Rollout edit monitor to 10% users

Simplified the logic in whether to enable edit monitor by passing the
rollout percentage directly instead of reading from a env variable as
now we do not rely on any env var to control the rollout precentage.

Test: atest edit_monitor_utils_test
Bug: 365617369
Change-Id: Ia04d5737dafe2c9715a02f84eb5d75ba6119ceb4

3 files changed, 5 insertions, 60 deletions

diff --git a/tools/edit_monitor/daemon_manager.py b/tools/edit_monitor/daemon_manager.py
index 9a0abb6097..2775b58372 100644
--- a/tools/edit_monitor/daemon_manager.py
+++ b/tools/edit_monitor/daemon_manager.py
@@ -84,7 +84,7 @@ class DaemonManager:
         "edit_monitor",
         self.user_name,
         "ENABLE_EDIT_MONITOR",
-        "EDIT_MONITOR_ROLLOUT_PERCENTAGE",
+        10,
     ):
       logging.warning("Edit monitor is disabled, exiting...")
       return
diff --git a/tools/edit_monitor/utils.py b/tools/edit_monitor/utils.py
index 1a3275c6e2..b88949d300 100644
--- a/tools/edit_monitor/utils.py
+++ b/tools/edit_monitor/utils.py
@@ -21,7 +21,7 @@ def is_feature_enabled(
     feature_name: str,
     user_name: str,
     enable_flag: str = None,
-    rollout_flag: str = None,
+    rollout_percent: int = 100,
 ) -> bool:
   """Determine whether the given feature is enabled.
 
@@ -46,26 +46,8 @@ def is_feature_enabled(
       logging.info("feature: %s is enabled", feature_name)
       return True
 
-  if not rollout_flag:
-    return True
-
   hash_object = hashlib.sha256()
   hash_object.update((user_name + feature_name).encode("utf-8"))
   hash_number = int(hash_object.hexdigest(), 16) % 100
 
-  roll_out_percentage = os.environ.get(rollout_flag, "0")
-  try:
-    percentage = int(roll_out_percentage)
-    if percentage < 0 or percentage > 100:
-      logging.warning(
-          "Rollout percentage: %s out of range, disable the feature.",
-          roll_out_percentage,
-      )
-      return False
-    return hash_number < percentage
-  except ValueError:
-    logging.warning(
-        "Invalid rollout percentage: %s, disable the feature.",
-        roll_out_percentage,
-    )
-    return False
+  return hash_number < rollout_percent
diff --git a/tools/edit_monitor/utils_test.py b/tools/edit_monitor/utils_test.py
index 7d7e4b207c..1c30aa1acc 100644
--- a/tools/edit_monitor/utils_test.py
+++ b/tools/edit_monitor/utils_test.py
@@ -46,60 +46,23 @@ class EnableFeatureTest(unittest.TestCase):
         )
     )
 
-  @mock.patch.dict(
-      os.environ, {ROLLOUT_TEST_FEATURE_FLAG: 'invalid'}, clear=True
-  )
-  def test_feature_disabled_with_invalid_rollout_percentage(self):
-    self.assertFalse(
-        utils.is_feature_enabled(
-            TEST_FEATURE,
-            TEST_USER,
-            ENABLE_TEST_FEATURE_FLAG,
-            ROLLOUT_TEST_FEATURE_FLAG,
-        )
-    )
-
-  @mock.patch.dict(os.environ, {ROLLOUT_TEST_FEATURE_FLAG: '101'}, clear=True)
-  def test_feature_disabled_with_rollout_percentage_too_high(self):
-    self.assertFalse(
-        utils.is_feature_enabled(
-            TEST_FEATURE,
-            TEST_USER,
-            ENABLE_TEST_FEATURE_FLAG,
-            ROLLOUT_TEST_FEATURE_FLAG,
-        )
-    )
-
-  @mock.patch.dict(os.environ, {ROLLOUT_TEST_FEATURE_FLAG: '-1'}, clear=True)
-  def test_feature_disabled_with_rollout_percentage_too_low(self):
-    self.assertFalse(
-        utils.is_feature_enabled(
-            TEST_FEATURE,
-            TEST_USER,
-            ENABLE_TEST_FEATURE_FLAG,
-            ROLLOUT_TEST_FEATURE_FLAG,
-        )
-    )
-
-  @mock.patch.dict(os.environ, {ROLLOUT_TEST_FEATURE_FLAG: '90'}, clear=True)
   def test_feature_enabled_with_rollout_percentage(self):
     self.assertTrue(
         utils.is_feature_enabled(
             TEST_FEATURE,
             TEST_USER,
             ENABLE_TEST_FEATURE_FLAG,
-            ROLLOUT_TEST_FEATURE_FLAG,
+            90,
         )
     )
 
-  @mock.patch.dict(os.environ, {ROLLOUT_TEST_FEATURE_FLAG: '10'}, clear=True)
   def test_feature_disabled_with_rollout_percentage(self):
     self.assertFalse(
         utils.is_feature_enabled(
             TEST_FEATURE,
             TEST_USER,
             ENABLE_TEST_FEATURE_FLAG,
-            ROLLOUT_TEST_FEATURE_FLAG,
+            10,
         )
     )