns="google:mobile:data">
{
- "error":"InvalidJson : JSON_TYPE_ERROR : Field \"delay_while_idle\" must be a JSON java.lang.Boolean: not-boolean-user-supplied-value\n",
- "message_id":"msgId1",
- "from":"APA91bHFOtaQGSwupt5l1og",
- "message_type":"nack"
+ "from":"REGID",
+ "message_id":"m-1366082849205"
+ "error": ERROR_CODE,
+ "message_type":"nack"
}
- </data:gcm>
-</message>
-
-
-The following table lists some of the more common NACK error codes.
- -- Table 1. NACK error codes.
- -| Error Code | -Description | -
|---|---|
| {@code BAD_REGISTRATION} | -The device has a registration ID, but it's invalid. | -
| {@code DEVICE_UNREGISTERED} | -The device is not registered. | -
| {@code INTERNAL_SERVER_ERROR} | -The server encountered an error while trying to process the request. | -
| {@code SERVICE_UNAVAILABLE} | -The CCS connection server is temporarily unavailable, try again later -(using exponential backoff, etc.). | -
| {@code BAD_ACK} | -The ACK message is improperly formed. | -
| {@code AUTHENTICATION_FAILED} | -This is a 401 error indicating that there was an error authenticating the sender account. | -
| {@code INVALID_TTL} | -There was an error in the supplied "time to live" value. | -
| {@code JSON_TYPE_ERROR} | -There was an error in the supplied JSON data type. | -
You can also get a stanza error in certain cases. -A stanza error contains:
-For example:
- -<message id="3" type="error" to="123456789@gcm.googleapis.com/ABC">
- <gcm xmlns="google:mobile:data">
- {"random": "text"}
</gcm>
- <error code="400" type="modify">
- <bad-request xmlns="urn:ietf:params:xml:ns:xmpp-stanzas"/>
- <text xmlns="urn:ietf:params:xml:ns:xmpp-stanzas">
- InvalidJson: JSON_PARSING_ERROR : Missing Required Field: message_id\n
- </text>
- </error>
</message>
+Using CCS and the GoogleCloudMessaging API, you can send messages from a user's device to the cloud.
-Using CCS and the - -{@code GoogleCloudMessaging} -API, you can send messages from a user's device to the cloud.
- -Here is how you send an upstream message using the - -{@code GoogleCloudMessaging} -API. For a complete example, see Implementing GCM Client:
+Here is how you send an upstream message using the GoogleCloudMessaging API. For a complete example, see Getting Started:
GoogleCloudMessaging gcm = GoogleCloudMessaging.get(context);
String GCM_SENDER_ID = "Your-Sender-ID";
@@ -340,15 +198,12 @@ Bundle data = new Bundle();
// Bundle data consists of a key-value pair
data.putString("hello", "world");
// "time to live" parameter
-// This is optional. It specifies a value in seconds up to 4 weeks.
int ttl = [0 seconds, 4 weeks]
gcm.send(GCM_SENDER_ID + "@gcm.googleapis.com", id, ttl, data);
-This call generates the necessary XMPP stanza for sending the upstream message. -The message goes from the app on the device to CCS to the 3rd-party app server. -The stanza has the following format:
+This call generates the necessary XMPP stanza for sending the upstream message. The message goes from the app on the device to CCS to the 3rd-party server. The stanza has the following format:
<message id=""> <gcm xmlns="google:mobile:data"> @@ -364,8 +219,7 @@ The stanza has the following format: </gcm> </message>-
Here is the format of the ACK expected by CCS from 3rd-party app servers in -response to the above message:
+Here is the format of the ACK expected by CCS from 3rd-party servers in response to the above message:
<message id=""> <gcm xmlns="google:mobile:data"> @@ -377,478 +231,13 @@ response to the above message: </gcm> </message>-
Every message sent to CCS receives either an ACK or a NACK response. Messages -that haven't received one of these responses are considered pending. If the pending -message count reaches 1000, the 3rd-party app server should stop sending new messages -and wait for CCS to acknowledge some of the existing pending messages as illustrated in -figure 1:
+
+Every message sent to CCS receives either an ACK or a NACK response. Messages that haven't received one of these responses are considered pending. If the pending message count reaches 1000, the 3rd-party server should stop sending new messages and wait for CCS to acknowledge some of the existing pending messages.
-- Figure 1. Message/ack flow. -
+Conversely, to avoid overloading the 3rd-party server, CCS will stop sending if there are too many unacknowledged messages. Therefore, the 3rd-party server should "ACK" received messages as soon as possible to maintain a constant flow of incoming messages. The aforementioned pending message limit doesn't apply to these ACKs. Even if the pending message count reaches 1000, the 3rd-party server should continue sending ACKs to avoid blocking delivery of new messages.
-Conversely, to avoid overloading the 3rd-party app server, CCS will stop sending -if there are too many unacknowledged messages. Therefore, the 3rd-party app server -should "ACK" upstream messages, received from the client application via CCS, as soon as possible -to maintain a constant flow of incoming messages. The aforementioned pending message limit doesn't -apply to these ACKs. Even if the pending message count reaches 1000, the 3rd-party app server -should continue sending ACKs for messages received from CCS to avoid blocking delivery of new -upstream messages.
- -ACKs are only valid within the context of one connection. If the connection is -closed before a message can be ACKed, the 3rd-party app server should wait for CCS -to resend the upstream message before ACKing it again. Similarly, all pending messages for which an -ACK/NACK was not received from CCS before the connection was closed should be sent again. +
ACKs are only valid within the context of one connection. If the connection is closed before a message can be ACKed, the 3rd-party server should wait for CCS to resend the message before ACKing it again.
-This section gives examples of implementing an app server that works with CCS. -Note that a full GCM implementation requires a client-side implementation, in -addition to the server. For more information, see -Implementing GCM Client. - -
Here is a sample app server written in Java, using the -Smack library.
- -import org.jivesoftware.smack.ConnectionConfiguration;
-import org.jivesoftware.smack.ConnectionConfiguration.SecurityMode;
-import org.jivesoftware.smack.ConnectionListener;
-import org.jivesoftware.smack.PacketInterceptor;
-import org.jivesoftware.smack.PacketListener;
-import org.jivesoftware.smack.XMPPConnection;
-import org.jivesoftware.smack.XMPPException;
-import org.jivesoftware.smack.filter.PacketTypeFilter;
-import org.jivesoftware.smack.packet.DefaultPacketExtension;
-import org.jivesoftware.smack.packet.Message;
-import org.jivesoftware.smack.packet.Packet;
-import org.jivesoftware.smack.packet.PacketExtension;
-import org.jivesoftware.smack.provider.PacketExtensionProvider;
-import org.jivesoftware.smack.provider.ProviderManager;
-import org.jivesoftware.smack.util.StringUtils;
-import org.json.simple.JSONValue;
-import org.json.simple.parser.ParseException;
-import org.xmlpull.v1.XmlPullParser;
-
-import java.util.HashMap;
-import java.util.Map;
-import java.util.Random;
-import java.util.logging.Level;
-import java.util.logging.Logger;
-
-import javax.net.ssl.SSLSocketFactory;
-/**
- * Sample Smack implementation of a client for GCM Cloud Connection Server.
- *
- * <p>For illustration purposes only.
- */
-public class SmackCcsClient {
-
- Logger logger = Logger.getLogger("SmackCcsClient");
-
- public static final String GCM_SERVER = "gcm.googleapis.com";
- public static final int GCM_PORT = 5235;
-
- public static final String GCM_ELEMENT_NAME = "gcm";
- public static final String GCM_NAMESPACE = "google:mobile:data";
-
- static Random random = new Random();
- XMPPConnection connection;
- ConnectionConfiguration config;
-
- /**
- * XMPP Packet Extension for GCM Cloud Connection Server.
- */
- class GcmPacketExtension extends DefaultPacketExtension {
- String json;
-
- public GcmPacketExtension(String json) {
- super(GCM_ELEMENT_NAME, GCM_NAMESPACE);
- this.json = json;
- }
-
- public String getJson() {
- return json;
- }
-
- @Override
- public String toXML() {
- return String.format("<%s xmlns=\"%s\">%s</%s>", GCM_ELEMENT_NAME,
- GCM_NAMESPACE, json, GCM_ELEMENT_NAME);
- }
-
- @SuppressWarnings("unused")
- public Packet toPacket() {
- return new Message() {
- // Must override toXML() because it includes a <body>
- @Override
- public String toXML() {
-
- StringBuilder buf = new StringBuilder();
- buf.append("<message");
- if (getXmlns() != null) {
- buf.append(" xmlns=\"").append(getXmlns()).append("\"");
- }
- if (getLanguage() != null) {
- buf.append(" xml:lang=\"").append(getLanguage()).append("\"");
- }
- if (getPacketID() != null) {
- buf.append(" id=\"").append(getPacketID()).append("\"");
- }
- if (getTo() != null) {
- buf.append(" to=\"").append(StringUtils.escapeForXML(getTo())).append("\"");
- }
- if (getFrom() != null) {
- buf.append(" from=\"").append(StringUtils.escapeForXML(getFrom())).append("\"");
- }
- buf.append(">");
- buf.append(GcmPacketExtension.this.toXML());
- buf.append("</message>");
- return buf.toString();
- }
- };
- }
- }
-
- public SmackCcsClient() {
- // Add GcmPacketExtension
- ProviderManager.getInstance().addExtensionProvider(GCM_ELEMENT_NAME,
- GCM_NAMESPACE, new PacketExtensionProvider() {
-
- @Override
- public PacketExtension parseExtension(XmlPullParser parser)
- throws Exception {
- String json = parser.nextText();
- GcmPacketExtension packet = new GcmPacketExtension(json);
- return packet;
- }
- });
- }
-
- /**
- * Returns a random message id to uniquely identify a message.
- *
- * <p>Note:
- * This is generated by a pseudo random number generator for illustration purpose,
- * and is not guaranteed to be unique.
- *
- */
- public String getRandomMessageId() {
- return "m-" + Long.toString(random.nextLong());
- }
-
- /**
- * Sends a downstream GCM message.
- */
- public void send(String jsonRequest) {
- Packet request = new GcmPacketExtension(jsonRequest).toPacket();
- connection.sendPacket(request);
- }
-
- /**
- * Handles an upstream data message from a device application.
- *
- * <p>This sample echo server sends an echo message back to the device.
- * Subclasses should override this method to process an upstream message.
- */
- public void handleIncomingDataMessage(Map<String, Object> jsonObject) {
- String from = jsonObject.get("from").toString();
-
- // PackageName of the application that sent this message.
- String category = jsonObject.get("category").toString();
-
- // Use the packageName as the collapseKey in the echo packet
- String collapseKey = "echo:CollapseKey";
- @SuppressWarnings("unchecked")
- Map<String, String> payload = (Map<String, String>) jsonObject.get("data");
- payload.put("ECHO", "Application: " + category);
-
- // Send an ECHO response back
- String echo = createJsonMessage(from, getRandomMessageId(), payload, collapseKey, null, false);
- send(echo);
- }
-
- /**
- * Handles an ACK.
- *
- * <p>By default, it only logs a {@code INFO} message, but subclasses could override it to
- * properly handle ACKS.
- */
- public void handleAckReceipt(Map<String, Object> jsonObject) {
- String messageId = jsonObject.get("message_id").toString();
- String from = jsonObject.get("from").toString();
- logger.log(Level.INFO, "handleAckReceipt() from: " + from + ", messageId: " + messageId);
- }
-
- /**
- * Handles a NACK.
- *
- * <p>By default, it only logs a {@code INFO} message, but subclasses could override it to
- * properly handle NACKS.
- */
- public void handleNackReceipt(Map<String, Object> jsonObject) {
- String messageId = jsonObject.get("message_id").toString();
- String from = jsonObject.get("from").toString();
- logger.log(Level.INFO, "handleNackReceipt() from: " + from + ", messageId: " + messageId);
- }
-
- /**
- * Creates a JSON encoded GCM message.
- *
- * @param to RegistrationId of the target device (Required).
- * @param messageId Unique messageId for which CCS will send an "ack/nack" (Required).
- * @param payload Message content intended for the application. (Optional).
- * @param collapseKey GCM collapse_key parameter (Optional).
- * @param timeToLive GCM time_to_live parameter (Optional).
- * @param delayWhileIdle GCM delay_while_idle parameter (Optional).
- * @return JSON encoded GCM message.
- */
- public static String createJsonMessage(String to, String messageId, Map<String, String> payload,
- String collapseKey, Long timeToLive, Boolean delayWhileIdle) {
- Map<String, Object> message = new HashMap<String, Object>();
- message.put("to", to);
- if (collapseKey != null) {
- message.put("collapse_key", collapseKey);
- }
- if (timeToLive != null) {
- message.put("time_to_live", timeToLive);
- }
- if (delayWhileIdle != null && delayWhileIdle) {
- message.put("delay_while_idle", true);
- }
- message.put("message_id", messageId);
- message.put("data", payload);
- return JSONValue.toJSONString(message);
- }
-
- /**
- * Creates a JSON encoded ACK message for an upstream message received from an application.
- *
- * @param to RegistrationId of the device who sent the upstream message.
- * @param messageId messageId of the upstream message to be acknowledged to CCS.
- * @return JSON encoded ack.
- */
- public static String createJsonAck(String to, String messageId) {
- Map<String, Object> message = new HashMap<String, Object>();
- message.put("message_type", "ack");
- message.put("to", to);
- message.put("message_id", messageId);
- return JSONValue.toJSONString(message);
- }
-
- /**
- * Connects to GCM Cloud Connection Server using the supplied credentials.
- *
- * @param username GCM_SENDER_ID@gcm.googleapis.com
- * @param password API Key
- * @throws XMPPException
- */
- public void connect(String username, String password) throws XMPPException {
- config = new ConnectionConfiguration(GCM_SERVER, GCM_PORT);
- config.setSecurityMode(SecurityMode.enabled);
- config.setReconnectionAllowed(true);
- config.setRosterLoadedAtLogin(false);
- config.setSendPresence(false);
- config.setSocketFactory(SSLSocketFactory.getDefault());
-
- // NOTE: Set to true to launch a window with information about packets sent and received
- config.setDebuggerEnabled(true);
-
- // -Dsmack.debugEnabled=true
- XMPPConnection.DEBUG_ENABLED = true;
-
- connection = new XMPPConnection(config);
- connection.connect();
-
- connection.addConnectionListener(new ConnectionListener() {
-
- @Override
- public void reconnectionSuccessful() {
- logger.info("Reconnecting..");
- }
-
- @Override
- public void reconnectionFailed(Exception e) {
- logger.log(Level.INFO, "Reconnection failed.. ", e);
- }
-
- @Override
- public void reconnectingIn(int seconds) {
- logger.log(Level.INFO, "Reconnecting in %d secs", seconds);
- }
-
- @Override
- public void connectionClosedOnError(Exception e) {
- logger.log(Level.INFO, "Connection closed on error.");
- }
-
- @Override
- public void connectionClosed() {
- logger.info("Connection closed.");
- }
- });
-
- // Handle incoming packets
- connection.addPacketListener(new PacketListener() {
-
- @Override
- public void processPacket(Packet packet) {
- logger.log(Level.INFO, "Received: " + packet.toXML());
- Message incomingMessage = (Message) packet;
- GcmPacketExtension gcmPacket =
- (GcmPacketExtension) incomingMessage.getExtension(GCM_NAMESPACE);
- String json = gcmPacket.getJson();
- try {
- @SuppressWarnings("unchecked")
- Map<String, Object> jsonObject =
- (Map<String, Object>) JSONValue.parseWithException(json);
-
- // present for "ack"/"nack", null otherwise
- Object messageType = jsonObject.get("message_type");
-
- if (messageType == null) {
- // Normal upstream data message
- handleIncomingDataMessage(jsonObject);
-
- // Send ACK to CCS
- String messageId = jsonObject.get("message_id").toString();
- String from = jsonObject.get("from").toString();
- String ack = createJsonAck(from, messageId);
- send(ack);
- } else if ("ack".equals(messageType.toString())) {
- // Process Ack
- handleAckReceipt(jsonObject);
- } else if ("nack".equals(messageType.toString())) {
- // Process Nack
- handleNackReceipt(jsonObject);
- } else {
- logger.log(Level.WARNING, "Unrecognized message type (%s)",
- messageType.toString());
- }
- } catch (ParseException e) {
- logger.log(Level.SEVERE, "Error parsing JSON " + json, e);
- } catch (Exception e) {
- logger.log(Level.SEVERE, "Couldn't send echo.", e);
- }
- }
- }, new PacketTypeFilter(Message.class));
-
-
- // Log all outgoing packets
- connection.addPacketInterceptor(new PacketInterceptor() {
- @Override
- public void interceptPacket(Packet packet) {
- logger.log(Level.INFO, "Sent: {0}", packet.toXML());
- }
- }, new PacketTypeFilter(Message.class));
-
- connection.login(username, password);
- }
-
- public static void main(String [] args) {
- final String userName = "Your GCM Sender Id" + "@gcm.googleapis.com";
- final String password = "API Key";
-
- SmackCcsClient ccsClient = new SmackCcsClient();
-
- try {
- ccsClient.connect(userName, password);
- } catch (XMPPException e) {
- e.printStackTrace();
- }
-
- // Send a sample hello downstream message to a device.
- String toRegId = "RegistrationIdOfTheTargetDevice";
- String messageId = ccsClient.getRandomMessageId();
- Map<String, String> payload = new HashMap<String, String>();
- payload.put("Hello", "World");
- payload.put("CCS", "Dummy Message");
- payload.put("EmbeddedMessageId", messageId);
- String collapseKey = "sample";
- Long timeToLive = 10000L;
- Boolean delayWhileIdle = true;
- ccsClient.send(createJsonMessage(toRegId, messageId, payload, collapseKey,
- timeToLive, delayWhileIdle));
- }
-}
-Here is an example of a CCS app server written in Python. This sample echo -server sends an initial message, and for every upstream message received, it sends -a dummy response back to the application that sent the upstream message. This -example illustrates how to connect, send, and receive GCM messages using XMPP. It -shouldn't be used as-is on a production deployment.
- -
-#!/usr/bin/python
-import sys, json, xmpp, random, string
-
-SERVER = 'gcm.googleapis.com'
-PORT = 5235
-USERNAME = "Your GCM Sender Id"
-PASSWORD = "API Key"
-REGISTRATION_ID = "Registration Id of the target device"
-
-unacked_messages_quota = 1000
-send_queue = []
-
-# Return a random alphanumerical id
-def random_id():
- rid = ''
- for x in range(8): rid += random.choice(string.ascii_letters + string.digits)
- return rid
-
-def message_callback(session, message):
- global unacked_messages_quota
- gcm = message.getTags('gcm')
- if gcm:
- gcm_json = gcm[0].getData()
- msg = json.loads(gcm_json)
- if not msg.has_key('message_type'):
- # Acknowledge the incoming message immediately.
- send({'to': msg['from'],
- 'message_type': 'ack',
- 'message_id': msg['message_id']})
- # Queue a response back to the server.
- if msg.has_key('from'):
- # Send a dummy echo response back to the app that sent the upstream message.
- send_queue.append({'to': msg['from'],
- 'message_id': random_id(),
- 'data': {'pong': 1}})
- elif msg['message_type'] == 'ack' or msg['message_type'] == 'nack':
- unacked_messages_quota += 1
-
-def send(json_dict):
- template = ("<message><gcm xmlns='google:mobile:data'>{1}</gcm></message>")
- client.send(xmpp.protocol.Message(
- node=template.format(client.Bind.bound[0], json.dumps(json_dict))))
-
-def flush_queued_messages():
- global unacked_messages_quota
- while len(send_queue) and unacked_messages_quota > 0:
- send(send_queue.pop(0))
- unacked_messages_quota -= 1
-
-client = xmpp.Client('gcm.googleapis.com', debug=['socket'])
-client.connect(server=(SERVER,PORT), secure=1, use_srv=False)
-auth = client.auth(USERNAME, PASSWORD)
-if not auth:
- print 'Authentication failed!'
- sys.exit(1)
-
-client.RegisterHandler('message', message_callback)
-
-send_queue.append({'to': REGISTRATION_ID,
- 'message_id': 'reg_id',
- 'data': {'message_destination': 'RegId',
- 'message_id': random_id()}})
-
-while True:
- client.Process(1)
- flush_queued_messages()
diff --git a/docs/html/google/gcm/client.jd b/docs/html/google/gcm/client.jd
index df357a270309..7604932aa383 100644
--- a/docs/html/google/gcm/client.jd
+++ b/docs/html/google/gcm/client.jd
@@ -1,663 +1,24 @@
-page.title=Implementing GCM Client
+page.title=GCM Client
page.tags="cloud","push","messaging"
@jd:body
A GCM client is a GCM-enabled app that runs on an Android device. To write your -client code, we recommend that you use the - -{@code GoogleCloudMessaging} APIs. -The client helper library that was offered in previous versions of GCM still works, -but it has been superseded by the more efficient - -{@code GoogleCloudMessaging} APIs.
- -A full GCM implementation requires both a client implementation and a server -implementation. For more -information about implementing the server side, see -Implementing GCM Server.
- -The following sections walk you through the steps involved in writing a GCM -client-side application. Your client app can be arbitrarily complex, but at bare -minimum, a GCM client app must include code to register (and thereby get a -registration ID), and a broadcast receiver to receive messages sent by GCM. -
- -To write your client application, use the - -{@code GoogleCloudMessaging} API. -To use this API, you must set up your project to use the Google Play services SDK, -as described in Setup Google Play -Services SDK.
- -Caution: When you add the Play Services library to -your project, be sure to add it with resources, as described in - -Setup Google Play Services SDK. The key point is that you must -reference the library—simply adding a {@code .jar} file to -your Eclipse project will not work. You must follow the directions -for referencing a library, or your app won't be able to access -the library's resources, and it won't run properly. -If you're using Android Studio, this is the string to add to the -{@code dependency} section of your application's {@code build.gradle} file:
- -dependencies {
- compile: "com.google.android.gms:play-services:3.1.+"
-}
-
-
-
-Add the following to your application's manifest:
-com.google.android.c2dm.permission.RECEIVE permission so
-the Android application can register and receive messages.android.permission.INTERNET permission so the Android
-application can send the registration ID to the 3rd party server.android.permission.GET_ACCOUNTS permission as GCM requires
-a Google account (necessary only if if the device is running a version lower than
-Android 4.0.4)android.permission.WAKE_LOCK permission so the application
-can keep the processor from sleeping when a message is received. Optional—use
-only if the app wants to keep the device from sleeping.applicationPackage + ".permission.C2D_MESSAGE"
-permission to prevent other Android applications from registering and receiving
-the Android application's messages. The permission name must exactly match this
-pattern—otherwise the Android application will not receive the messages.com.google.android.c2dm.intent.RECEIVE, with
-the category set
-as applicationPackage. The receiver should require the
-com.google.android.c2dm.SEND permission, so that only the GCM
-Framework can send a message to it. If your app uses an {@link android.app.IntentService}
-(not required, but a common pattern), this receiver should be an instance of
-{@link android.support.v4.content.WakefulBroadcastReceiver}.
-A {@link android.support.v4.content.WakefulBroadcastReceiver} takes care of
-creating and managing a
-
-partial wake lock for your app.android:minSdkVersion="8" or higher in the manifest. This
-ensures that the Android application cannot be installed in an environment in which it
-could not run properly. Here are excerpts from a sample manifest that supports GCM:
- --<manifest package="com.example.gcm" ...> - - <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17"/> - <uses-permission android:name="android.permission.INTERNET" /> - <uses-permission android:name="android.permission.GET_ACCOUNTS" /> - <uses-permission android:name="android.permission.WAKE_LOCK" /> - <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" /> - - <permission android:name="com.example.gcm.permission.C2D_MESSAGE" - android:protectionLevel="signature" /> - <uses-permission android:name="com.example.gcm.permission.C2D_MESSAGE" /> - - <application ...> - <receiver - android:name=".GcmBroadcastReceiver" - android:permission="com.google.android.c2dm.permission.SEND" > - <intent-filter> - <action android:name="com.google.android.c2dm.intent.RECEIVE" /> - <category android:name="com.example.gcm" /> - </intent-filter> - </receiver> - <service android:name=".GcmIntentService" /> - </application> - -</manifest> -- -
Finally, write your application. This section features a sample client -application that illustrates how to use the - -{@code GoogleCloudMessaging} APIs. The sample consists of a main activity -({@code DemoActivity}), a {@link android.support.v4.content.WakefulBroadcastReceiver} -({@code GcmBroadcastReceiver}), and an {@link android.app.IntentService} -({@code GcmIntentService}). You can find the complete source code for this sample at the -open source site.
- -Note the following:
- -As described in -Setup Google Play Services SDK, apps that rely on the Play Services SDK -should always check the device for a compatible Google Play services APK before -accessing Google Play services features. In the sample app this check is done in -two places: in the main activity's {@code onCreate()} method, and in its -{@code onResume()} method. The check in {@code onCreate()} ensures that the app -can't be used without a successful check. The check in {@code onResume()} ensures -that if the user returns to the running app through some other means, such as -through the back button, the check is still performed. If the -device doesn't have a compatible Google Play services APK, your app can call -{@code GooglePlayServicesUtil.getErrorDialog()} to allow users to download the -APK from the Google Play Store or enable it in the device's system settings. -For example:
- -private final static int PLAY_SERVICES_RESOLUTION_REQUEST = 9000;
-...
-@Override
-public void onCreate(Bundle savedInstanceState) {
- super.onCreate(savedInstanceState);
-
- setContentView(R.layout.main);
- mDisplay = (TextView) findViewById(R.id.display);
-
- context = getApplicationContext();
-
- // Check device for Play Services APK.
- if (checkPlayServices()) {
- // If this check succeeds, proceed with normal processing.
- // Otherwise, prompt user to get valid Play Services APK.
- ...
- }
-}
-
-// You need to do the Play Services APK check here too.
-@Override
-protected void onResume() {
- super.onResume();
- checkPlayServices();
-}
-
-/**
- * Check the device to make sure it has the Google Play Services APK. If
- * it doesn't, display a dialog that allows users to download the APK from
- * the Google Play Store or enable it in the device's system settings.
- */
-private boolean checkPlayServices() {
- int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
- if (resultCode != ConnectionResult.SUCCESS) {
- if (GooglePlayServicesUtil.isUserRecoverableError(resultCode)) {
- GooglePlayServicesUtil.getErrorDialog(resultCode, this,
- PLAY_SERVICES_RESOLUTION_REQUEST).show();
- } else {
- Log.i(TAG, "This device is not supported.");
- finish();
- }
- return false;
- }
- return true;
-}
-
-An Android application needs to register with GCM servers before it can receive -messages. When an app registers, it receives a registration ID, which it can then -store for future use. In the following snippet the {@code onCreate()} method in the sample app's -main activity checks to see if the app is already registered with GCM and with -the server:
- -/**
- * Main UI for the demo app.
- */
-public class DemoActivity extends Activity {
-
- public static final String EXTRA_MESSAGE = "message";
- public static final String PROPERTY_REG_ID = "registration_id";
- private static final String PROPERTY_APP_VERSION = "appVersion";
- private final static int PLAY_SERVICES_RESOLUTION_REQUEST = 9000;
-
- /**
- * Substitute you own sender ID here. This is the project number you got
- * from the API Console, as described in "Getting Started."
- */
- String SENDER_ID = "Your-Sender-ID";
-
- /**
- * Tag used on log messages.
- */
- static final String TAG = "GCMDemo";
-
- TextView mDisplay;
- GoogleCloudMessaging gcm;
- AtomicInteger msgId = new AtomicInteger();
- SharedPreferences prefs;
- Context context;
-
- String regid;
-
- @Override
- public void onCreate(Bundle savedInstanceState) {
- super.onCreate(savedInstanceState);
+A GCM client is a GCM-enabled app that runs on an Android device. To write your client code, we recommend that you use the new {@code GoogleCloudMessaging} APIs. The client helper library that was offered in previous versions of GCM still works, but it has been superseded by the more efficient {@code GoogleCloudMessaging} APIs.
- setContentView(R.layout.main);
- mDisplay = (TextView) findViewById(R.id.display);
+A full GCM implementation requires both a client implementation and a server-side implementation. For a step-by-step guide to creating a complete sample implementation that includes both client and server, see Getting Started.
- context = getApplicationContext();
-
- // Check device for Play Services APK. If check succeeds, proceed with
- // GCM registration.
- if (checkPlayServices()) {
- gcm = GoogleCloudMessaging.getInstance(this);
- regid = getRegistrationId(context);
-
- if (regid.isEmpty()) {
- registerInBackground();
- }
- } else {
- Log.i(TAG, "No valid Google Play Services APK found.");
- }
- }
-...
-}
-
-The app calls {@code getRegistrationId()} to see whether there is an existing -registration ID stored in shared preferences:
- -/**
- * Gets the current registration ID for application on GCM service.
- * <p>
- * If result is empty, the app needs to register.
- *
- * @return registration ID, or empty string if there is no existing
- * registration ID.
- */
-private String getRegistrationId(Context context) {
- final SharedPreferences prefs = getGCMPreferences(context);
- String registrationId = prefs.getString(PROPERTY_REG_ID, "");
- if (registrationId.isEmpty()) {
- Log.i(TAG, "Registration not found.");
- return "";
- }
- // Check if app was updated; if so, it must clear the registration ID
- // since the existing regID is not guaranteed to work with the new
- // app version.
- int registeredVersion = prefs.getInt(PROPERTY_APP_VERSION, Integer.MIN_VALUE);
- int currentVersion = getAppVersion(context);
- if (registeredVersion != currentVersion) {
- Log.i(TAG, "App version changed.");
- return "";
- }
- return registrationId;
-}
-...
-/**
- * @return Application's {@code SharedPreferences}.
- */
-private SharedPreferences getGCMPreferences(Context context) {
- // This sample app persists the registration ID in shared preferences, but
- // how you store the regID in your app is up to you.
- return getSharedPreferences(DemoActivity.class.getSimpleName(),
- Context.MODE_PRIVATE);
-}
-
-If the registration ID doesn't exist or the app was updated, -{@code getRegistrationId()} returns an empty string -to indicate that the app needs to get a new regID. {@code getRegistrationId()} calls -the following method to check the app version:
- -/**
- * @return Application's version code from the {@code PackageManager}.
- */
-private static int getAppVersion(Context context) {
- try {
- PackageInfo packageInfo = context.getPackageManager()
- .getPackageInfo(context.getPackageName(), 0);
- return packageInfo.versionCode;
- } catch (NameNotFoundException e) {
- // should never happen
- throw new RuntimeException("Could not get package name: " + e);
- }
-}
-
-
-If there isn't a valid existing registration ID, {@code DemoActivity} calls the -following {@code registerInBackground()} method to register. Note that because the GCM -methods {@code register()} and {@code unregister()} are blocking, this has to -take place on a background thread. This sample uses {@link android.os.AsyncTask} -to accomplish this:
- -
-/**
- * Registers the application with GCM servers asynchronously.
- * <p>
- * Stores the registration ID and app versionCode in the application's
- * shared preferences.
- */
-private void registerInBackground() {
- new AsyncTask() {
- @Override
- protected String doInBackground(Void... params) {
- String msg = "";
- try {
- if (gcm == null) {
- gcm = GoogleCloudMessaging.getInstance(context);
- }
- regid = gcm.register(SENDER_ID);
- msg = "Device registered, registration ID=" + regid;
-
- // You should send the registration ID to your server over HTTP,
- // so it can use GCM/HTTP or CCS to send messages to your app.
- // The request to your server should be authenticated if your app
- // is using accounts.
- sendRegistrationIdToBackend();
-
- // For this demo: we don't need to send it because the device
- // will send upstream messages to a server that echo back the
- // message using the 'from' address in the message.
-
- // Persist the regID - no need to register again.
- storeRegistrationId(context, regid);
- } catch (IOException ex) {
- msg = "Error :" + ex.getMessage();
- // If there is an error, don't just keep trying to register.
- // Require the user to click a button again, or perform
- // exponential back-off.
- }
- return msg;
- }
-
- @Override
- protected void onPostExecute(String msg) {
- mDisplay.append(msg + "\n");
- }
- }.execute(null, null, null);
- ...
- /**
- * Sends the registration ID to your server over HTTP, so it can use GCM/HTTP
- * or CCS to send messages to your app. Not needed for this demo since the
- * device sends upstream messages to a server that echoes back the message
- * using the 'from' address in the message.
- */
- private void sendRegistrationIdToBackend() {
- // Your implementation here.
- }
-}
-
-After registering, the app calls {@code storeRegistrationId()} to store the -registration ID in shared preferences for future use. This is just one way of -persisting a regID. You might choose to use a different approach in your app:
- -/**
- * Stores the registration ID and app versionCode in the application's
- * {@code SharedPreferences}.
- *
- * @param context application's context.
- * @param regId registration ID
- */
-private void storeRegistrationId(Context context, String regId) {
- final SharedPreferences prefs = getGCMPreferences(context);
- int appVersion = getAppVersion(context);
- Log.i(TAG, "Saving regId on app version " + appVersion);
- SharedPreferences.Editor editor = prefs.edit();
- editor.putString(PROPERTY_REG_ID, regId);
- editor.putInt(PROPERTY_APP_VERSION, appVersion);
- editor.commit();
-}
-
-When the user clicks the app's Send button, the app sends an -upstream message using the - -{@code GoogleCloudMessaging} APIs. In order to receive the upstream message, -your server should be connected to CCS. You can use one of the demo servers in -Implementing an XMPP-based App Server to run the sample and connect -to CCS.
- -public void onClick(final View view) {
- if (view == findViewById(R.id.send)) {
- new AsyncTask() {
- @Override
- protected String doInBackground(Void... params) {
- String msg = "";
- try {
- Bundle data = new Bundle();
- data.putString("my_message", "Hello World");
- data.putString("my_action",
- "com.google.android.gcm.demo.app.ECHO_NOW");
- String id = Integer.toString(msgId.incrementAndGet());
- gcm.send(SENDER_ID + "@gcm.googleapis.com", id, data);
- msg = "Sent message";
- } catch (IOException ex) {
- msg = "Error :" + ex.getMessage();
- }
- return msg;
- }
-
- @Override
- protected void onPostExecute(String msg) {
- mDisplay.append(msg + "\n");
- }
- }.execute(null, null, null);
- } else if (view == findViewById(R.id.clear)) {
- mDisplay.setText("");
- }
-}
-
-As described above in Step 2, the app includes a
-{@link android.support.v4.content.WakefulBroadcastReceiver} for the com.google.android.c2dm.intent.RECEIVE
-intent. A broadcast receiver is the mechanism GCM uses to deliver messages. When {@code onClick()}
-calls {@code gcm.send()}, it triggers the broadcast receiver's {@code onReceive()}
-method, which has the responsibility of making sure that the GCM message gets handled.
A {@link android.support.v4.content.WakefulBroadcastReceiver} is a special type of -broadcast receiver that takes care of -creating and managing a - -partial wake lock for your app. -It passes off the work of processing the GCM message to a -{@link android.app.Service} (typically an -{@link android.app.IntentService}), while ensuring that the device does not -go back to sleep in the transition. If you don't hold a wake lock while transitioning -the work to a service, you are effectively allowing the device to go back to sleep before -the work completes. The net result is that the app might not finish processing -the GCM message until some arbitrary point in the future, which is not what you want.
- -Note: Using {@link android.support.v4.content.WakefulBroadcastReceiver} -is not a requirement. If you have a relatively simple app that doesn't require -a service, you can intercept the GCM message in a regular {@link android.content.BroadcastReceiver} -and do your processing there. Once you get the intent that GCM passes into -your broadcast receiver's {@code onReceive()} method, what you do with it -is up to you.
- -This snippet starts {@code GcmIntentService} with the method -{@link android.support.v4.content.WakefulBroadcastReceiver#startWakefulService startWakefulService()}. -This method is comparable to {@link android.content.Context#startService startService()}, except that -the {@link android.support.v4.content.WakefulBroadcastReceiver} is holding a -wake lock when the service starts. The intent that is passed with -{@link android.support.v4.content.WakefulBroadcastReceiver#startWakefulService startWakefulService()} -holds an extra identifying the wake lock:
- - -public class GcmBroadcastReceiver extends WakefulBroadcastReceiver {
- @Override
- public void onReceive(Context context, Intent intent) {
- // Explicitly specify that GcmIntentService will handle the intent.
- ComponentName comp = new ComponentName(context.getPackageName(),
- GcmIntentService.class.getName());
- // Start the service, keeping the device awake while it is launching.
- startWakefulService(context, (intent.setComponent(comp)));
- setResultCode(Activity.RESULT_OK);
- }
-}
-
-The intent service shown below does the actual work of handling the GCM -message. When the service is finished, it calls -{@link android.support.v4.content.WakefulBroadcastReceiver#completeWakefulIntent GcmBroadcastReceiver.completeWakefulIntent()} -to release the wake lock. The -{@link android.support.v4.content.WakefulBroadcastReceiver#completeWakefulIntent completeWakefulIntent()} -method has as its parameter the same intent that was -passed in from the {@link android.support.v4.content.WakefulBroadcastReceiver}. -
- -This snippet processes the GCM message based on message type, and posts the -result in a notification. But what you do with GCM messages in your app is up to -you—the possibilities are endless. For example, the message might be a ping, -telling the app to sync to a server to retrieve new content, or it might be a -chat message that you display in the UI.
- -
-public class GcmIntentService extends IntentService {
- public static final int NOTIFICATION_ID = 1;
- private NotificationManager mNotificationManager;
- NotificationCompat.Builder builder;
-
- public GcmIntentService() {
- super("GcmIntentService");
- }
-
- @Override
- protected void onHandleIntent(Intent intent) {
- Bundle extras = intent.getExtras();
- GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(this);
- // The getMessageType() intent parameter must be the intent you received
- // in your BroadcastReceiver.
- String messageType = gcm.getMessageType(intent);
-
- if (!extras.isEmpty()) { // has effect of unparcelling Bundle
- /*
- * Filter messages based on message type. Since it is likely that GCM
- * will be extended in the future with new message types, just ignore
- * any message types you're not interested in, or that you don't
- * recognize.
- */
- if (GoogleCloudMessaging.
- MESSAGE_TYPE_SEND_ERROR.equals(messageType)) {
- sendNotification("Send error: " + extras.toString());
- } else if (GoogleCloudMessaging.
- MESSAGE_TYPE_DELETED.equals(messageType)) {
- sendNotification("Deleted messages on server: " +
- extras.toString());
- // If it's a regular GCM message, do some work.
- } else if (GoogleCloudMessaging.
- MESSAGE_TYPE_MESSAGE.equals(messageType)) {
- // This loop represents the service doing some work.
- for (int i=0; i<5; i++) {
- Log.i(TAG, "Working... " + (i+1)
- + "/5 @ " + SystemClock.elapsedRealtime());
- try {
- Thread.sleep(5000);
- } catch (InterruptedException e) {
- }
- }
- Log.i(TAG, "Completed work @ " + SystemClock.elapsedRealtime());
- // Post notification of received message.
- sendNotification("Received: " + extras.toString());
- Log.i(TAG, "Received: " + extras.toString());
- }
- }
- // Release the wake lock provided by the WakefulBroadcastReceiver.
- GcmBroadcastReceiver.completeWakefulIntent(intent);
- }
-
- // Put the message into a notification and post it.
- // This is just one simple example of what you might choose to do with
- // a GCM message.
- private void sendNotification(String msg) {
- mNotificationManager = (NotificationManager)
- this.getSystemService(Context.NOTIFICATION_SERVICE);
-
- PendingIntent contentIntent = PendingIntent.getActivity(this, 0,
- new Intent(this, DemoActivity.class), 0);
-
- NotificationCompat.Builder mBuilder =
- new NotificationCompat.Builder(this)
- .setSmallIcon(R.drawable.ic_stat_gcm)
- .setContentTitle("GCM Notification")
- .setStyle(new NotificationCompat.BigTextStyle()
- .bigText(msg))
- .setContentText(msg);
-
- mBuilder.setContentIntent(contentIntent);
- mNotificationManager.notify(NOTIFICATION_ID, mBuilder.build());
- }
-}
-
-To run the sample:
- -To view statistics and any error messages for your GCM applications:
-Developer Console.You will see a page that has a list of all of your apps.
Now you are on the statistics page.
Note: Stats on the Google API Console are not -enabled for GCM. You must use the Developer Console.
+diff --git a/docs/html/google/gcm/gcm.jd b/docs/html/google/gcm/gcm.jd index 3c80b5f9ae5f..ceb82b03702b 100644 --- a/docs/html/google/gcm/gcm.jd +++ b/docs/html/google/gcm/gcm.jd @@ -1,23 +1,48 @@ -page.title=Overview +page.title=GCM Architectural Overview @jd:body
GCM introduces GCM Cloud Connection Server (CCS), which you can use +in tandem with GCM HTTP service/endpoint/APIs. +CCS uses XMPP, and it offers asynchronous, bidirectional +messaging. For more information, see +GCM Cloud Connection Server. +
To jump right into using GCM with your Android - applications, see Getting Started.
+ applications, see the instructions in Getting Started. + + +Here are the primary characteristics of Google Cloud Messaging (GCM):
@@ -41,11 +75,9 @@ Messaging (GCM):This section gives an overview of how GCM works.
This table summarizes the key terms and concepts involved in GCM. It is divided into these categories:
- Table 1. GCM components and credentials.
-| Components | |||
|---|---|---|---|
| Client App | -The GCM-enabled Android application that is running on a - device. This must be a 2.2 Android device that has Google Play Store installed, and it must -have at least one logged in Google account if the device is running a version -lower than Android 4.0.4. Alternatively, for testing you can use an emulator -running Android 2.2 with Google APIs. | +Mobile Device | +The device that is running an Android application that uses +GCM. This must be a 2.2 Android device that has Google Play Store installed, and it must +have at least one logged in Google account if the device is running a version lower than Android 4.0.4. Alternatively, for testing you can use an emulator running Android 2.2 with Google APIs. |
| 3rd-party Application Server | -An application server that you write as part of implementing -GCM. The 3rd-party application server sends data to an -Android application on the device via the GCM connection server. | +An application server that developers set up as part of implementing +GCM in their applications. The 3rd-party application server sends data to an +Android application on the device via the GCM server. | |
| GCM Connection Servers | -The Google-provided servers involved in taking messages from the 3rd-party + | GCM Servers | +The Google servers involved in taking messages from the 3rd-party application server and sending them to the device. |
| Credentials | +Credentials | ||
| Sender ID | -A project number you acquire from the API console, as described in -Getting Started. The sender -ID is used in the registration process to identify a -3rd-party application server that is permitted to send messages to the device. | +A project number you acquire from the API console, as described in Getting Started. The sender +ID is used in the registration process to identify an +Android application that is permitted to send messages to the device. | |
| Application ID | The Android application that is registering to receive messages. The Android application -is identified by the package name from the manifest. +is identified by the package name from the manifest. This ensures that the messages are targeted to the correct Android application. | ||
| Google User Account | -For GCM to work, the mobile device must include at least one Google -account if the device is running a version lower than Android 4.0.4. | +For GCM to work, the mobile device must include at least one Google account if the device is running a version lower than Android 4.0.4. | |
| Sender Auth Token | @@ -146,46 +167,25 @@ server that gives the application server authorized access to Google services. The API key is included in the header of POST requests that send messages.|||
A GCM implementation includes a Google-provided -connection server, a 3rd-party app server that interacts with the connection -server, and a GCM-enabled client app running on an Android device:
- -
+ - Figure 1. GCM Architecture. -
+This is how these components interact:
-These processes are described in more detail below.
-This is the sequence of events that occurs when an Android application +running on a mobile device registers to receive messages:
-The first time the Android application needs to use the messaging service, it
-calls the
-{@code GoogleCloudMessaging} method {@code register()}, as discussed in
-Implementing GCM Client.
-The {@code register()} method returns a registration ID. The Android
-application should store this ID for later use (for instance,
-to check in onCreate() if it is already registered).
+
This registration Intent
+(com.google.android.c2dm.intent.REGISTER) includes the sender ID, and the Android application ID.
Note: Because there is no lifecycle method that is called when the application is run for
+the first time, the registration intent should be sent on onCreate(), but only if the application is not registered yet.
com.google.android.c2dm.intent.REGISTRATION intent which gives the Android application a registration
+ID.
+ The Android application should store this ID for later use (for instance, to check on onCreate() if it is already registered).
+Note that Google may periodically refresh the registration ID, so you should design your Android application
+with the understanding that the com.google.android.c2dm.intent.REGISTRATION intent may be called
+multiple times. Your Android application needs to be able to respond
+accordingly.
The registration ID lasts until the Android application explicitly unregisters +itself, or until Google refreshes the registration ID for your Android application.
+ +Note: When users uninstall an application, it is not automatically unregistered on GCM. It is only unregistered when the GCM server tries to send a message to the device and the device answers that the application is uninstalled or it does not have a broadcast receiver configured to receive com.google.android.c2dm.intent.RECEIVE intents. At that point, your server should mark the device as unregistered (the server will receive a NotRegistered error).
+Note that it might take a few minutes for the registration ID to be completely removed from the GCM server. So if the 3rd-party server sends a message during this time, it will get a valid message ID, even though the message will not be delivered to the device.
+ + + -For an application server to send a message to an Android application, the following things must be in +place:
+ +Here is the sequence of events that occurs when the application server sends a message:
@@ -220,14 +264,13 @@ Android application via Intent broadcast with proper permissions, so that only t targeted Android application gets the message. This wakes the Android application up. The Android application does not need to be running beforehand to receive the message.An Android application can unregister GCM if it no longer wants to receive messages.
-This is the sequence of events that occurs when an Android application installed on a mobile device receives a message:
@@ -239,8 +282,482 @@ pairs from the message payload, if any. in acom.google.android.c2dm.intent.RECEIVE Intent as a set of
extras.
com.google.android.c2dm.intent.RECEIVE Intent
-by key and processes the data.com.google.android.c2dm.intent.RECEIVE Intent by key and processes the data.
+
+
+When mobile device users install Android applications that include GCM, the Google Play Store will inform them that the Android application +includes GCM. They must approve the use of this feature to install the +Android application.
+ + +Before you can write client Android applications that use the GCM feature, you must +have an application server that meets the following criteria:
+ +This section describes how the 3rd-party application server sends messages to one or more mobile devices. Note the following:
+Before the 3rd-party application server can send a message to an + Android application, it must have received a registration ID from it.
+To send a message, the application server issues a POST request to https://android.googleapis.com/gcm/send.
A message request is made of 2 parts: HTTP header and HTTP body.
+ +The HTTP header must contain the following headers:
+Authorization: key=YOUR_API_KEYContent-Type: application/json for JSON; application/x-www-form-urlencoded;charset=UTF-8 for plain text.
+ For example: +
+Content-Type:application/json
+Authorization:key=AIzaSyB-1uEai2WiUapxCs2Q0GZYzPu7Udno5aA
+
+{
+ "registration_ids" : ["APA91bHun4MxP5egoKMwt2KZFBaFUH-1RYqx..."],
+ "data" : {
+ ...
+ },
+}
++
Note: If Content-Type is omitted, the format is assumed to be plain text.
The HTTP body content depends on whether you're using JSON or plain text. For JSON, it must contain a string representing a JSON object with the following fields:
+| Field | +Description | +
|---|---|
registration_ids |
+ A string array with the list of devices (registration IDs) receiving the message. It must contain at least 1 and at most 1000 registration IDs. To send a multicast message, you must use JSON. For sending a single message to a single device, you could use a JSON object with just 1 registration id, or plain text (see below). A request must include a recipient—this can be either a registration ID, an array of registration IDs, or a {@code notification_key}. | +
notification_key |
+ A string that maps a single user to multiple registration IDs associated with that user. This +allows a 3rd-party server to send a single message to multiple app instances (typically on multiple devices) owned by a single user. A 3rd-party server can use {@code notification_key} as the target for a message instead of an individual registration ID (or array of registration IDs). The maximum number of members allowed for a {@code notification_key} is 10. For more discussion of this topic, see User Notifications. Optional. | +
notification_key_name |
+ A name or identifier (can be a username for a 3rd-party app) that is unique to a given user. It is used by 3rd parties to group together registration IDs for a single user. The notification_key_name should be uniquely named per app in case you have multiple apps for the same project ID. This ensures that notifications only go to the intended target app. For more discussion of this topic, see User Notifications. |
+
collapse_key |
+ An arbitrary string (such as "Updates Available") that is used to collapse a group of like messages +when the device is offline, so that only the last message gets sent to the +client. This is intended to avoid sending too many messages to the phone when it +comes back online. Note that since there is no guarantee of the order in which +messages get sent, the "last" message may not actually be the last +message sent by the application server. See Advanced Topics for more discussion of this topic. Optional. | +
data |
+ A JSON object whose fields represents the key-value pairs of the message's payload data. If present, the payload data it will be
+included in the Intent as application data, with the key being the extra's name. For instance, "data":{"score":"3x1"} would result in an intent extra named score whose value is the string 3x1.
+
+There is no limit on the number of key/value pairs, though there is a limit on the total size of the message (4kb). The values could be any JSON object, but we recommend using strings, since the values will be converted to strings in the GCM server anyway. If you want to include objects or other non-string data types (such as integers or booleans), you have to do the conversion to string yourself. Also note that the key cannot be a reserved word (from or any word starting with google.). To complicate things slightly, there are some reserved words (such as collapse_key) that are technically allowed in payload data. However, if the request also contains the word, the value in the request will overwrite the value in the payload data. Hence using words that are defined as field names in this table is not recommended, even in cases where they are technically allowed. Optional. |
+
+
+
delay_while_idle |
+ If included, indicates that the message should not be sent immediately
+if the device is idle. The server will wait for the device to become active, and
+then only the last message for each collapse_key value will be
+sent. Optional. The default value is false, and must be a JSON boolean. |
+
time_to_live |
+ How long (in seconds) the message should be kept on GCM storage if the device is offline. Optional (default time-to-live is 4 weeks, and must be set as a JSON number). | +
restricted_package_name |
+ A string containing the package name of your application. When set, messages will only be sent to registration IDs that match the package name. Optional. + | +
dry_run |
+ If included, allows developers to test their request without actually sending a message. Optional. The default value is false, and must be a JSON boolean.
+ |
+
If you are using plain text instead of JSON, the message fields must be set as HTTP parameters sent in the body, and their syntax is slightly different, as described below: +
| Field | +Description | +
|---|---|
registration_id |
+ Must contain the registration ID of the single device receiving the message. Required. | +
collapse_key |
+ Same as JSON (see previous table). Optional. | +
data.<key> |
+
+ Payload data, expressed as parameters prefixed with data. and suffixed as the key. For instance, a parameter of data.score=3x1 would result in an intent extra named score whose value is the string 3x1. There is no limit on the number of key/value parameters, though there is a limit on the total size of the message. Also note that the key cannot be a reserved word (from or any word starting with
+google.). To complicate things slightly, there are some reserved words (such as collapse_key) that are technically allowed in payload data. However, if the request also contains the word, the value in the request will overwrite the value in the payload data. Hence using words that are defined as field names in this table is not recommended, even in cases where they are technically allowed. Optional. |
+
+
delay_while_idle |
+ Should be represented as 1 or true for true, anything else for false. Optional. The default value is false. |
+
time_to_live |
+ Same as JSON (see previous table). Optional. | +
restricted_package_name |
+ Same as JSON (see previous table). Optional. + | +
dry_run |
+ Same as JSON (see previous table). Optional. + | +
If you want to test your request (either JSON or plain text) without delivering the message to the devices, you can set an optional HTTP or JSON parameter called dry_run with the value true. The result will be almost identical to running the request without this parameter, except that the message will not be delivered to the devices. Consequently, the response will contain fake IDs for the message and multicast fields (see Response format).
Here is the smallest possible request (a message without any parameters and just one recipient) using JSON:
+{ "registration_ids": [ "42" ] }
+
+ And here the same example using plain text:
+registration_id=42+ +
Here is a message with a payload and 6 recipients:
+{ "data": {
+ "score": "5x1",
+ "time": "15:10"
+ },
+ "registration_ids": ["4", "8", "15", "16", "23", "42"]
+}
+ Here is a message with all optional fields set and 6 recipients:
+{ "collapse_key": "score_update",
+ "time_to_live": 108,
+ "delay_while_idle": true,
+ "data": {
+ "score": "4x8",
+ "time": "15:16.2342"
+ },
+ "registration_ids":["4", "8", "15", "16", "23", "42"]
+}
+ And here is the same message using plain-text format (but just 1 recipient):
+ +collapse_key=score_update&time_to_live=108&delay_while_idle=1&data.score=4x8&data.time=15:16.2342®istration_id=42 ++ +
Note: If your organization has a firewall +that restricts the traffic to or +from the Internet, you need to configure it to allow connectivity with GCM in order for +your Android devices to receive messages. +The ports to open are: 5228, 5229, and 5230. GCM typically only uses 5228, but +it sometimes uses 5229 and 5230. GCM doesn't provide specific IPs, so you should allow +your firewall to accept outgoing connections to all IP addresses +contained in the IP blocks listed in Google's ASN of 15169.
+ + +There are two possible outcomes when trying to send a message:
+When the message is processed successfully, the HTTP response has a 200 status and the body contains more information about the status of the message (including possible errors). When the request is rejected, +the HTTP response contains a non-200 status code (such as 400, 401, or 503).
+ +The following table summarizes the statuses that the HTTP response header might contain. Click the troubleshoot link for advice on how to deal with each type of error.
+| Response | +Description | +
|---|---|
| 200 | +Message was processed successfully. The response body will contain more details about the message status, but its format will depend whether the request was JSON or plain text. See Interpreting a success response for more details. | +
| 400 | +Only applies for JSON requests. Indicates that the request could not be parsed as JSON, or it contained invalid fields (for instance, passing a string where a number was expected). The exact failure reason is described in the response and the problem should be addressed before the request can be retried. | +
| 401 | +There was an error authenticating the sender account. Troubleshoot | +
| 5xx | +Errors in the 500-599 range (such as 500 or 503) indicate that there was an internal error in the GCM server while trying to process the request, or that the server is temporarily unavailable (for example, because of timeouts). Sender must retry later, honoring any Retry-After header included in the response. Application servers must implement exponential back-off. Troubleshoot |
+
When a JSON request is successful (HTTP status code 200), the response body contains a JSON object with the following fields:
+| Field | +Description | +
|---|---|
multicast_id |
+ Unique ID (number) identifying the multicast message. | +
success |
+ Number of messages that were processed without an error. | +
failure |
+ Number of messages that could not be processed. | +
canonical_ids |
+ Number of results that contain a canonical registration ID. See Advanced Topics for more discussion of this topic. | +
results |
+ Array of objects representing the status of the messages processed. The objects are listed in the same order as the request (i.e., for each registration ID in the request, its result is listed in the same index in the response) and they can have these fields: +
|
+
If the value of failure and canonical_ids is 0, it's not necessary to parse the remainder of the response. Otherwise, we recommend that you iterate through the results field and do the following for each object in that list:
message_id is set, check for registration_id:
+ registration_id is set, replace the original ID with the new value (canonical ID) in your server database. Note that the original ID is not part of the result, so you need to obtain it from the list of registration_ids passed in the request (using the same index).error:
+ Unavailable, you could retry to send it in another request.NotRegistered, you should remove the registration ID from your server database because the application was uninstalled from the device or it does not have a broadcast receiver configured to receive com.google.android.c2dm.intent.RECEIVE intents.When a plain-text request is successful (HTTP status code 200), the response body contains 1 or 2 lines in the form of key/value pairs.
+The first line is always available and its content is either id=ID of sent message or Error=GCM error code. The second line, if available,
+has the format of registration_id=canonical ID. The second line is optional, and it can only be sent if the first line is not an error. We recommend handling the plain-text response in a similar way as handling the JSON response:
id, check second line:
+ registration_id, gets its value and replace the registration IDs in your server database.Error:
+ NotRegistered, remove the registration ID from your server database.Unavailable as the error code, they would have returned a 500 HTTP status instead).Here are the recommendations for handling the different types of error that might occur when trying to send a message to a device:
+ +registration_id parameter in a plain text message, or in the registration_ids field in JSON).
+MissingRegistration.com.google.android.c2dm.intent.REGISTRATION intent and that you're not truncating it or adding additional characters.
+InvalidRegistration.MismatchSenderId.com.google.android.c2dm.intent.UNREGISTER intent.com.google.android.c2dm.intent.RECEIVE intents.NotRegistered.MessageTooBig.from or any value prefixed by google.) that is used internally by GCM in the com.google.android.c2dm.intent.RECEIVE Intent and cannot be used. Note that some words (such as collapse_key) are also used by GCM but are allowed in the payload, in which case the payload value will be overridden by the GCM value.
+InvalidDataKey.InvalidTtl.
+Authorization header is the correct API key associated with your project. You can check the validity of your API key by running the following command:# api_key=YOUR_API_KEY
+
+# curl --header "Authorization: key=$api_key" --header Content-Type:"application/json" https://android.googleapis.com/gcm/send -d "{\"registration_ids\":[\"ABC\"]}"
+
+
+
+If you receive a 401 HTTP status code, your API key is not valid. Otherwise you should see something like this:
+{"multicast_id":6782339717028231855,"success":0,"failure":1,"canonical_ids":0,"results":[{"error":"InvalidRegistration"}]}
+
+If you want to confirm the validity of a registration ID, you can do so by replacing "ABC" with the registration ID.
+Retry-After header if it's included in the response from the GCM server.error field of a JSON object in the results array is Unavailable.
+error field of a JSON
+object in the results array is InternalServerError.
+InvalidPackageName.
+This section shows a few examples of responses indicating messages that were processed successfully. See Example requests for the requests these responses are based on.
+Here is a simple case of a JSON message successfully sent to one recipient without canonical IDs in the response:
+{ "multicast_id": 108,
+ "success": 1,
+ "failure": 0,
+ "canonical_ids": 0,
+ "results": [
+ { "message_id": "1:08" }
+ ]
+}
+
+Or if the request was in plain-text format:
+id=1:08 ++ +
Here are JSON results for 6 recipients (IDs 4, 8, 15, 16, 23, and 42 respectively) with 3 messages successfully processed, 1 canonical registration ID returned, and 3 errors:
+{ "multicast_id": 216,
+ "success": 3,
+ "failure": 3,
+ "canonical_ids": 1,
+ "results": [
+ { "message_id": "1:0408" },
+ { "error": "Unavailable" },
+ { "error": "InvalidRegistration" },
+ { "message_id": "1:1516" },
+ { "message_id": "1:2342", "registration_id": "32" },
+ { "error": "NotRegistered"}
+ ]
+}
+
+In this example:
+Or if just the 4th message above was sent using plain-text format:
+Error=InvalidRegistration ++
If the 5th message above was also sent using plain-text format:
+id=1:2342 +registration_id=32 ++ +
To view statistics and any error messages for your GCM applications:
+Developer Console.You will see a page that has a list of all of your apps.
Now you are on the statistics page.
Note: Stats on the Google API Console are not enabled for GCM. You must use the Developer Console.
diff --git a/docs/html/google/gcm/gs.jd b/docs/html/google/gcm/gs.jd index f6b7ebe8244b..8ceea0cc8b0d 100644 --- a/docs/html/google/gcm/gs.jd +++ b/docs/html/google/gcm/gs.jd @@ -1,4 +1,4 @@ -page.title=Getting Started +page.title=Getting Started with GCM page.tags="cloud","push","messaging" @jd:body @@ -12,7 +12,8 @@ page.tags="cloud","push","messaging"This document tells you how to get started setting up a GCM +
The sections below guide you through the process of setting up a GCM implementation. -Before you begin, make sure to set up -the Google Play Services SDK. You need this SDK to use the - -{@code GoogleCloudMessaging} methods.
+Before you start, make sure to set up +the Google Play Services SDK. You need this SDK to use the {@code GoogleCloudMessaging} methods. + +Note that a full GCM implementation requires a server-side implementation, in addition to the client implementation in your app. This document offers a complete example that includes both the client and server.

Note: If you already have existing projects, -the first page you see will be the Dashboard page. From there -you can create a new project by opening the project drop-down menu (upper left corner) -and choosing Other projects > Create.
Note: If you already have existing projects, the first page you see will be the Dashboard page. From there you can create a new project by opening the project drop-down menu (upper left corner) and choosing Other projects > Create.
https://code.google.com/apis/console/#project:4815162342-
#project: (4815162342 in this
-example). This is your project number, and it will be used later on as the GCM sender ID.#project: (4815162342 in this example). This is your project number, and it will be used later on as the GCM sender ID.To obtain an API key:
-
-
+
-
+
Take note of the API key value (YourKeyWillBeShownHere)
-in this example, as it will be used later on.
Note: If you need to rotate the key, click -Generate new key. A new key will be created while the old one -will still be active for up to 24 hours. If you want to get rid of the old key -immediately (for example, if you feel it was compromised), click Delete key.
+ Take note of the API key value (YourKeyWillBeShownHere) in this example, as it will be used later on.
Note: If you need to rotate the key, click Generate new key. A new key will be created while the old one will still be active for up to 24 hours. If you want to get rid of the old key immediately (for example, if you feel it was compromised), click Delete key.
-The following sections walk you through the steps of creating client and server-side code.
-Once you've finished the tasks listed above, you're ready to start -implementing GCM. Here is an overview of the basic steps:
+This section walks you through the steps involved in writing a client-side application—that is, the GCM-enabled application that runs on an Android device. This client sample is designed to work in conjunction with the server code shown in Writing the Server Code, below.
+ + + +com.google.android.c2dm.permission.RECEIVE permission so the Android application can register and receive messages.android.permission.INTERNET permission so the Android application can send the registration ID to the 3rd party server.android.permission.GET_ACCOUNTS permission as GCM requires a Google account (necessary only if if the device is running a version lower than Android 4.0.4)android.permission.WAKE_LOCK permission so the application can keep the processor from sleeping when a message is received. Optional—use only if the app wants to keep the device from sleeping.applicationPackage + ".permission.C2D_MESSAGE" permission to prevent other Android applications from registering and receiving the Android application's
+messages. The permission name must exactly match this pattern—otherwise the Android application will not receive the messages.com.google.android.c2dm.intent.RECEIVE, with the category set
+as applicationPackage. The receiver should require the com.google.android.c2dm.SEND permission, so that only the GCM
+Framework can send a message to it. Note that the receiving
+of messages is implemented as an intent.android:minSdkVersion="8" in the manifest. This
+ensures that the Android application cannot be installed in an environment in which it
+could not run properly. Here are excerpts from a manifest that supports GCM:
+ ++<manifest package="com.example.gcm" ...> + + <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17"/> + <uses-permission android:name="android.permission.INTERNET" /> + <uses-permission android:name="android.permission.GET_ACCOUNTS" /> + <uses-permission android:name="android.permission.WAKE_LOCK" /> + <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" /> + + <permission android:name="com.example.gcm.permission.C2D_MESSAGE" + android:protectionLevel="signature" /> + <uses-permission android:name="com.example.gcm.permission.C2D_MESSAGE" /> + + <application ...> + <receiver + android:name=".MyBroadcastReceiver" + android:permission="com.google.android.c2dm.permission.SEND" > + <intent-filter> + <action android:name="com.google.android.c2dm.intent.RECEIVE" /> + <category android:name="com.example.gcm" /> + </intent-filter> + </receiver> + <service android:name=".MyIntentService" /> + </application> + +</manifest> ++ + +
An Android application running on a mobile device registers to receive messages by calling +the {@code GoogleCloudMessaging} method +{@code register(senderID...)}. +This method registers the application for GCM and returns the registration ID. This streamlined approach replaces the previous +GCM registration process. See the example below for details.
+ +Finally, write your application. GCM offers a variety of ways to get the job done:
+ +Here is a sample client application that illustrates how to use the {@code GoogleCloudMessaging} APIs. The sample consists of a main activity ({@code DemoActivity}) and a broadcast receiver ({@code GcmBroadcastReceiver}). You can use this client sample code in conjunction with the server code shown in Writing the Server Code.
+ +Note the following:
+ +An Android application needs to register with GCM servers before it can receive messages. So in its {@code onCreate()} method, {@code DemoActivity} checks to see whether the app is registered with GCM and with the server:
+ +/**
+ * Main UI for the demo app.
+ */
+public class DemoActivity extends Activity {
+
+ public static final String EXTRA_MESSAGE = "message";
+ public static final String PROPERTY_REG_ID = "registration_id";
+ private static final String PROPERTY_APP_VERSION = "appVersion";
+ private static final String PROPERTY_ON_SERVER_EXPIRATION_TIME =
+ "onServerExpirationTimeMs";
+ /**
+ * Default lifespan (7 days) of a reservation until it is considered expired.
+ */
+ public static final long REGISTRATION_EXPIRY_TIME_MS = 1000 * 3600 * 24 * 7;
+
+ /**
+ * Substitute you own sender ID here.
+ */
+ String SENDER_ID = "Your-Sender-ID";
+
+ /**
+ * Tag used on log messages.
+ */
+ static final String TAG = "GCMDemo";
+
+ TextView mDisplay;
+ GoogleCloudMessaging gcm;
+ AtomicInteger msgId = new AtomicInteger();
+ SharedPreferences prefs;
+ Context context;
+
+ String regid;
+
+ @Override
+ public void onCreate(Bundle savedInstanceState) {
+ super.onCreate(savedInstanceState);
+
+ setContentView(R.layout.main);
+ mDisplay = (TextView) findViewById(R.id.display);
+
+ context = getApplicationContext();
+ regid = getRegistrationId(context);
+
+ if (regid.length() == 0) {
+ registerBackground();
+ }
+ gcm = GoogleCloudMessaging.getInstance(this);
+ }
+...
+}
+
+The app calls {@code getRegistrationId()} to see whether there is an existing registration ID stored in shared preferences:
+ +/**
+ * Gets the current registration id for application on GCM service.
+ * <p>
+ * If result is empty, the registration has failed.
+ *
+ * @return registration id, or empty string if the registration is not
+ * complete.
+ */
+private String getRegistrationId(Context context) {
+ final SharedPreferences prefs = getGCMPreferences(context);
+ String registrationId = prefs.getString(PROPERTY_REG_ID, "");
+ if (registrationId.length() == 0) {
+ Log.v(TAG, "Registration not found.");
+ return "";
+ }
+ // check if app was updated; if so, it must clear registration id to
+ // avoid a race condition if GCM sends a message
+ int registeredVersion = prefs.getInt(PROPERTY_APP_VERSION, Integer.MIN_VALUE);
+ int currentVersion = getAppVersion(context);
+ if (registeredVersion != currentVersion || isRegistrationExpired()) {
+ Log.v(TAG, "App version changed or registration expired.");
+ return "";
+ }
+ return registrationId;
+}
+
+...
+
+/**
+ * @return Application's {@code SharedPreferences}.
+ */
+private SharedPreferences getGCMPreferences(Context context) {
+ return getSharedPreferences(DemoActivity.class.getSimpleName(),
+ Context.MODE_PRIVATE);
+}
+
+If the registration ID doesn't exist, or the app was updated, or the registration ID has expired, {@code getRegistrationId()} returns an empty string to indicate that the app needs to get a new regID. {@code getRegistrationId()} calls the following methods to check the app version and whether the regID has expired:
+ +/**
+ * @return Application's version code from the {@code PackageManager}.
+ */
+private static int getAppVersion(Context context) {
+ try {
+ PackageInfo packageInfo = context.getPackageManager()
+ .getPackageInfo(context.getPackageName(), 0);
+ return packageInfo.versionCode;
+ } catch (NameNotFoundException e) {
+ // should never happen
+ throw new RuntimeException("Could not get package name: " + e);
+ }
+}
+
+/**
+ * Checks if the registration has expired.
+ *
+ * <p>To avoid the scenario where the device sends the registration to the
+ * server but the server loses it, the app developer may choose to re-register
+ * after REGISTRATION_EXPIRY_TIME_MS.
+ *
+ * @return true if the registration has expired.
+ */
+private boolean isRegistrationExpired() {
+ final SharedPreferences prefs = getGCMPreferences(context);
+ // checks if the information is not stale
+ long expirationTime =
+ prefs.getLong(PROPERTY_ON_SERVER_EXPIRATION_TIME, -1);
+ return System.currentTimeMillis() > expirationTime;
+}
+
+
+If there isn't a valid existing registration ID, {@code DemoActivity} calls the following {@code registerBackground()} method to register. Note that because GCM methods are blocking, this has to take place on a background thread. This sample uses {@link android.os.AsyncTask} to accomplish this:
+ +
+/**
+ * Registers the application with GCM servers asynchronously.
+ * <p>
+ * Stores the registration id, app versionCode, and expiration time in the
+ * application's shared preferences.
+ */
+private void registerBackground() {
+ new AsyncTask() {
+ @Override
+ protected String doInBackground(Void... params) {
+ String msg = "";
+ try {
+ if (gcm == null) {
+ gcm = GoogleCloudMessaging.getInstance(context);
+ }
+ regid = gcm.register(SENDER_ID);
+ msg = "Device registered, registration id=" + regid;
+
+ // You should send the registration ID to your server over HTTP,
+ // so it can use GCM/HTTP or CCS to send messages to your app.
+
+ // For this demo: we don't need to send it because the device
+ // will send upstream messages to a server that echo back the message
+ // using the 'from' address in the message.
+
+ // Save the regid - no need to register again.
+ setRegistrationId(context, regid);
+ } catch (IOException ex) {
+ msg = "Error :" + ex.getMessage();
+ }
+ return msg;
+ }
+
+ @Override
+ protected void onPostExecute(String msg) {
+ mDisplay.append(msg + "\n");
+ }
+ }.execute(null, null, null);
+}
+
+After registering, the app calls {@code setRegistrationId()} to store the registration ID in shared preferences for future use:
+ +/**
+ * Stores the registration id, app versionCode, and expiration time in the
+ * application's {@code SharedPreferences}.
+ *
+ * @param context application's context.
+ * @param regId registration id
+ */
+private void setRegistrationId(Context context, String regId) {
+ final SharedPreferences prefs = getGCMPreferences(context);
+ int appVersion = getAppVersion(context);
+ Log.v(TAG, "Saving regId on app version " + appVersion);
+ SharedPreferences.Editor editor = prefs.edit();
+ editor.putString(PROPERTY_REG_ID, regId);
+ editor.putInt(PROPERTY_APP_VERSION, appVersion);
+ long expirationTime = System.currentTimeMillis() + REGISTRATION_EXPIRY_TIME_MS;
+
+ Log.v(TAG, "Setting registration expiry time to " +
+ new Timestamp(expirationTime));
+ editor.putLong(PROPERTY_ON_SERVER_EXPIRATION_TIME, expirationTime);
+ editor.commit();
+}
+
+When the user clicks the app's Send button, the app sends an upstream message using the new {@code GoogleCloudMessaging} APIs. In order to receive the upstream message, your server should be connected to CCS. You can use the code shown in Writing the Server Code as a sample XMPP client to connect to CCS.
+ +public void onClick(final View view) {
+ if (view == findViewById(R.id.send)) {
+ new AsyncTask() {
+ @Override
+ protected String doInBackground(Void... params) {
+ String msg = "";
+ try {
+ Bundle data = new Bundle();
+ data.putString("hello", "World");
+ String id = Integer.toString(msgId.incrementAndGet());
+ gcm.send(SENDER_ID + "@gcm.googleapis.com", id, data);
+ msg = "Sent message";
+ } catch (IOException ex) {
+ msg = "Error :" + ex.getMessage();
+ }
+ return msg;
+ }
+
+ @Override
+ protected void onPostExecute(String msg) {
+ mDisplay.append(msg + "\n");
+ }
+ }.execute(null, null, null);
+ } else if (view == findViewById(R.id.clear)) {
+ mDisplay.setText("");
+ }
+}
+
+As described above in Step 1, the app includes a broadcast receiver for the com.google.android.c2dm.intent.RECEIVE intent. This is the mechanism GCM uses to deliver messages. When {@code onClick()} calls {@code gcm.send()}, it triggers the broadcast receiver's {@code onReceive()} method, which has the responsibility of handling the GCM message. In this sample the receiver's {@code onReceive()} method calls {@code sendNotification()} to put the message into a notification:
/**
+ * Handling of GCM messages.
+ */
+public class GcmBroadcastReceiver extends BroadcastReceiver {
+ static final String TAG = "GCMDemo";
+ public static final int NOTIFICATION_ID = 1;
+ private NotificationManager mNotificationManager;
+ NotificationCompat.Builder builder;
+ Context ctx;
+ @Override
+ public void onReceive(Context context, Intent intent) {
+ GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(context);
+ ctx = context;
+ String messageType = gcm.getMessageType(intent);
+ if (GoogleCloudMessaging.MESSAGE_TYPE_SEND_ERROR.equals(messageType)) {
+ sendNotification("Send error: " + intent.getExtras().toString());
+ } else if (GoogleCloudMessaging.MESSAGE_TYPE_DELETED.equals(messageType)) {
+ sendNotification("Deleted messages on server: " +
+ intent.getExtras().toString());
+ } else {
+ sendNotification("Received: " + intent.getExtras().toString());
+ }
+ setResultCode(Activity.RESULT_OK);
+ }
+
+ // Put the GCM message into a notification and post it.
+ private void sendNotification(String msg) {
+ mNotificationManager = (NotificationManager)
+ ctx.getSystemService(Context.NOTIFICATION_SERVICE);
+
+ PendingIntent contentIntent = PendingIntent.getActivity(ctx, 0,
+ new Intent(ctx, DemoActivity.class), 0);
+
+ NotificationCompat.Builder mBuilder =
+ new NotificationCompat.Builder(ctx)
+ .setSmallIcon(R.drawable.ic_stat_gcm)
+ .setContentTitle("GCM Notification")
+ .setStyle(new NotificationCompat.BigTextStyle()
+ .bigText(msg))
+ .setContentText(msg);
+
+ mBuilder.setContentIntent(contentIntent);
+ mNotificationManager.notify(NOTIFICATION_ID, mBuilder.build());
+ }
+}
+
+Here is an example of a CCS server written in Python. You can use this in conjunction with the sample client code shown above. This sample echo server sends an initial message, and for every upstream message received, it sends a dummy response back to the application that sent the upstream message. This example illustrates how to connect, +send, and receive GCM messages using XMPP. It shouldn't be used as-is +on a production deployment. For examples of HTTP-based servers, see GCM Server.
+ +
+#!/usr/bin/python
+import sys, json, xmpp, random, string
+
+SERVER = 'gcm.googleapis.com'
+PORT = 5235
+USERNAME = ''
+PASSWORD = ''
+REGISTRATION_ID = ''
+
+unacked_messages_quota = 1000
+send_queue = []
+
+# Return a random alphanumerical id
+def random_id():
+ rid = ''
+ for x in range(8): rid += random.choice(string.ascii_letters + string.digits)
+ return rid
+
+def message_callback(session, message):
+ global unacked_messages_quota
+ gcm = message.getTags('gcm')
+ if gcm:
+ gcm_json = gcm[0].getData()
+ msg = json.loads(gcm_json)
+ if not msg.has_key('message_type'):
+ # Acknowledge the incoming message immediately.
+ send({'to': msg['from'],
+ 'message_type': 'ack',
+ 'message_id': msg['message_id']})
+ # Queue a response back to the server.
+ if msg.has_key('from'):
+ # Send a dummy echo response back to the app that sent the upstream message.
+ send_queue.append({'to': msg['from'],
+ 'message_id': random_id(),
+ 'data': {'pong': 1}})
+ elif msg['message_type'] == 'ack' or msg['message_type'] == 'nack':
+ unacked_messages_quota += 1
+
+def send(json_dict):
+ template = ("<message><gcm xmlns='google:mobile:data'>{1}</gcm></message>")
+ client.send(xmpp.protocol.Message(
+ node=template.format(client.Bind.bound[0], json.dumps(json_dict))))
+
+def flush_queued_messages():
+ global unacked_messages_quota
+ while len(send_queue) and unacked_messages_quota > 0:
+ send(send_queue.pop(0))
+ unacked_messages_quota -= 1
+
+client = xmpp.Client('gcm.googleapis.com', debug=['socket'])
+client.connect(server=(SERVER,PORT), secure=1, use_srv=False)
+auth = client.auth(USERNAME, PASSWORD)
+if not auth:
+ print 'Authentication failed!'
+ sys.exit(1)
+
+client.RegisterHandler('message', message_callback)
+
+send_queue.append({'to': REGISTRATION_ID,
+ 'message_id': 'reg_id',
+ 'data': {'message_destination': 'RegId',
+ 'message_id': random_id()}})
+
+while True:
+ client.Process(1)
+ flush_queued_messages()
-This document describes the GCM HTTP connection server. Connection servers -are the Google-provided servers that take messages from the 3rd-party -application server and sending them to the device.
- - - -Note: See -Implementing GCM Server for a list of all the message -parameters and which connection server(s) supports them.
- - -To send a message, the application server issues a POST request to
-https://android.googleapis.com/gcm/send.
A message request is made of 2 parts: HTTP header and HTTP body.
- -The HTTP header must contain the following headers:
-Authorization: key=YOUR_API_KEYContent-Type: application/json for JSON; application/x-www-form-urlencoded;charset=UTF-8 for plain text.
- For example: -
-Content-Type:application/json
-Authorization:key=AIzaSyB-1uEai2WiUapxCs2Q0GZYzPu7Udno5aA
-
-{
- "registration_ids" : ["APA91bHun4MxP5egoKMwt2KZFBaFUH-1RYqx..."],
- "data" : {
- ...
- },
-}
--
Note: If Content-Type is omitted, the format
-is assumed to be plain text.
The HTTP body content depends on whether you're using JSON or plain text. -See -Implementing GCM Server for a list of all the -parameters your JSON or plain text message can contain.
- - -Here is the smallest possible request (a message without any parameters and -just one recipient) using JSON:
-{ "registration_ids": [ "42" ] }
-
- And here the same example using plain text:
-registration_id=42- -
Here is a message with a payload and 6 recipients:
-{ "data": {
- "score": "5x1",
- "time": "15:10"
- },
- "registration_ids": ["4", "8", "15", "16", "23", "42"]
-}
- Here is a message with all optional fields set and 6 recipients:
-{ "collapse_key": "score_update",
- "time_to_live": 108,
- "delay_while_idle": true,
- "data": {
- "score": "4x8",
- "time": "15:16.2342"
- },
- "registration_ids":["4", "8", "15", "16", "23", "42"]
-}
- And here is the same message using plain-text format (but just 1 recipient):
- -collapse_key=score_update&time_to_live=108&delay_while_idle=1&data.score=4x8&data.time=15:16.2342®istration_id=42 -- -
Note: If your organization has a firewall -that restricts the traffic to or -from the Internet, you need to configure it to allow connectivity with GCM in order for -your Android devices to receive messages. -The ports to open are: 5228, 5229, and 5230. GCM typically only uses 5228, but -it sometimes uses 5229 and 5230. GCM doesn't provide specific IPs, so you should allow -your firewall to accept outgoing connections to all IP addresses -contained in the IP blocks listed in Google's ASN of 15169.
- - - -There are two possible outcomes when trying to send a message:
-When the message is processed successfully, the HTTP response has a 200 status -and the body contains more information about the status of the message -(including possible errors). When the request is rejected, -the HTTP response contains a non-200 status code (such as 400, 401, or 503).
- -The following table summarizes the statuses that the HTTP response header might -contain. Click the troubleshoot link for advice on how to deal with each type of -error.
-| Response | -Description | -
|---|---|
| 200 | -Message was processed successfully. The response body will contain more -details about the message status, but its format will depend whether the request -was JSON or plain text. See Interpreting a success response -for more details. | -
| 400 | -Only applies for JSON requests. -Indicates that the request could not be parsed as JSON, or it contained invalid -fields (for instance, passing a string where a number was expected). The exact -failure reason is described in the response and the problem should be addressed -before the request can be retried. | -
| 401 | -There was an error authenticating the sender account. -Troubleshoot | -
| 5xx | -Errors in the 500-599 range (such as 500 or 503) indicate that there wa
-an internal error in the GCM server while trying to process the request, or that
-the server is temporarily unavailable (for example, because of timeouts). Sender
-must retry later, honoring any Retry-After header included in the
-response. Application servers must implement exponential back-off.
-Troubleshoot |
-
When a JSON request is successful (HTTP status code 200), the response body -contains a JSON object with the following fields:
-| Field | -Description | -
|---|---|
multicast_id |
- Unique ID (number) identifying the multicast message. | -
success |
- Number of messages that were processed without an error. | -
failure |
- Number of messages that could not be processed. | -
canonical_ids |
- Number of results that contain a canonical registration ID. See -Advanced Topics for more discussion of this topic. | -
results |
- Array of objects representing the status of the messages processed. The
-objects are listed in the same order as the request (i.e., for each registration
-ID in the request, its result is listed in the same index in the response) and
-they can have these fields: -
|
-
If the value of failure and canonical_ids is 0, it's
-not necessary to parse the remainder of the response. Otherwise, we recommend
-that you iterate through the results field and do the following for each object
-in that list:
message_id is set, check for registration_id:
- registration_id is set, replace the original ID with
-the new value (canonical ID) in your server database. Note that the original ID
-is not part of the result, so you need to obtain it from the list of
-code>registration_ids passed in the request (using the same index).error:
- Unavailable, you could retry to send it in another
-request.NotRegistered, you should remove the registration
-ID from your server database because the application was uninstalled from the
-device or it does not have a broadcast receiver configured to receive
-com.google.android.c2dm.intent.RECEIVE intents.When a plain-text request is successful (HTTP status code 200), the response
-body contains 1 or 2 lines in the form of key/value pairs.
-The first line is always available and its content is either id=ID of
-sent message or Error=GCM error code. The second
-line, if available,
-has the format of registration_id=canonical ID. The second
-line is optional, and it can only be sent if the first line is not an error. We
-recommend handling the plain-text response in a similar way as handling the
-JSON response:
id, check second line:
- registration_id, gets its value
-and replace the registration IDs in your server database.Error:
- NotRegistered, remove the registration ID from
-your server database.Unavailable as the
-error code, they would have returned a 500 HTTP status instead).Here are the recommendations for handling the different types of error that -might occur when trying to send a message to a device:
- -registration_id parameter in a plain text message, or in the
-registration_ids field in JSON).
-MissingRegistration.com.google.android.c2dm.intent.REGISTRATION intent and that you're
-not truncating it or adding additional characters.
-InvalidRegistration.MismatchSenderId.com.google.android.c2dm.intent.UNREGISTER
-intent.com.google.android.c2dm.intent.RECEIVE
-intents.NotRegistered.MessageTooBig.from or any value
-prefixed by google.) that is used internally by GCM in the
-com.google.android.c2dm.intent.RECEIVE Intent and cannot be used.
-Note that some words (such as collapse_key) are also used by GCM
-but are allowed in the payload, in which case the payload value will be
-overridden by the GCM value.
-InvalidDataKey.InvalidTtl.
-Authorization header
-is the correct API key associated with your project. You can check the validity
-of your API key by running the following command:# api_key=YOUR_API_KEY
-
-# curl --header "Authorization: key=$api_key" --header Content-Type:"application/json" https://android.googleapis.com/gcm/send -d "{\"registration_ids\":[\"ABC\"]}"
-
-
-
-If you receive a 401 HTTP status code, your API key is not valid. Otherwise you
-should see something like this:
-{"multicast_id":6782339717028231855,"success":0,"failure":1,"canonical_ids":0,"results":[{"error":"InvalidRegistration"}]}
-
-If you want to confirm the validity of a registration ID, you can do so by
-replacing "ABC" with the registration ID.
-Retry-After header if it's included in the response
-from the GCM server.error field of a JSON object in the results array is Unavailable.
-error field of a JSON
-object in the results array is InternalServerError.
-InvalidPackageName.
-This section shows a few examples of responses indicating messages that were -processed successfully. See Request Format for -the requests these responses are based on.
-Here is a simple case of a JSON message successfully sent to one recipient -without canonical IDs in the response:
-{ "multicast_id": 108,
- "success": 1,
- "failure": 0,
- "canonical_ids": 0,
- "results": [
- { "message_id": "1:08" }
- ]
-}
-
-Or if the request was in plain-text format:
-id=1:08 -- -
Here are JSON results for 6 recipients (IDs 4, 8, 15, 16, 23, and 42 respectively) -with 3 messages successfully processed, 1 canonical registration ID returned, -and 3 errors:
-{ "multicast_id": 216,
- "success": 3,
- "failure": 3,
- "canonical_ids": 1,
- "results": [
- { "message_id": "1:0408" },
- { "error": "Unavailable" },
- { "error": "InvalidRegistration" },
- { "message_id": "1:1516" },
- { "message_id": "1:2342", "registration_id": "32" },
- { "error": "NotRegistered"}
- ]
-}
-
-In this example:
-Or if just the 4th message above was sent using plain-text format:
-Error=InvalidRegistration --
If the 5th message above was also sent using plain-text format:
-id=1:2342 -registration_id=32 -- - -
This section gives examples of implementing an app server that works with the -GCM HTTP connection server. Note that a full GCM implementation requires a -client-side implementation, in addition to the server. - - -
Requirements
-For the web server:
-For the Android application:
-Before proceeding with the server and client setup, it's necessary to register -a Google account with the Google API Console, enable Google Cloud Messaging in GCM, -and obtain an API key from the -Google API Console.
-For instructions on how to set up GCM, see Getting Started.
- - -This section describes the different options for setting up an HTTP server.
- -To set up the server using a standard, servlet-compliant web server:
-gcm-server,
-samples/gcm-demo-server, and samples/gcm-demo-appengine.
-
-
- samples/gcm-demo-server/WebContent/WEB-INF/classes/api.key and replace the existing text with the API key obtained above.samples/gcm-demo-server directory.ant war:$ ant war - -Buildfile:build.xml - -init: - [mkdir] Created dir: build/classes - [mkdir] Created dir: dist - -compile: - [javac] Compiling 6 source files to build/classes - -war: - [war] Building war: dist/gcm-demo.war - -BUILD SUCCESSFUL -Total time: 0 seconds -- -
dist/gcm-demo.war to your running server. For instance, if you're using Jetty, copy gcm-demo.war to the webapps directory of the Jetty installation.http://192.168.1.10:8080/gcm-demo/home, where gcm-demo is the application context and /home is the path of the main servlet.
-
- Note: You can get the IP by running ifconfig on Linux or MacOS, or ipconfig on Windows.
You server is now ready.
- -To set up the server using a standard App Engine for Java:
-samples/gcm-demo-appengine/src/com/google/android/gcm/demo/server/ApiKeyInitializer.java
-and replace the existing text with the API key obtained above.
-
- Note: The API key value set in that class will
-be used just once to create a persistent entity on App Engine. If you deploy
-the application, you can use App Engine's Datastore Viewer to change
-it later.
samples/gcm-demo-appengine directory.ant runserver,
-using the -Dsdk.dir to indicate the location of the App Engine SDK
-and -Dserver.host to set your server's hostname or IP address:-$ ant -Dsdk.dir=/opt/google/appengine-java-sdk runserver -Dserver.host=192.168.1.10 -Buildfile: gcm-demo-appengine/build.xml - -init: - [mkdir] Created dir: gcm-demo-appengine/dist - -copyjars: - -compile: - -datanucleusenhance: - [enhance] DataNucleus Enhancer (version 1.1.4) : Enhancement of classes - [enhance] DataNucleus Enhancer completed with success for 0 classes. Timings : input=28 ms, enhance=0 ms, total=28 ms. Consult the log for full details - [enhance] DataNucleus Enhancer completed and no classes were enhanced. Consult the log for full details - -runserver: - [java] Jun 15, 2012 8:46:06 PM com.google.apphosting.utils.jetty.JettyLogger info - [java] INFO: Logging to JettyLogger(null) via com.google.apphosting.utils.jetty.JettyLogger - [java] Jun 15, 2012 8:46:06 PM com.google.apphosting.utils.config.AppEngineWebXmlReader readAppEngineWebXml - [java] INFO: Successfully processed gcm-demo-appengine/WebContent/WEB-INF/appengine-web.xml - [java] Jun 15, 2012 8:46:06 PM com.google.apphosting.utils.config.AbstractConfigXmlReader readConfigXml - [java] INFO: Successfully processed gcm-demo-appengine/WebContent/WEB-INF/web.xml - [java] Jun 15, 2012 8:46:09 PM com.google.android.gcm.demo.server.ApiKeyInitializer contextInitialized - [java] SEVERE: Created fake key. Please go to App Engine admin console, change its value to your API Key (the entity type is 'Settings' and its field to be changed is 'ApiKey'), then restart the server! - [java] Jun 15, 2012 8:46:09 PM com.google.appengine.tools.development.DevAppServerImpl start - [java] INFO: The server is running at http://192.168.1.10:8080/ - [java] Jun 15, 2012 8:46:09 PM com.google.appengine.tools.development.DevAppServerImpl start - [java] INFO: The admin console is running at http://192.168.1.10:8080/_ah/admin -- -
http://192.168.1.10:8080/home, where /home
-is the path of the main servlet.Note: You can get the IP by running ifconfig
-on Linux or MacOS, or ipconfig on Windows.
You server is now ready.
diff --git a/docs/html/google/gcm/notifications.jd b/docs/html/google/gcm/notifications.jd index 4b5a78c059ee..df171cfea52d 100644 --- a/docs/html/google/gcm/notifications.jd +++ b/docs/html/google/gcm/notifications.jd @@ -14,15 +14,14 @@ page.title=User NotificationsNote: To try out this feature, sign up using this form.
+The upstream messaging (device-to-cloud) feature described in this document is part of the Google Play services platform. Upstream messaging is available through the GoogleCloudMessaging APIs. To use upstream messaging and the new streamlined registration process, you must set up the Google Play services SDK.
-With user notifications, 3rd-party app servers can send a single message to -multiple instance of an app running on devices owned by a single user. This feature -is called user notifications. User notifications make it possible for every -app instance that a user owns to reflect the latest messaging state. For example:
+Third party servers can send a single message to multiple instance of an app running on devices owned by a single user. This feature is called user notifications. User notifications make it possible for every app instance that a user owns to reflect the latest messaging state. For example:
-The way this works is that during registration, the 3rd-party server requests -a {@code notification_key}. The {@code notification_key} maps a particular user -to all of the user's associated registration IDs (a regID represents a particular -Android application running on a particular device). Then instead of sending one -message to one regID at a time, the 3rd-party server can send a message to to the -{@code notification_key}, which then sends the message to all of the user's regIDs.
- -Note: A notification dismissal message is like any -other upstream message, meaning that it will be delivered to the other devices that -belong to the specified {@code notification_key}. You should design your app to -handle cases where the app receives a dismissal message, but has not yet displayed -the notification that is being dismissed. You can solve this by caching the dismissal -and then reconciling it with the corresponding notification. +
The way this works is that during registration, the 3rd-party server requests a {@code notification_key}. The {@code notification_key} maps a particular user to all of the user's associated registration IDs (a regID represents a particular Android application running on a particular device). Then instead of sending one message to one regID at a time, the 3rd-party server can send a message to to the {@code notification_key}, which then sends the message to all of the user's regIDs.
+ +Note: A notification dismissal message is like any other upstream message, meaning that it will be delivered to the other devices that belong to the specified {@code notification_key}. You should design your app to handle cases where the app receives a dismissal message, but has not yet displayed the notification that is being dismissed. You can solve this by caching the dismissal and then reconciling it with the corresponding notification.
-You can use this feature with either the XMPP (CCS) or -HTTP connection server.
+You can use this feature with either the new GCM Cloud Connection Server (CCS), or the older GCM HTTP server.
+ +The examples below show you how to perform generate/add/remove operations, -and how to send upstream messages. For generate/add/remove operations, the -message body is JSON.
+The examples in this section show you how to perform generate/add/remove operations, and how to send upstream messages. For generate/add/remove operations, the message body is JSON.
-To send a message, the application server issues a POST request to
-https://android.googleapis.com/gcm/notification.
To send a message, the application server issues a POST request to https://android.googleapis.com/gcm/notification.
Here is the HTTP request header you should use for all create/add/remove operations:
@@ -92,22 +72,12 @@ Header : "project_id": <projectID> Header: "Authorization", "key=API_KEY" -This example shows how to create a new notification_key for a
-notification_key_name called appUser-Chris.
-The {@code notification_key_name} is a name or identifier (can be a username for
-a 3rd-party app) that is unique to a given user. It is used by third parties to
-group together registration IDs for a single user. Note that notification_key_name
-and notification_key are unique to a group of registration IDs. It is also
-important that notification_key_name be uniquely named per app in case
-you have multiple apps for the same project ID. This ensures that notifications
-only go to the intended target app.
This example shows how to create a new notification_key for a notification_key_name called appUser-Chris. The {@code notification_key_name} is a name or identifier (can be a username for a 3rd-party app) that is unique to a given user. It is used by third parties to group together registration IDs for a single user. Note that notification_key_name and notification_key are unique to a group of registration IDs. It is also important that notification_key_name be uniquely named per app in case you have multiple apps for the same project ID. This ensures that notifications only go to the intended target app.
A create operation returns a token (notification_key). Third parties
-must save this token (as well as its mapping to the notification_key_name)
-to use in subsequent operations:
A create operation returns a token (notification_key). Third parties must save this token (as well as its mapping to the notification_key_name) to use in subsequent operations:
request:
{
@@ -116,14 +86,11 @@ to use in subsequent operations:
"registration_ids": ["4", "8", "15", "16", "23", "42"]
}
-This example shows how to add registration IDs for a given notification key. -The maximum number of members allowed for a {@code notification_key} is 10.
+This example shows how to add registration IDs for a given notification key. The maximum number of members allowed for a {@code notification_key} is 10.
-Note that the notification_key_name is not strictly required for
-adding/removing regIDs. But including it protects you against accidentally using
-the incorrect notification_key.
Note that the notification_key_name is not strictly required for adding/removing regIDs. But including it protects you against accidentally using the incorrect notification_key.
request:
{
@@ -133,7 +100,7 @@ the incorrect notification_key.
"registration_ids": ["4", "8", "15", "16", "23", "42"]
}
-This example shows how to remove registration IDs for a given notification key:
request:
@@ -144,14 +111,9 @@ the incorrect notification_key.
"registration_ids": ["4", "8", "15", "16", "23", "42"]
}
-To send an upstream (device-to-cloud) message, you must use the - -{@code GoogleCloudMessaging} API. Specifying a {@code notification_key} as the target -for an upstream message allows a user on one device to send a message to other -devices in the notification group—for example, to dismiss a notification. -Here is an example that shows targeting a {@code notification_key}:
+To send an upstream (device-to-cloud) message, you must use the GoogleCloudMessaging API. Specifying a {@code notification_key} as the target for an upstream message allows a user on one device to send a message to other devices in the notification group—for example, to dismiss a notification. Here is an example that shows targeting a {@code notification_key}:
GoogleCloudMessaging gcm = GoogleCloudMessaging.get(context);
String to = NOTIFICATION_KEY;
@@ -163,21 +125,17 @@ data.putString("hello", "world");
gcm.send(to, id, data);
-This call generates the necessary XMPP stanza for sending the message. The -Bundle data consists of a key-value pair.
+This call generates the necessary XMPP stanza for sending the message. The Bundle data consists of a key-value pair.
-For a complete example, see Implementing GCM Client. +
For a complete example, see Getting Started. -
This section shows examples of the responses that can be returned for -notification key operations.
+This section shows examples of the responses that can be returned for notification key operations.
-When you make a request to create a {@code notification_key} or to add/remove its
-regIDs, a successful response always returns the notification_key.
-his is the {@code notification_key} you will use for sending messages:
When you make a request to create a {@code notification_key} or to add/remove its the wayregIDs, a successful response always returns the notification_key. This is the {@code notification_key} you will use for sending messages:
HTTP status: 200
{
@@ -185,23 +143,18 @@ his is the {@code notification_key} you will use for sending messages:
}
-For a send operation that has a {@code notification_key} as its target, the -possible responses are success, partial success, and failure.
+For a send operation that has a {@code notification_key} as its target, the possible responses are success, partial success, and failure.
-Here is an example of "success"—the {@code notification_key} has 2 regIDs -associated with it, and the message was successfully sent to both of them:
+Here is an example of "success"—the {@code notification_key} has 2 regIDs associated with it, and the message was successfully sent to both of them:
{
"success": 2,
"failure": 0
}
-Here is an example of "partial success"—the {@code notification_key} has -3 regIDs associated with it. The message was successfully send to 1 of the regIDs, -but not to the other 2. The response message lists the regIDs that failed to -receive the message:
+Here is an example of "partial success"—the {@code notification_key} has 3 regIDs associated with it. The message was successfully send to 1 of the regIDs, but not to the other 2. The response message lists the regIDs that failed to receive the message:
{
"success":1,
@@ -212,9 +165,7 @@ receive the message:
]
}
-In the case of failure, the response has HTTP code 503 and no JSON. When a message -fails to be delivered to one or more of the regIDs associated with a {@code notification_key}, -the 3rd-party server should retry.
+In the case of failure, the response has HTTP code 503 and no JSON. When a message fails to be delivered to one or more of the regIDs associated with a {@code notification_key}, the 3rd-party server should retry.
diff --git a/docs/html/google/gcm/server.jd b/docs/html/google/gcm/server.jd index b5e6b480d057..92a1531cdbb4 100644 --- a/docs/html/google/gcm/server.jd +++ b/docs/html/google/gcm/server.jd @@ -1,34 +1,36 @@ -page.title=Implementing GCM Server +page.title=GCM Server @jd:bodyThe server side of GCM consists of 2 components:
-Here are the basic steps you follow to implement your 3rd-party app server:
+This document gives examples of GCM server-side code for HTTP. For an example of an XMPP server (Cloud Connection Server), see Getting Started. Note that a full GCM implementation requires a client-side implementation, in addition to the server. For a complete working example that includes client and server-side code, see Getting Started. + +
For the web server:
For the Android application:
+Before proceeding with the server and client setup, it's necessary to register a Google account with the Google API Console, enable Google Cloud Messaging in GCM, and obtain an API key from the Google API Console.
+For instructions on how to set up GCM, see Getting Started.
-A full GCM implementation requires both a client implementation and a server -implementation. For more -information about implementing the client side, see -Implementing GCM Client.
-This section describes the different options for setting up an HTTP server.
+To set up the server using a standard, servlet-compliant web server:
+gcm-server, samples/gcm-demo-server, and samples/gcm-demo-appengine.
-Currently GCM provides two connection servers: -HTTP and CCS (XMPP). You can use them -separately or in tandem. CCS messaging differs from GCM HTTP messaging in the following ways:
-samples/gcm-demo-server/WebContent/WEB-INF/classes/api.key and replace the existing text with the API key obtained above.samples/gcm-demo-server directory.ant war:$ ant war -Role of the 3rd-party Application Server
+Buildfile:build.xml -Before you can write client Android applications that use the GCM feature, you must -have an application server that meets the following criteria:
+init: + [mkdir] Created dir: build/classes + [mkdir] Created dir: dist -
Here is the general sequence of events that occurs when a 3rd-party application -server sends a message:
-dist/gcm-demo.war to your running server. For instance, if you're using Jetty, copy gcm-demo.war to the webapps directory of the Jetty installation.http://192.168.1.10:8080/gcm-demo/home, where gcm-demo is the application context and /home is the path of the main servlet.
+
+ Note: You can get the IP by running ifconfig on Linux or MacOS, or ipconfig on Windows.
The following sections describe the basic requirements for -sending messages.
+You server is now ready.
-Required. When your app server sends a message in GCM, it must specify a target.
-For HTTP you must specify the target as one of:
-registration_ids: For sending to 1 more more devices (up to 1000).
-When you send a message to multiple registration IDs, that is called a multicast message.notification_key: For sending to multiple devices owned by a single user.For CCS (XMPP):
-Optional. If you are including a payload in the message, you use the data
-parameter to include the payload. This applies for both HTTP and CCS.
The following table lists the parameters that a 3rd-party app server might -include in the JSON messages it sends to a connection server. See the "Where Supported" -column for information about which connection servers support that particular -parameter.
- -- Table 1. Message parameters.
- -| Field | -Description | -Where Supported | -to |
-In CCS, used in place of registration_ids to specify the
-recipient of a message. Its value must be a registration ID.
-The value is a string. Required. |
-CCS | - -
|---|---|---|
message_id |
-In CCS, uniquely identifies a message in an XMPP connection. The value is a -string that uniquely identifies the associated message. The value is a string. Required. | -CCS | -
message_type |
-In CCS, indicates a special status message, typically sent by the system. -However, your app server also uses this parameter to send an 'ack' or 'nack' -message back to the CCS connection server. For more discussion of this topic, see -Cloud Connection Server. The value is a string. Optional. | -CCS | -
registration_ids |
- A string array with the list of devices (registration IDs) receiving the -message. It must contain at least 1 and at most 1000 registration IDs. To send a -multicast message, you must use JSON. For sending a single message to a single -device, you could use a JSON object with just 1 registration id, or plain text -(see below). A request must include a recipient—this can be either a -registration ID, an array of registration IDs, or a {@code notification_key}. -Required. | -HTTP | -
notification_key |
- A string that maps a single user to multiple registration IDs associated -with that user. This allows a 3rd-party server to send a single message to -multiple app instances (typically on multiple devices) owned by a single user. -A 3rd-party server can use {@code notification_key} as the target for a message -instead of an individual registration ID (or array of registration IDs). The maximum -number of members allowed for a {@code notification_key} is 10. For more discussion -of this topic, see User Notifications. Optional. - | -HTTP. This feature is supported in CCS, but you use it by -specifying a notification key in the "to" field. | -
collapse_key |
- An arbitrary string (such as "Updates Available") that is used
-to collapse a group of like messages
-when the device is offline, so that only the last message gets sent to the
-client. This is intended to avoid sending too many messages to the phone when it
-comes back online. Note that since there is no guarantee of the order in which
-messages get sent, the "last" message may not actually be the last
-message sent by the application server. Collapse keys are also called
-send-to-sync messages.
- -Note: GCM allows a maximum of 4 different collapse keys to be -used by the GCM server -at any given time. In other words, the GCM server can simultaneously store 4 -different send-to-sync messages per device, each with a different collapse key. -If you exceed -this number GCM will only keep 4 collapse keys, with no guarantees about which -ones they will be. See Advanced Topics for more -discussion of this topic. Optional. |
-CCS, HTTP | -
data |
- A JSON object whose fields represents the key-value pairs of the message's
-payload data. If present, the payload data it will be
-included in the Intent as application data, with the key being the extra's name.
-For instance, "data":{"score":"3x1"} would result in an intent extra
-named score whose value is the string 3x1.
-There is no limit on the number of key/value pairs, though there is a limit on
-the total size of the message (4kb). The values could be any JSON object, but we
-recommend using strings, since the values will be converted to strings in the GCM
-server anyway. If you want to include objects or other non-string data types
-(such as integers or booleans), you have to do the conversion to string yourself.
-Also note that the key cannot be a reserved word (from or any word
-starting with google.). To complicate things slightly, there are
-some reserved words (such as collapse_key) that are technically
-allowed in payload data. However, if the request also contains the word, the
-value in the request will overwrite the value in the payload data. Hence using
-words that are defined as field names in this table is not recommended, even in
-cases where they are technically allowed. Optional. |
-CCS, HTTP | -
delay_while_idle |
- If included, indicates that the message should not be sent immediately
-if the device is idle. The server will wait for the device to become active, and
-then only the last message for each collapse_key value will be
-sent. The default value is false, and must be a JSON boolean. Optional. |
-CCS, HTTP | -
time_to_live |
- How long (in seconds) the message should be kept on GCM storage if the -device is offline. Optional (default time-to-live is 4 weeks, and must be set as -a JSON number). | -CCS, HTTP | -
restricted_package_name |
- A string containing the package name of your application. When set, messages -will only be sent to registration IDs that match the package name. Optional. - | -HTTP | -
dry_run |
- If included, allows developers to test their request without actually
-sending a message. Optional. The default value is false, and must
-be a JSON boolean.
- |
-HTTP | -
If you want to test your request (either JSON or plain text) without delivering
-the message to the devices, you can set an optional HTTP or JSON parameter called
-dry_run with the value true. The result will be almost
-identical to running the request without this parameter, except that the message
-will not be delivered to the devices. Consequently, the response will contain fake
-IDs for the message and multicast fields.
If you are using plain text instead of JSON, the message fields must be set as -HTTP parameters sent in the body, and their syntax is slightly different, as -described below: -
| Field | -Description | -
|---|---|
registration_id |
- Must contain the registration ID of the single device receiving the message. -Required. | -
collapse_key |
- Same as JSON (see previous table). Optional. | -
data.<key> |
-
- Payload data, expressed as parameters prefixed with data. and
-suffixed as the key. For instance, a parameter of data.score=3x1 would
-result in an intent extra named score whose value is the string
-3x1. There is no limit on the number of key/value parameters, though
-there is a limit on the total size of the message. Also note that the key cannot
-be a reserved word (from or any word starting with
-google.). To complicate things slightly, there are some reserved words
-(such as collapse_key) that are technically allowed in payload data.
-However, if the request also contains the word, the value in the request will
-overwrite the value in the payload data. Hence using words that are defined as
-field names in this table is not recommended, even in cases where they are
-technically allowed. Optional. |
-
-
delay_while_idle |
- Should be represented as 1 or true for
-true, anything else for false. Optional. The default
-value is false. |
-
time_to_live |
- Same as JSON (see previous table). Optional. | -
restricted_package_name |
- Same as JSON (see previous table). Optional. - | -
dry_run |
- Same as JSON (see previous table). Optional. - | -
This is the sequence of events that occurs when an Android application -installed on a mobile device receives a message:
+To set up the server using a standard App Engine for Java:
com.google.android.c2dm.intent.RECEIVE Intent as a set of
-extras.com.google.android.c2dm.intent.RECEIVE Intent
-by key and processes the data.samples/gcm-demo-appengine/src/com/google/android/gcm/demo/server/ApiKeyInitializer.java and replace the existing text with the API key obtained above.
+
+ Note: The API key value set in that class will be used just once to create a persistent entity on App Engine. If you deploy the application, you can use App Engine's Datastore Viewer to change it later.
samples/gcm-demo-appengine directory.ant runserver, using the -Dsdk.dir to indicate the location of the App Engine SDK and -Dserver.host to set your server's hostname or IP address:+$ ant -Dsdk.dir=/opt/google/appengine-java-sdk runserver -Dserver.host=192.168.1.10 +Buildfile: gcm-demo-appengine/build.xml + +init: + [mkdir] Created dir: gcm-demo-appengine/dist + +copyjars: + +compile: + +datanucleusenhance: + [enhance] DataNucleus Enhancer (version 1.1.4) : Enhancement of classes + [enhance] DataNucleus Enhancer completed with success for 0 classes. Timings : input=28 ms, enhance=0 ms, total=28 ms. Consult the log for full details + [enhance] DataNucleus Enhancer completed and no classes were enhanced. Consult the log for full details + +runserver: + [java] Jun 15, 2012 8:46:06 PM com.google.apphosting.utils.jetty.JettyLogger info + [java] INFO: Logging to JettyLogger(null) via com.google.apphosting.utils.jetty.JettyLogger + [java] Jun 15, 2012 8:46:06 PM com.google.apphosting.utils.config.AppEngineWebXmlReader readAppEngineWebXml + [java] INFO: Successfully processed gcm-demo-appengine/WebContent/WEB-INF/appengine-web.xml + [java] Jun 15, 2012 8:46:06 PM com.google.apphosting.utils.config.AbstractConfigXmlReader readConfigXml + [java] INFO: Successfully processed gcm-demo-appengine/WebContent/WEB-INF/web.xml + [java] Jun 15, 2012 8:46:09 PM com.google.android.gcm.demo.server.ApiKeyInitializer contextInitialized + [java] SEVERE: Created fake key. Please go to App Engine admin console, change its value to your API Key (the entity type is 'Settings' and its field to be changed is 'ApiKey'), then restart the server! + [java] Jun 15, 2012 8:46:09 PM com.google.appengine.tools.development.DevAppServerImpl start + [java] INFO: The server is running at http://192.168.1.10:8080/ + [java] Jun 15, 2012 8:46:09 PM com.google.appengine.tools.development.DevAppServerImpl start + [java] INFO: The admin console is running at http://192.168.1.10:8080/_ah/admin ++ +
http://192.168.1.10:8080/home, where /home is the path of the main servlet.Note: You can get the IP by running ifconfig on Linux or MacOS, or ipconfig on Windows.
You server is now ready.
+ -See the documentation for each connection server for more detail on how it -handles responses.
diff --git a/docs/html/google/google_toc.cs b/docs/html/google/google_toc.cs index 7f76c1242ad3..999c44e1734e 100644 --- a/docs/html/google/google_toc.cs +++ b/docs/html/google/google_toc.cs @@ -123,27 +123,24 @@ Google Cloud Messaging