Remove duplicated error handling

Co-authored-by: Patrick Cloke <clokep@users.noreply.github.com>

docs/admin_api/user_admin_api.rst

@@ -432,7 +432,7 @@ when admins wish to do actions on behalf of a user.
 
 The API is::
 
-    PUT /_synapse/admin/v1/users/<user_id>/login
+    POST /_synapse/admin/v1/users/<user_id>/login
     {}
 
 An optional ``valid_until_ms`` field can be specified in the request body as an

synapse/api/auth_blocking.py

@@ -61,8 +61,14 @@ class AuthBlocking:
                 certain blocking reasons like MAU.
 
             requester: If present, and the authenticated entity is a user, checks for
-                presence against existing MAU cohort.
+                presence against existing MAU cohort. Passing in both a `user_id` and
+                `requester` is an error.
         """
+        if requester and user_id:
+            raise Exception(
+                "Passed in both 'user_id' and 'requester' to 'check_auth_blocking'"
+            )
+
         if requester:
             if requester.authenticated_entity.startswith("@"):
                 user_id = requester.authenticated_entity

synapse/handlers/register.py

@@ -376,11 +376,6 @@ class RegistrationHandler(BaseHandler):
                             action="join",
                             ratelimit=False,
                         )
-
-            except ConsentNotGivenError as e:
-                # Technically not necessary to pull out this error though
-                # moving away from bare excepts is a good thing to do.
-                logger.error("Failed to join new user to %r: %r", r, e)
             except Exception as e:
                 logger.error("Failed to join new user to %r: %r", r, e)
 

synapse/rest/admin/users.py

@@ -833,6 +833,16 @@ class UserMediaRestServlet(RestServlet):
 
 class UserTokenRestServlet(RestServlet):
     """An admin API for logging in as a user.
+
+    Example:
+
+        POST /_synapse/admin/v1/users/@test:example.com/login
+        {}
+
+        200 OK
+        {
+            "access_token": "<some_token>"
+        }
     """
 
     PATTERNS = admin_patterns("/users/(?P<user_id>[^/]*)/login$")
@@ -843,7 +853,7 @@ class UserTokenRestServlet(RestServlet):
         self.auth = hs.get_auth()
         self.auth_handler = hs.get_auth_handler()
 
-    async def on_PUT(self, request, user_id):
+    async def on_POST(self, request, user_id):
         requester = await self.auth.get_user_by_req(request)
         await assert_user_is_admin(self.auth, requester.user)
         auth_user = requester.user
@@ -851,7 +861,7 @@ class UserTokenRestServlet(RestServlet):
         if not self.hs.is_mine_id(user_id):
             raise SynapseError(400, "Only local users can be logged in as")
 
-        body = parse_json_object_from_request(request)
+        body = parse_json_object_from_request(request, allow_empty_body=True)
 
         valid_until_ms = body.get("valid_until_ms")
         if valid_until_ms and not isinstance(valid_until_ms, int):

tests/rest/admin/test_user.py

@@ -1550,7 +1550,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
 
     def _get_token(self) -> str:
         request, channel = self.make_request(
-            "PUT", self.url, b"{}", access_token=self.admin_user_tok
+            "POST", self.url, b"{}", access_token=self.admin_user_tok
         )
         self.render(request)
         self.assertEqual(200, int(channel.result["code"]), msg=channel.result["body"])
@@ -1559,7 +1559,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
     def test_no_auth(self):
         """Try to login as a user without authentication.
         """
-        request, channel = self.make_request("PUT", self.url, b"{}")
+        request, channel = self.make_request("POST", self.url, b"{}")
         self.render(request)
 
         self.assertEqual(401, int(channel.result["code"]), msg=channel.result["body"])
@@ -1569,7 +1569,7 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
         """Try to login as a user as a non-admin user.
         """
         request, channel = self.make_request(
-            "PUT", self.url, b"{}", access_token=self.other_user_tok
+            "POST", self.url, b"{}", access_token=self.other_user_tok
         )
         self.render(request)
 
@@ -1753,12 +1753,12 @@ class UserTokenRestTestCase(unittest.HomeserverTestCase):
         # Create a room as the admin user. This will bump the monthly active users to 1.
         room_id = self.helper.create_room_as(self.admin_user, tok=self.admin_user_tok)
 
-        # Trying to join as the other user should fail.
+        # Trying to join as the other user should fail due to reaching MAU limit.
         self.helper.join(
             room_id, user=self.other_user, tok=self.other_user_tok, expect_code=403
         )
 
         # Logging in as the other user and joining a room should work, even
-        # though they should be denied.
+        # though the MAU limit would stop the user doing so.
         puppet_token = self._get_token()
         self.helper.join(room_id, user=self.other_user, tok=puppet_token)