From 8676d8ab2e5667d7c12774effc64b3ab99344a8d Mon Sep 17 00:00:00 2001
From: Will Hunt <will@half-shot.uk>
Date: Tue, 29 Sep 2020 13:11:02 +0100
Subject: [PATCH] Filter out appservices from mau count (#8404)

This is an attempt to fix #8403.
---
 changelog.d/8404.misc                           |  1 +
 .../databases/main/monthly_active_users.py      |  9 ++++++++-
 tests/storage/test_monthly_active_users.py      | 17 ++++++++++++++++-
 3 files changed, 25 insertions(+), 2 deletions(-)
 create mode 100644 changelog.d/8404.misc

diff --git a/changelog.d/8404.misc b/changelog.d/8404.misc
new file mode 100644
index 000000000..7aadded6c
--- /dev/null
+++ b/changelog.d/8404.misc
@@ -0,0 +1 @@
+Do not include appservice users when calculating the total MAU for a server.
diff --git a/synapse/storage/databases/main/monthly_active_users.py b/synapse/storage/databases/main/monthly_active_users.py
index e0cedd1aa..e93aad33c 100644
--- a/synapse/storage/databases/main/monthly_active_users.py
+++ b/synapse/storage/databases/main/monthly_active_users.py
@@ -41,7 +41,14 @@ class MonthlyActiveUsersWorkerStore(SQLBaseStore):
         """
 
         def _count_users(txn):
-            sql = "SELECT COALESCE(count(*), 0) FROM monthly_active_users"
+            # Exclude app service users
+            sql = """
+                SELECT COALESCE(count(*), 0)
+                FROM monthly_active_users
+                    LEFT JOIN users
+                    ON monthly_active_users.user_id=users.name
+                WHERE (users.appservice_id IS NULL OR users.appservice_id = '');
+            """
             txn.execute(sql)
             (count,) = txn.fetchone()
             return count
diff --git a/tests/storage/test_monthly_active_users.py b/tests/storage/test_monthly_active_users.py
index 643072bba..8d97b6d4c 100644
--- a/tests/storage/test_monthly_active_users.py
+++ b/tests/storage/test_monthly_active_users.py
@@ -137,6 +137,21 @@ class MonthlyActiveUsersTestCase(unittest.HomeserverTestCase):
         count = self.get_success(self.store.get_monthly_active_count())
         self.assertEqual(count, 1)
 
+    def test_appservice_user_not_counted_in_mau(self):
+        self.get_success(
+            self.store.register_user(
+                user_id="@appservice_user:server", appservice_id="wibble"
+            )
+        )
+        count = self.get_success(self.store.get_monthly_active_count())
+        self.assertEqual(count, 0)
+
+        d = self.store.upsert_monthly_active_user("@appservice_user:server")
+        self.get_success(d)
+
+        count = self.get_success(self.store.get_monthly_active_count())
+        self.assertEqual(count, 0)
+
     def test_user_last_seen_monthly_active(self):
         user_id1 = "@user1:server"
         user_id2 = "@user2:server"
@@ -383,7 +398,7 @@ class MonthlyActiveUsersTestCase(unittest.HomeserverTestCase):
         self.get_success(self.store.upsert_monthly_active_user(appservice2_user1))
 
         count = self.get_success(self.store.get_monthly_active_count())
-        self.assertEqual(count, 4)
+        self.assertEqual(count, 1)
 
         d = self.store.get_monthly_active_count_by_service()
         result = self.get_success(d)