Neilj/fix autojoin (#4223)

* Fix auto join failures for servers that require user consent

* Fix auto join failures for servers that require user consent

5 files changed, 36 insertions, 3 deletions

diff --git a/changelog.d/4223.bugfix b/changelog.d/4223.bugfix
new file mode 100644
index 0000000000..bab591a765
--- /dev/null
+++ b/changelog.d/4223.bugfix
@@ -0,0 +1 @@
+Fix auto join failures for servers that require user consent
diff --git a/synapse/handlers/register.py b/synapse/handlers/register.py
index d2beb275cf..015909bb26 100644
--- a/synapse/handlers/register.py
+++ b/synapse/handlers/register.py
@@ -217,7 +217,19 @@ class RegistrationHandler(BaseHandler):
                     user_id = None
                     token = None
                     attempts += 1
+        if not self.hs.config.user_consent_at_registration:
+            yield self._auto_join_rooms(user_id)
 
+        defer.returnValue((user_id, token))
+
+    @defer.inlineCallbacks
+    def _auto_join_rooms(self, user_id):
+        """Automatically joins users to auto join rooms - creating the room in the first place
+        if the user is the first to be created.
+
+        Args:
+            user_id(str): The user to join
+        """
         # auto-join the user to any rooms we're supposed to dump them into
         fake_requester = create_requester(user_id)
 
@@ -226,7 +238,6 @@ class RegistrationHandler(BaseHandler):
         if self.hs.config.autocreate_auto_join_rooms:
             count = yield self.store.count_all_users()
             should_auto_create_rooms = count == 1
-
         for r in self.hs.config.auto_join_rooms:
             try:
                 if should_auto_create_rooms:
@@ -256,7 +267,15 @@ class RegistrationHandler(BaseHandler):
             except Exception as e:
                 logger.error("Failed to join new user to %r: %r", r, e)
 
-        defer.returnValue((user_id, token))
+    @defer.inlineCallbacks
+    def post_consent_actions(self, user_id):
+        """A series of registration actions that can only be carried out once consent
+        has been granted
+
+        Args:
+            user_id (str): The user to join
+        """
+        yield self._auto_join_rooms(user_id)
 
     @defer.inlineCallbacks
     def appservice_register(self, user_localpart, as_token):
diff --git a/synapse/rest/client/v2_alpha/register.py b/synapse/rest/client/v2_alpha/register.py
index 0515715f7c..aec0c6b075 100644
--- a/synapse/rest/client/v2_alpha/register.py
+++ b/synapse/rest/client/v2_alpha/register.py
@@ -457,6 +457,7 @@ class RegisterRestServlet(RestServlet):
             yield self.store.user_set_consent_version(
                 registered_user_id, self.hs.config.user_consent_version,
             )
+            yield self.registration_handler.post_consent_actions(registered_user_id)
 
         defer.returnValue((200, return_dict))
 
diff --git a/synapse/rest/consent/consent_resource.py b/synapse/rest/consent/consent_resource.py
index ad525b22e1..80611cfe84 100644
--- a/synapse/rest/consent/consent_resource.py
+++ b/synapse/rest/consent/consent_resource.py
@@ -89,6 +89,7 @@ class ConsentResource(Resource):
 
         self.hs = hs
         self.store = hs.get_datastore()
+        self.registration_handler = hs.get_handlers().registration_handler
 
         # this is required by the request_handler wrapper
         self.clock = hs.get_clock()
@@ -199,6 +200,7 @@ class ConsentResource(Resource):
             if e.code != 404:
                 raise
             raise NotFoundError("Unknown user")
+        yield self.registration_handler.post_consent_actions(qualified_user_id)
 
         try:
             self._render_template(request, "success.html")
diff --git a/tests/handlers/test_register.py b/tests/handlers/test_register.py
index 3e9a190727..90a2a76475 100644
--- a/tests/handlers/test_register.py
+++ b/tests/handlers/test_register.py
@@ -150,7 +150,6 @@ class RegistrationTestCase(unittest.TestCase):
         self.hs.config.auto_join_rooms = [room_alias_str]
         res = yield self.handler.register(localpart='jeff')
         rooms = yield self.store.get_rooms_for_user(res[0])
-
         directory_handler = self.hs.get_handlers().directory_handler
         room_alias = RoomAlias.from_string(room_alias_str)
         room_id = yield directory_handler.get_association(room_alias)
@@ -184,3 +183,14 @@ class RegistrationTestCase(unittest.TestCase):
         res = yield self.handler.register(localpart='jeff')
         rooms = yield self.store.get_rooms_for_user(res[0])
         self.assertEqual(len(rooms), 0)
+
+    @defer.inlineCallbacks
+    def test_auto_create_auto_join_where_no_consent(self):
+        self.hs.config.user_consent_at_registration = True
+        self.hs.config.block_events_without_consent_error = "Error"
+        room_alias_str = "#room:test"
+        self.hs.config.auto_join_rooms = [room_alias_str]
+        res = yield self.handler.register(localpart='jeff')
+        yield self.handler.post_consent_actions(res[0])
+        rooms = yield self.store.get_rooms_for_user(res[0])
+        self.assertEqual(len(rooms), 0)