Add tests to characterise the current behaviour of R30 phone-home metrics (#10315)

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

changelog.d/10315.misc

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+Add tests to characterise the current behaviour of R30 phone-home metrics.

tests/app/test_phone_stats_home.py

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+import synapse
+from synapse.rest.client.v1 import login, room
+
+from tests import unittest
+from tests.unittest import HomeserverTestCase
+
+ONE_DAY_IN_SECONDS = 86400
+
+
+class PhoneHomeTestCase(HomeserverTestCase):
+    servlets = [
+        synapse.rest.admin.register_servlets_for_client_rest_resource,
+        room.register_servlets,
+        login.register_servlets,
+    ]
+
+    # Override the retention time for the user_ips table because otherwise it
+    # gets pruned too aggressively for our R30 test.
+    @unittest.override_config({"user_ips_max_age": "365d"})
+    def test_r30_minimum_usage(self):
+        """
+        Tests the minimum amount of interaction necessary for the R30 metric
+        to consider a user 'retained'.
+        """
+
+        # Register a user, log it in, create a room and send a message
+        user_id = self.register_user("u1", "secret!")
+        access_token = self.login("u1", "secret!")
+        room_id = self.helper.create_room_as(room_creator=user_id, tok=access_token)
+        self.helper.send(room_id, "message", tok=access_token)
+
+        # Check the R30 results do not count that user.
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 0})
+
+        # Advance 30 days (+ 1 second, because strict inequality causes issues if we are
+        # bang on 30 days later).
+        self.reactor.advance(30 * ONE_DAY_IN_SECONDS + 1)
+
+        # (Make sure the user isn't somehow counted by this point.)
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 0})
+
+        # Send a message (this counts as activity)
+        self.helper.send(room_id, "message2", tok=access_token)
+
+        # We have to wait some time for _update_client_ips_batch to get
+        # called and update the user_ips table.
+        self.reactor.advance(2 * 60 * 60)
+
+        # *Now* the user is counted.
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 1, "unknown": 1})
+
+        # Advance 29 days. The user has now not posted for 29 days.
+        self.reactor.advance(29 * ONE_DAY_IN_SECONDS)
+
+        # The user is still counted.
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 1, "unknown": 1})
+
+        # Advance another day. The user has now not posted for 30 days.
+        self.reactor.advance(ONE_DAY_IN_SECONDS)
+
+        # The user is now no longer counted in R30.
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 0})
+
+    def test_r30_minimum_usage_using_default_config(self):
+        """
+        Tests the minimum amount of interaction necessary for the R30 metric
+        to consider a user 'retained'.
+
+        N.B. This test does not override the `user_ips_max_age` config setting,
+        which defaults to 28 days.
+        """
+
+        # Register a user, log it in, create a room and send a message
+        user_id = self.register_user("u1", "secret!")
+        access_token = self.login("u1", "secret!")
+        room_id = self.helper.create_room_as(room_creator=user_id, tok=access_token)
+        self.helper.send(room_id, "message", tok=access_token)
+
+        # Check the R30 results do not count that user.
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 0})
+
+        # Advance 30 days (+ 1 second, because strict inequality causes issues if we are
+        # bang on 30 days later).
+        self.reactor.advance(30 * ONE_DAY_IN_SECONDS + 1)
+
+        # (Make sure the user isn't somehow counted by this point.)
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 0})
+
+        # Send a message (this counts as activity)
+        self.helper.send(room_id, "message2", tok=access_token)
+
+        # We have to wait some time for _update_client_ips_batch to get
+        # called and update the user_ips table.
+        self.reactor.advance(2 * 60 * 60)
+
+        # *Now* the user is counted.
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 1, "unknown": 1})
+
+        # Advance 27 days. The user has now not posted for 27 days.
+        self.reactor.advance(27 * ONE_DAY_IN_SECONDS)
+
+        # The user is still counted.
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 1, "unknown": 1})
+
+        # Advance another day. The user has now not posted for 28 days.
+        self.reactor.advance(ONE_DAY_IN_SECONDS)
+
+        # The user is now no longer counted in R30.
+        # (This is because the user_ips table has been pruned, which by default
+        # only preserves the last 28 days of entries.)
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 0})
+
+    def test_r30_user_must_be_retained_for_at_least_a_month(self):
+        """
+        Tests that a newly-registered user must be retained for a whole month
+        before appearing in the R30 statistic, even if they post every day
+        during that time!
+        """
+        # Register a user and send a message
+        user_id = self.register_user("u1", "secret!")
+        access_token = self.login("u1", "secret!")
+        room_id = self.helper.create_room_as(room_creator=user_id, tok=access_token)
+        self.helper.send(room_id, "message", tok=access_token)
+
+        # Check the user does not contribute to R30 yet.
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 0})
+
+        for _ in range(30):
+            # This loop posts a message every day for 30 days
+            self.reactor.advance(ONE_DAY_IN_SECONDS)
+            self.helper.send(room_id, "I'm still here", tok=access_token)
+
+            # Notice that the user *still* does not contribute to R30!
+            r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+            self.assertEqual(r30_results, {"all": 0})
+
+        self.reactor.advance(ONE_DAY_IN_SECONDS)
+        self.helper.send(room_id, "Still here!", tok=access_token)
+
+        # *Now* the user appears in R30.
+        r30_results = self.get_success(self.hs.get_datastore().count_r30_users())
+        self.assertEqual(r30_results, {"all": 1, "unknown": 1})