Use parse_{int,str} and assert from http.servlet

parse_integer and parse_string can take a request and raise errors
in case we have wrong or missing params.
This PR tries to use them more to deduplicate some code and make it
better readable

7 files changed, 43 insertions, 75 deletions

diff --git a/synapse/rest/client/v1/admin.py b/synapse/rest/client/v1/admin.py
index 2b091d61a5..6b3c496418 100644
--- a/synapse/rest/client/v1/admin.py
+++ b/synapse/rest/client/v1/admin.py
@@ -22,7 +22,12 @@ from twisted.internet import defer
 
 from synapse.api.constants import Membership
 from synapse.api.errors import AuthError, Codes, NotFoundError, SynapseError
-from synapse.http.servlet import parse_json_object_from_request
+from synapse.http.servlet import (
+    assert_params_in_request,
+    parse_json_object_from_request,
+    parse_integer,
+    parse_string
+)
 from synapse.types import UserID, create_requester
 
 from .base import ClientV1RestServlet, client_path_patterns
@@ -98,16 +103,8 @@ class PurgeMediaCacheRestServlet(ClientV1RestServlet):
         if not is_admin:
             raise AuthError(403, "You are not a server admin")
 
-        before_ts = request.args.get("before_ts", None)
-        if not before_ts:
-            raise SynapseError(400, "Missing 'before_ts' arg")
-
-        logger.info("before_ts: %r", before_ts[0])
-
-        try:
-            before_ts = int(before_ts[0])
-        except Exception:
-            raise SynapseError(400, "Invalid 'before_ts' arg")
+        before_ts = parse_integer(request, "before_ts", required=True)
+        logger.info("before_ts: %r", before_ts)
 
         ret = yield self.media_repository.delete_old_remote_media(before_ts)
 
@@ -300,10 +297,8 @@ class ShutdownRoomRestServlet(ClientV1RestServlet):
             raise AuthError(403, "You are not a server admin")
 
         content = parse_json_object_from_request(request)
-
-        new_room_user_id = content.get("new_room_user_id")
-        if not new_room_user_id:
-            raise SynapseError(400, "Please provide field `new_room_user_id`")
+        assert_params_in_request(content, ["new_room_user_id"])
+        new_room_user_id = content["new_room_user_id"]
 
         room_creator_requester = create_requester(new_room_user_id)
 
@@ -464,9 +459,8 @@ class ResetPasswordRestServlet(ClientV1RestServlet):
             raise AuthError(403, "You are not a server admin")
 
         params = parse_json_object_from_request(request)
+        assert_params_in_request(params, ["new_password"])
         new_password = params['new_password']
-        if not new_password:
-            raise SynapseError(400, "Missing 'new_password' arg")
 
         logger.info("new_password: %r", new_password)
 
@@ -514,12 +508,9 @@ class GetUsersPaginatedRestServlet(ClientV1RestServlet):
             raise SynapseError(400, "Can only users a local user")
 
         order = "name"  # order by name in user table
-        start = request.args.get("start")[0]
-        limit = request.args.get("limit")[0]
-        if not limit:
-            raise SynapseError(400, "Missing 'limit' arg")
-        if not start:
-            raise SynapseError(400, "Missing 'start' arg")
+        start = parse_integer(request, "start", required=True)
+        limit = parse_integer(request, "limit", required=True)
+
         logger.info("limit: %s, start: %s", limit, start)
 
         ret = yield self.handlers.admin_handler.get_users_paginate(
@@ -551,12 +542,9 @@ class GetUsersPaginatedRestServlet(ClientV1RestServlet):
 
         order = "name"  # order by name in user table
         params = parse_json_object_from_request(request)
+        assert_params_in_request(params, ["limit", "start"])
         limit = params['limit']
         start = params['start']
-        if not limit:
-            raise SynapseError(400, "Missing 'limit' arg")
-        if not start:
-            raise SynapseError(400, "Missing 'start' arg")
         logger.info("limit: %s, start: %s", limit, start)
 
         ret = yield self.handlers.admin_handler.get_users_paginate(
@@ -604,10 +592,7 @@ class SearchUsersRestServlet(ClientV1RestServlet):
         if not self.hs.is_mine(target_user):
             raise SynapseError(400, "Can only users a local user")
 
-        term = request.args.get("term")[0]
-        if not term:
-            raise SynapseError(400, "Missing 'term' arg")
-
+        term = parse_string(request, "term", required=True)
         logger.info("term: %s ", term)
 
         ret = yield self.handlers.admin_handler.search_users(
diff --git a/synapse/rest/client/v1/directory.py b/synapse/rest/client/v1/directory.py
index 4fdbb83815..3003cde94e 100644
--- a/synapse/rest/client/v1/directory.py
+++ b/synapse/rest/client/v1/directory.py
@@ -18,8 +18,8 @@ import logging
 
 from twisted.internet import defer
 
-from synapse.api.errors import AuthError, Codes, SynapseError
-from synapse.http.servlet import parse_json_object_from_request
+from synapse.api.errors import AuthError, SynapseError
+from synapse.http.servlet import assert_params_in_request, parse_json_object_from_request
 from synapse.types import RoomAlias
 
 from .base import ClientV1RestServlet, client_path_patterns
@@ -52,15 +52,14 @@ class ClientDirectoryServer(ClientV1RestServlet):
 
     @defer.inlineCallbacks
     def on_PUT(self, request, room_alias):
+        room_alias = RoomAlias.from_string(room_alias)
+
         content = parse_json_object_from_request(request)
         if "room_id" not in content:
-            raise SynapseError(400, "Missing room_id key",
+            raise SynapseError(400, 'Missing params: ["room_id"]',
                                errcode=Codes.BAD_JSON)
 
         logger.debug("Got content: %s", content)
-
-        room_alias = RoomAlias.from_string(room_alias)
-
         logger.debug("Got room name: %s", room_alias.to_string())
 
         room_id = content["room_id"]
diff --git a/synapse/rest/client/v1/initial_sync.py b/synapse/rest/client/v1/initial_sync.py
index fbe8cb2023..00a1a99feb 100644
--- a/synapse/rest/client/v1/initial_sync.py
+++ b/synapse/rest/client/v1/initial_sync.py
@@ -16,6 +16,7 @@
 from twisted.internet import defer
 
 from synapse.streams.config import PaginationConfig
+from synapse.http.servlet import parse_boolean
 
 from .base import ClientV1RestServlet, client_path_patterns
 
@@ -33,7 +34,7 @@ class InitialSyncRestServlet(ClientV1RestServlet):
         requester = yield self.auth.get_user_by_req(request)
         as_client_event = "raw" not in request.args
         pagination_config = PaginationConfig.from_request(request)
-        include_archived = request.args.get("archived", None) == ["true"]
+        include_archived = parse_boolean(request, "archived", default=False)
         content = yield self.initial_sync_handler.snapshot_all_rooms(
             user_id=requester.user.to_string(),
             pagin_config=pagination_config,
diff --git a/synapse/rest/client/v1/push_rule.py b/synapse/rest/client/v1/push_rule.py
index 0df7ce570f..7cf6a99774 100644
--- a/synapse/rest/client/v1/push_rule.py
+++ b/synapse/rest/client/v1/push_rule.py
@@ -21,7 +21,7 @@ from synapse.api.errors import (
     SynapseError,
     UnrecognizedRequestError,
 )
-from synapse.http.servlet import parse_json_value_from_request
+from synapse.http.servlet import parse_json_value_from_request, parse_string
 from synapse.push.baserules import BASE_RULE_IDS
 from synapse.push.clientformat import format_push_rules_for_user
 from synapse.push.rulekinds import PRIORITY_CLASS_MAP
@@ -75,11 +75,11 @@ class PushRuleRestServlet(ClientV1RestServlet):
         except InvalidRuleException as e:
             raise SynapseError(400, e.message)
 
-        before = request.args.get("before", None)
+        before = parse_string(request, "before")
         if before:
             before = _namespaced_rule_id(spec, before[0])
 
-        after = request.args.get("after", None)
+        after = parse_string(request, "after")
         if after:
             after = _namespaced_rule_id(spec, after[0])
 
diff --git a/synapse/rest/client/v1/pusher.py b/synapse/rest/client/v1/pusher.py
index 1581f88db5..95b9252b61 100644
--- a/synapse/rest/client/v1/pusher.py
+++ b/synapse/rest/client/v1/pusher.py
@@ -21,6 +21,7 @@ from synapse.api.errors import Codes, StoreError, SynapseError
 from synapse.http.server import finish_request
 from synapse.http.servlet import (
     RestServlet,
+    assert_params_in_request,
     parse_json_object_from_request,
     parse_string,
 )
@@ -91,15 +92,11 @@ class PushersSetRestServlet(ClientV1RestServlet):
             )
             defer.returnValue((200, {}))
 
-        reqd = ['kind', 'app_id', 'app_display_name',
-                'device_display_name', 'pushkey', 'lang', 'data']
-        missing = []
-        for i in reqd:
-            if i not in content:
-                missing.append(i)
-        if len(missing):
-            raise SynapseError(400, "Missing parameters: " + ','.join(missing),
-                               errcode=Codes.MISSING_PARAM)
+        assert_params_in_request(
+            content,
+            ['kind', 'app_id', 'app_display_name',
+             'device_display_name', 'pushkey', 'lang', 'data']
+        )
 
         logger.debug("set pushkey %s to kind %s", content['pushkey'], content['kind'])
         logger.debug("Got pushers request with body: %r", content)
@@ -148,7 +145,7 @@ class PushersRemoveRestServlet(RestServlet):
     SUCCESS_HTML = "<html><body>You have been unsubscribed</body><html>"
 
     def __init__(self, hs):
-        super(RestServlet, self).__init__()
+        super(PushersRemoveRestServlet, self).__init__()
         self.hs = hs
         self.notifier = hs.get_notifier()
         self.auth = hs.get_auth()
diff --git a/synapse/rest/client/v1/register.py b/synapse/rest/client/v1/register.py
index 3ce5f8b726..744ed04455 100644
--- a/synapse/rest/client/v1/register.py
+++ b/synapse/rest/client/v1/register.py
@@ -18,15 +18,13 @@ import hmac
 import logging
 from hashlib import sha1
 
-from six import string_types
-
 from twisted.internet import defer
 
 import synapse.util.stringutils as stringutils
 from synapse.api.auth import get_access_token_from_request
 from synapse.api.constants import LoginType
 from synapse.api.errors import Codes, SynapseError
-from synapse.http.servlet import parse_json_object_from_request
+from synapse.http.servlet import assert_params_in_request, parse_json_object_from_request
 from synapse.types import create_requester
 
 from .base import ClientV1RestServlet, client_path_patterns
@@ -124,8 +122,7 @@ class RegisterRestServlet(ClientV1RestServlet):
         session = (register_json["session"]
                    if "session" in register_json else None)
         login_type = None
-        if "type" not in register_json:
-            raise SynapseError(400, "Missing 'type' key.")
+        assert_params_in_request(register_json, ["type"])
 
         try:
             login_type = register_json["type"]
@@ -312,9 +309,7 @@ class RegisterRestServlet(ClientV1RestServlet):
     def _do_app_service(self, request, register_json, session):
         as_token = get_access_token_from_request(request)
 
-        if "user" not in register_json:
-            raise SynapseError(400, "Expected 'user' key.")
-
+        assert_params_in_request(register_json, ["user"])
         user_localpart = register_json["user"].encode("utf-8")
 
         handler = self.handlers.registration_handler
@@ -331,12 +326,7 @@ class RegisterRestServlet(ClientV1RestServlet):
 
     @defer.inlineCallbacks
     def _do_shared_secret(self, request, register_json, session):
-        if not isinstance(register_json.get("mac", None), string_types):
-            raise SynapseError(400, "Expected mac.")
-        if not isinstance(register_json.get("user", None), string_types):
-            raise SynapseError(400, "Expected 'user' key.")
-        if not isinstance(register_json.get("password", None), string_types):
-            raise SynapseError(400, "Expected 'password' key.")
+        assert_params_in_request(register_json, ["mac", "user", "password"])
 
         if not self.hs.config.registration_shared_secret:
             raise SynapseError(400, "Shared secret registration is not enabled")
@@ -419,11 +409,7 @@ class CreateUserRestServlet(ClientV1RestServlet):
 
     @defer.inlineCallbacks
     def _do_create(self, requester, user_json):
-        if "localpart" not in user_json:
-            raise SynapseError(400, "Expected 'localpart' key.")
-
-        if "displayname" not in user_json:
-            raise SynapseError(400, "Expected 'displayname' key.")
+        assert_params_in_request(user_json, ["localpart", "displayname"])
 
         localpart = user_json["localpart"].encode("utf-8")
         displayname = user_json["displayname"].encode("utf-8")
diff --git a/synapse/rest/client/v1/room.py b/synapse/rest/client/v1/room.py
index 2470db52ba..3050d040a2 100644
--- a/synapse/rest/client/v1/room.py
+++ b/synapse/rest/client/v1/room.py
@@ -28,6 +28,7 @@ from synapse.api.errors import AuthError, Codes, SynapseError
 from synapse.api.filtering import Filter
 from synapse.events.utils import format_event_for_client_v2, serialize_event
 from synapse.http.servlet import (
+    assert_params_in_request,
     parse_integer,
     parse_json_object_from_request,
     parse_string,
@@ -435,7 +436,7 @@ class RoomMessageListRestServlet(ClientV1RestServlet):
             request, default_limit=10,
         )
         as_client_event = "raw" not in request.args
-        filter_bytes = request.args.get("filter", None)
+        filter_bytes = parse_string(request, "filter")
         if filter_bytes:
             filter_json = urlparse.unquote(filter_bytes[-1]).decode("UTF-8")
             event_filter = Filter(json.loads(filter_json))
@@ -530,7 +531,7 @@ class RoomEventContextServlet(ClientV1RestServlet):
     def on_GET(self, request, room_id, event_id):
         requester = yield self.auth.get_user_by_req(request, allow_guest=True)
 
-        limit = int(request.args.get("limit", [10])[0])
+        limit = parse_integer(request, "limit", default=10)
 
         results = yield self.handlers.room_context_handler.get_event_context(
             requester.user,
@@ -636,8 +637,7 @@ class RoomMembershipRestServlet(ClientV1RestServlet):
 
         target = requester.user
         if membership_action in ["invite", "ban", "unban", "kick"]:
-            if "user_id" not in content:
-                raise SynapseError(400, "Missing user_id key.")
+            assert_params_in_request(content, ["user_id"])
             target = UserID.from_string(content["user_id"])
 
         event_content = None
@@ -764,7 +764,7 @@ class SearchRestServlet(ClientV1RestServlet):
 
         content = parse_json_object_from_request(request)
 
-        batch = request.args.get("next_batch", [None])[0]
+        batch = parse_string(request, "next_batch")
         results = yield self.handlers.search_handler.search(
             requester.user,
             content,