Hack to add push priority to push notifications (#7765)

* Remove obsolete comment about ancient temporary code

Signed-off-by: Olivier Wilkinson (reivilibre) <olivier@librepush.net>

* Implement hack to set push priority

based on whether the tweaks indicate the event might cause
effects.

* Changelog for 7765

Signed-off-by: Olivier Wilkinson (reivilibre) <olivier@librepush.net>

* Antilint

* Add tests for push priority

Signed-off-by: Olivier Wilkinson (reivilibre) <olivier@librepush.net>

* Update synapse/push/httppusher.py

Co-authored-by: Brendan Abolivier <babolivier@matrix.org>

* Antilint

* Remove needless invites from tests.

Co-authored-by: Brendan Abolivier <babolivier@matrix.org>

3 files changed, 362 insertions, 8 deletions

diff --git a/changelog.d/7765.misc b/changelog.d/7765.misc
new file mode 100644
index 0000000000..fa9cfd24cb
--- /dev/null
+++ b/changelog.d/7765.misc
@@ -0,0 +1 @@
+Send push notifications with a high or low priority depending upon whether they may generate user-observable effects.
diff --git a/synapse/push/httppusher.py b/synapse/push/httppusher.py
index ed60dbc1bf..2fac07593b 100644
--- a/synapse/push/httppusher.py
+++ b/synapse/push/httppusher.py
@@ -20,6 +20,7 @@ from prometheus_client import Counter
 from twisted.internet import defer
 from twisted.internet.error import AlreadyCalled, AlreadyCancelled
 
+from synapse.api.constants import EventTypes
 from synapse.logging import opentracing
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.push import PusherConfigException
@@ -305,12 +306,23 @@ class HttpPusher(object):
 
     @defer.inlineCallbacks
     def _build_notification_dict(self, event, tweaks, badge):
+        priority = "low"
+        if (
+            event.type == EventTypes.Encrypted
+            or tweaks.get("highlight")
+            or tweaks.get("sound")
+        ):
+            # HACK send our push as high priority only if it generates a sound, highlight
+            #  or may do so (i.e. is encrypted so has unknown effects).
+            priority = "high"
+
         if self.data.get("format") == "event_id_only":
             d = {
                 "notification": {
                     "event_id": event.event_id,
                     "room_id": event.room_id,
                     "counts": {"unread": badge},
+                    "prio": priority,
                     "devices": [
                         {
                             "app_id": self.app_id,
@@ -334,9 +346,8 @@ class HttpPusher(object):
                 "room_id": event.room_id,
                 "type": event.type,
                 "sender": event.user_id,
-                "counts": {  # -- we don't mark messages as read yet so
-                    # we have no way of knowing
-                    # Just set the badge to 1 until we have read receipts
+                "prio": priority,
+                "counts": {
                     "unread": badge,
                     # 'missed_calls': 2
                 },
diff --git a/tests/push/test_http.py b/tests/push/test_http.py
index baf9c785f4..b567868b02 100644
--- a/tests/push/test_http.py
+++ b/tests/push/test_http.py
@@ -25,7 +25,6 @@ from tests.unittest import HomeserverTestCase
 
 
 class HTTPPusherTests(HomeserverTestCase):
-
     servlets = [
         synapse.rest.admin.register_servlets_for_client_rest_resource,
         room.register_servlets,
@@ -35,7 +34,6 @@ class HTTPPusherTests(HomeserverTestCase):
     hijack_auth = False
 
     def make_homeserver(self, reactor, clock):
-
         self.push_attempts = []
 
         m = Mock()
@@ -90,9 +88,6 @@ class HTTPPusherTests(HomeserverTestCase):
         # Create a room
         room = self.helper.create_room_as(user_id, tok=access_token)
 
-        # Invite the other person
-        self.helper.invite(room=room, src=user_id, tok=access_token, targ=other_user_id)
-
         # The other user joins
         self.helper.join(room=room, user=other_user_id, tok=other_access_token)
 
@@ -157,3 +152,350 @@ class HTTPPusherTests(HomeserverTestCase):
         pushers = list(pushers)
         self.assertEqual(len(pushers), 1)
         self.assertTrue(pushers[0]["last_stream_ordering"] > last_stream_ordering)
+
+    def test_sends_high_priority_for_encrypted(self):
+        """
+        The HTTP pusher will send pushes at high priority if they correspond
+        to an encrypted message.
+        This will happen both in 1:1 rooms and larger rooms.
+        """
+        # Register the user who gets notified
+        user_id = self.register_user("user", "pass")
+        access_token = self.login("user", "pass")
+
+        # Register the user who sends the message
+        other_user_id = self.register_user("otheruser", "pass")
+        other_access_token = self.login("otheruser", "pass")
+
+        # Register a third user
+        yet_another_user_id = self.register_user("yetanotheruser", "pass")
+        yet_another_access_token = self.login("yetanotheruser", "pass")
+
+        # Create a room
+        room = self.helper.create_room_as(user_id, tok=access_token)
+
+        # The other user joins
+        self.helper.join(room=room, user=other_user_id, tok=other_access_token)
+
+        # Register the pusher
+        user_tuple = self.get_success(
+            self.hs.get_datastore().get_user_by_access_token(access_token)
+        )
+        token_id = user_tuple["token_id"]
+
+        self.get_success(
+            self.hs.get_pusherpool().add_pusher(
+                user_id=user_id,
+                access_token=token_id,
+                kind="http",
+                app_id="m.http",
+                app_display_name="HTTP Push Notifications",
+                device_display_name="pushy push",
+                pushkey="a@example.com",
+                lang=None,
+                data={"url": "example.com"},
+            )
+        )
+
+        # Send an encrypted event
+        # I know there'd normally be set-up of an encrypted room first
+        # but this will do for our purposes
+        self.helper.send_event(
+            room,
+            "m.room.encrypted",
+            content={
+                "algorithm": "m.megolm.v1.aes-sha2",
+                "sender_key": "6lImKbzK51MzWLwHh8tUM3UBBSBrLlgup/OOCGTvumM",
+                "ciphertext": "AwgAErABoRxwpMipdgiwXgu46rHiWQ0DmRj0qUlPrMraBUDk"
+                "leTnJRljpuc7IOhsYbLY3uo2WI0ab/ob41sV+3JEIhODJPqH"
+                "TK7cEZaIL+/up9e+dT9VGF5kRTWinzjkeqO8FU5kfdRjm+3w"
+                "0sy3o1OCpXXCfO+faPhbV/0HuK4ndx1G+myNfK1Nk/CxfMcT"
+                "BT+zDS/Df/QePAHVbrr9uuGB7fW8ogW/ulnydgZPRluusFGv"
+                "J3+cg9LoPpZPAmv5Me3ec7NtdlfN0oDZ0gk3TiNkkhsxDG9Y"
+                "YcNzl78USI0q8+kOV26Bu5dOBpU4WOuojXZHJlP5lMgdzLLl"
+                "EQ0",
+                "session_id": "IigqfNWLL+ez/Is+Duwp2s4HuCZhFG9b9CZKTYHtQ4A",
+                "device_id": "AHQDUSTAAA",
+            },
+            tok=other_access_token,
+        )
+
+        # Advance time a bit, so the pusher will register something has happened
+        self.pump()
+
+        # Make the push succeed
+        self.push_attempts[0][0].callback({})
+        self.pump()
+
+        # Check our push made it with high priority
+        self.assertEqual(len(self.push_attempts), 1)
+        self.assertEqual(self.push_attempts[0][1], "example.com")
+        self.assertEqual(self.push_attempts[0][2]["notification"]["prio"], "high")
+
+        # Add yet another person — we want to make this room not a 1:1
+        # (as encrypted messages in a 1:1 currently have tweaks applied
+        #  so it doesn't properly exercise the condition of all encrypted
+        #  messages need to be high).
+        self.helper.join(
+            room=room, user=yet_another_user_id, tok=yet_another_access_token
+        )
+
+        # Check no push notifications are sent regarding the membership changes
+        # (that would confuse the test)
+        self.pump()
+        self.assertEqual(len(self.push_attempts), 1)
+
+        # Send another encrypted event
+        self.helper.send_event(
+            room,
+            "m.room.encrypted",
+            content={
+                "ciphertext": "AwgAEoABtEuic/2DF6oIpNH+q/PonzlhXOVho8dTv0tzFr5m"
+                "9vTo50yabx3nxsRlP2WxSqa8I07YftP+EKWCWJvTkg6o7zXq"
+                "6CK+GVvLQOVgK50SfvjHqJXN+z1VEqj+5mkZVN/cAgJzoxcH"
+                "zFHkwDPJC8kQs47IHd8EO9KBUK4v6+NQ1uE/BIak4qAf9aS/"
+                "kI+f0gjn9IY9K6LXlah82A/iRyrIrxkCkE/n0VfvLhaWFecC"
+                "sAWTcMLoF6fh1Jpke95mljbmFSpsSd/eEQw",
+                "device_id": "SRCFTWTHXO",
+                "session_id": "eMA+bhGczuTz1C5cJR1YbmrnnC6Goni4lbvS5vJ1nG4",
+                "algorithm": "m.megolm.v1.aes-sha2",
+                "sender_key": "rC/XSIAiYrVGSuaHMop8/pTZbku4sQKBZwRwukgnN1c",
+            },
+            tok=other_access_token,
+        )
+
+        # Advance time a bit, so the pusher will register something has happened
+        self.pump()
+        self.assertEqual(len(self.push_attempts), 2)
+        self.assertEqual(self.push_attempts[1][1], "example.com")
+        self.assertEqual(self.push_attempts[1][2]["notification"]["prio"], "high")
+
+    def test_sends_high_priority_for_one_to_one_only(self):
+        """
+        The HTTP pusher will send pushes at high priority if they correspond
+        to a message in a one-to-one room.
+        """
+        # Register the user who gets notified
+        user_id = self.register_user("user", "pass")
+        access_token = self.login("user", "pass")
+
+        # Register the user who sends the message
+        other_user_id = self.register_user("otheruser", "pass")
+        other_access_token = self.login("otheruser", "pass")
+
+        # Register a third user
+        yet_another_user_id = self.register_user("yetanotheruser", "pass")
+        yet_another_access_token = self.login("yetanotheruser", "pass")
+
+        # Create a room
+        room = self.helper.create_room_as(user_id, tok=access_token)
+
+        # The other user joins
+        self.helper.join(room=room, user=other_user_id, tok=other_access_token)
+
+        # Register the pusher
+        user_tuple = self.get_success(
+            self.hs.get_datastore().get_user_by_access_token(access_token)
+        )
+        token_id = user_tuple["token_id"]
+
+        self.get_success(
+            self.hs.get_pusherpool().add_pusher(
+                user_id=user_id,
+                access_token=token_id,
+                kind="http",
+                app_id="m.http",
+                app_display_name="HTTP Push Notifications",
+                device_display_name="pushy push",
+                pushkey="a@example.com",
+                lang=None,
+                data={"url": "example.com"},
+            )
+        )
+
+        # Send a message
+        self.helper.send(room, body="Hi!", tok=other_access_token)
+
+        # Advance time a bit, so the pusher will register something has happened
+        self.pump()
+
+        # Make the push succeed
+        self.push_attempts[0][0].callback({})
+        self.pump()
+
+        # Check our push made it with high priority — this is a one-to-one room
+        self.assertEqual(len(self.push_attempts), 1)
+        self.assertEqual(self.push_attempts[0][1], "example.com")
+        self.assertEqual(self.push_attempts[0][2]["notification"]["prio"], "high")
+
+        # Yet another user joins
+        self.helper.join(
+            room=room, user=yet_another_user_id, tok=yet_another_access_token
+        )
+
+        # Check no push notifications are sent regarding the membership changes
+        # (that would confuse the test)
+        self.pump()
+        self.assertEqual(len(self.push_attempts), 1)
+
+        # Send another event
+        self.helper.send(room, body="Welcome!", tok=other_access_token)
+
+        # Advance time a bit, so the pusher will register something has happened
+        self.pump()
+        self.assertEqual(len(self.push_attempts), 2)
+        self.assertEqual(self.push_attempts[1][1], "example.com")
+
+        # check that this is low-priority
+        self.assertEqual(self.push_attempts[1][2]["notification"]["prio"], "low")
+
+    def test_sends_high_priority_for_mention(self):
+        """
+        The HTTP pusher will send pushes at high priority if they correspond
+        to a message containing the user's display name.
+        """
+        # Register the user who gets notified
+        user_id = self.register_user("user", "pass")
+        access_token = self.login("user", "pass")
+
+        # Register the user who sends the message
+        other_user_id = self.register_user("otheruser", "pass")
+        other_access_token = self.login("otheruser", "pass")
+
+        # Register a third user
+        yet_another_user_id = self.register_user("yetanotheruser", "pass")
+        yet_another_access_token = self.login("yetanotheruser", "pass")
+
+        # Create a room
+        room = self.helper.create_room_as(user_id, tok=access_token)
+
+        # The other users join
+        self.helper.join(room=room, user=other_user_id, tok=other_access_token)
+        self.helper.join(
+            room=room, user=yet_another_user_id, tok=yet_another_access_token
+        )
+
+        # Register the pusher
+        user_tuple = self.get_success(
+            self.hs.get_datastore().get_user_by_access_token(access_token)
+        )
+        token_id = user_tuple["token_id"]
+
+        self.get_success(
+            self.hs.get_pusherpool().add_pusher(
+                user_id=user_id,
+                access_token=token_id,
+                kind="http",
+                app_id="m.http",
+                app_display_name="HTTP Push Notifications",
+                device_display_name="pushy push",
+                pushkey="a@example.com",
+                lang=None,
+                data={"url": "example.com"},
+            )
+        )
+
+        # Send a message
+        self.helper.send(room, body="Oh, user, hello!", tok=other_access_token)
+
+        # Advance time a bit, so the pusher will register something has happened
+        self.pump()
+
+        # Make the push succeed
+        self.push_attempts[0][0].callback({})
+        self.pump()
+
+        # Check our push made it with high priority
+        self.assertEqual(len(self.push_attempts), 1)
+        self.assertEqual(self.push_attempts[0][1], "example.com")
+        self.assertEqual(self.push_attempts[0][2]["notification"]["prio"], "high")
+
+        # Send another event, this time with no mention
+        self.helper.send(room, body="Are you there?", tok=other_access_token)
+
+        # Advance time a bit, so the pusher will register something has happened
+        self.pump()
+        self.assertEqual(len(self.push_attempts), 2)
+        self.assertEqual(self.push_attempts[1][1], "example.com")
+
+        # check that this is low-priority
+        self.assertEqual(self.push_attempts[1][2]["notification"]["prio"], "low")
+
+    def test_sends_high_priority_for_atroom(self):
+        """
+        The HTTP pusher will send pushes at high priority if they correspond
+        to a message that contains @room.
+        """
+        # Register the user who gets notified
+        user_id = self.register_user("user", "pass")
+        access_token = self.login("user", "pass")
+
+        # Register the user who sends the message
+        other_user_id = self.register_user("otheruser", "pass")
+        other_access_token = self.login("otheruser", "pass")
+
+        # Register a third user
+        yet_another_user_id = self.register_user("yetanotheruser", "pass")
+        yet_another_access_token = self.login("yetanotheruser", "pass")
+
+        # Create a room (as other_user so the power levels are compatible with
+        # other_user sending @room).
+        room = self.helper.create_room_as(other_user_id, tok=other_access_token)
+
+        # The other users join
+        self.helper.join(room=room, user=user_id, tok=access_token)
+        self.helper.join(
+            room=room, user=yet_another_user_id, tok=yet_another_access_token
+        )
+
+        # Register the pusher
+        user_tuple = self.get_success(
+            self.hs.get_datastore().get_user_by_access_token(access_token)
+        )
+        token_id = user_tuple["token_id"]
+
+        self.get_success(
+            self.hs.get_pusherpool().add_pusher(
+                user_id=user_id,
+                access_token=token_id,
+                kind="http",
+                app_id="m.http",
+                app_display_name="HTTP Push Notifications",
+                device_display_name="pushy push",
+                pushkey="a@example.com",
+                lang=None,
+                data={"url": "example.com"},
+            )
+        )
+
+        # Send a message
+        self.helper.send(
+            room,
+            body="@room eeek! There's a spider on the table!",
+            tok=other_access_token,
+        )
+
+        # Advance time a bit, so the pusher will register something has happened
+        self.pump()
+
+        # Make the push succeed
+        self.push_attempts[0][0].callback({})
+        self.pump()
+
+        # Check our push made it with high priority
+        self.assertEqual(len(self.push_attempts), 1)
+        self.assertEqual(self.push_attempts[0][1], "example.com")
+        self.assertEqual(self.push_attempts[0][2]["notification"]["prio"], "high")
+
+        # Send another event, this time as someone without the power of @room
+        self.helper.send(
+            room, body="@room the spider is gone", tok=yet_another_access_token
+        )
+
+        # Advance time a bit, so the pusher will register something has happened
+        self.pump()
+        self.assertEqual(len(self.push_attempts), 2)
+        self.assertEqual(self.push_attempts[1][1], "example.com")
+
+        # check that this is low-priority
+        self.assertEqual(self.push_attempts[1][2]["notification"]["prio"], "low")