Merge pull request #3667 from matrix-org/erikj/fixup_unbind

Don't fail requests to unbind 3pids for non supporting ID servers

changelog.d/3661.bugfix

@@ -0,0 +1 @@
+Fix bug on deleting 3pid when using identity servers that don't support unbind API

synapse/handlers/auth.py

@@ -828,23 +828,37 @@ def add_threepid(self, user_id, medium, address, validated_at):
 
     @defer.inlineCallbacks
     def delete_threepid(self, user_id, medium, address):
+        """Attempts to unbind the 3pid on the identity servers and deletes it
+        from the local database.
+
+        Args:
+            user_id (str)
+            medium (str)
+            address (str)
+
+        Returns:
+            Deferred[bool]: Returns True if successfully unbound the 3pid on
+            the identity server, False if identity server doesn't support the
+            unbind API.
+        """
+
         # 'Canonicalise' email addresses as per above
         if medium == 'email':
             address = address.lower()
 
         identity_handler = self.hs.get_handlers().identity_handler
-        yield identity_handler.unbind_threepid(
+        result = yield identity_handler.try_unbind_threepid(
             user_id,
             {
                 'medium': medium,
                 'address': address,
             },
         )
 
-        ret = yield self.store.user_delete_threepid(
+        yield self.store.user_delete_threepid(
             user_id, medium, address,
         )
-        defer.returnValue(ret)
+        defer.returnValue(result)
 
     def _save_session(self, session):
         # TODO: Persistent storage

synapse/handlers/deactivate_account.py

@@ -51,7 +51,8 @@ def deactivate_account(self, user_id, erase_data):
             erase_data (bool): whether to GDPR-erase the user's data
 
         Returns:
-            Deferred
+            Deferred[bool]: True if identity server supports removing
+            threepids, otherwise False.
         """
         # FIXME: Theoretically there is a race here wherein user resets
         # password using threepid.
@@ -60,16 +61,22 @@ def deactivate_account(self, user_id, erase_data):
         # leave the user still active so they can try again.
         # Ideally we would prevent password resets and then do this in the
         # background thread.
+
+        # This will be set to false if the identity server doesn't support
+        # unbinding
+        identity_server_supports_unbinding = True
+
         threepids = yield self.store.user_get_threepids(user_id)
         for threepid in threepids:
             try:
-                yield self._identity_handler.unbind_threepid(
+                result = yield self._identity_handler.try_unbind_threepid(
                     user_id,
                     {
                         'medium': threepid['medium'],
                         'address': threepid['address'],
                     },
                 )
+                identity_server_supports_unbinding &= result
             except Exception:
                 # Do we want this to be a fatal error or should we carry on?
                 logger.exception("Failed to remove threepid from ID server")
@@ -103,6 +110,8 @@ def deactivate_account(self, user_id, erase_data):
         # parts users from rooms (if it isn't already running)
         self._start_user_parting()
 
+        defer.returnValue(identity_server_supports_unbinding)
+
     def _start_user_parting(self):
         """
         Start the process that goes through the table of users

synapse/handlers/identity.py

@@ -137,15 +137,19 @@ def bind_threepid(self, creds, mxid):
         defer.returnValue(data)
 
     @defer.inlineCallbacks
-    def unbind_threepid(self, mxid, threepid):
-        """
-        Removes a binding from an identity server
+    def try_unbind_threepid(self, mxid, threepid):
+        """Removes a binding from an identity server
+
         Args:
             mxid (str): Matrix user ID of binding to be removed
             threepid (dict): Dict with medium & address of binding to be removed
 
+        Raises:
+            SynapseError: If we failed to contact the identity server
+
         Returns:
-            Deferred[bool]: True on success, otherwise False
+            Deferred[bool]: True on success, otherwise False if the identity
+            server doesn't support unbinding
         """
         logger.debug("unbinding threepid %r from %s", threepid, mxid)
         if not self.trusted_id_servers:
@@ -175,11 +179,21 @@ def unbind_threepid(self, mxid, threepid):
             content=content,
             destination_is=id_server,
         )
-        yield self.http_client.post_json_get_json(
-            url,
-            content,
-            headers,
-        )
+        try:
+            yield self.http_client.post_json_get_json(
+                url,
+                content,
+                headers,
+            )
+        except HttpResponseException as e:
+            if e.code in (400, 404, 501,):
+                # The remote server probably doesn't support unbinding (yet)
+                logger.warn("Received %d response while unbinding threepid", e.code)
+                defer.returnValue(False)
+            else:
+                logger.error("Failed to unbind threepid on identity server: %s", e)
+                raise SynapseError(502, "Failed to contact identity server")
+
         defer.returnValue(True)
 
     @defer.inlineCallbacks

synapse/rest/client/v1/admin.py

@@ -391,10 +391,17 @@ def on_POST(self, request, target_user_id):
         if not is_admin:
             raise AuthError(403, "You are not a server admin")
 
-        yield self._deactivate_account_handler.deactivate_account(
+        result = yield self._deactivate_account_handler.deactivate_account(
             target_user_id, erase,
         )
-        defer.returnValue((200, {}))
+        if result:
+            id_server_unbind_result = "success"
+        else:
+            id_server_unbind_result = "no-support"
+
+        defer.returnValue((200, {
+            "id_server_unbind_result": id_server_unbind_result,
+        }))
 
 
 class ShutdownRoomRestServlet(ClientV1RestServlet):

synapse/rest/client/v2_alpha/account.py

@@ -209,10 +209,17 @@ def on_POST(self, request):
         yield self.auth_handler.validate_user_via_ui_auth(
             requester, body, self.hs.get_ip_from_request(request),
         )
-        yield self._deactivate_account_handler.deactivate_account(
+        result = yield self._deactivate_account_handler.deactivate_account(
             requester.user.to_string(), erase,
         )
-        defer.returnValue((200, {}))
+        if result:
+            id_server_unbind_result = "success"
+        else:
+            id_server_unbind_result = "no-support"
+
+        defer.returnValue((200, {
+            "id_server_unbind_result": id_server_unbind_result,
+        }))
 
 
 class EmailThreepidRequestTokenRestServlet(RestServlet):
@@ -364,7 +371,7 @@ def on_POST(self, request):
         user_id = requester.user.to_string()
 
         try:
-            yield self.auth_handler.delete_threepid(
+            ret = yield self.auth_handler.delete_threepid(
                 user_id, body['medium'], body['address']
             )
         except Exception:
@@ -374,7 +381,14 @@ def on_POST(self, request):
             logger.exception("Failed to remove threepid")
             raise SynapseError(500, "Failed to remove threepid")
 
-        defer.returnValue((200, {}))
+        if ret:
+            id_server_unbind_result = "success"
+        else:
+            id_server_unbind_result = "no-support"
+
+        defer.returnValue((200, {
+            "id_server_unbind_result": id_server_unbind_result,
+        }))
 
 
 class WhoamiRestServlet(RestServlet):