Combine the request wrappers in rest/media/v1 and http/server into a single wrapper decorator

synapse/http/server.py

@@ -57,9 +57,18 @@ _next_request_id = 0
 def request_handler(request_handler):
     """Wraps a method that acts as a request handler with the necessary logging
     and exception handling.
-    The method must have a signature of "handle_foo(self, request)".
-    The argument "self" must have "version_string" and "clock" attributes.
-    The argument "request" must be a twisted HTTP request.
+
+    The method must have a signature of "handle_foo(self, request)". The
+    argument "self" must have "version_string" and "clock" attributes. The
+    argument "request" must be a twisted HTTP request.
+
+    The method must return a deferred. If the deferred succeeds we assume that
+    a response has been sent. If the deferred fails with a SynapseError we use
+    it to send a JSON response with the appropriate HTTP reponse code. If the
+    deferred fails with any other type of error we send a 500 reponse.
+
+    We insert a unique request-id into the logging context for this request and
+    log the response and duration for this request.
     """
 
     @defer.inlineCallbacks

synapse/http/servlet.py

@@ -23,6 +23,61 @@ import logging
 logger = logging.getLogger(__name__)
 
 
+def parse_integer(request, name, default=None, required=False):
+    if name in request.args:
+        try:
+            return int(request.args[name][0])
+        except:
+            message = "Query parameter %r must be an integer" % (name,)
+            raise SynapseError(400, message)
+    else:
+        if required:
+            message = "Missing integer query parameter %r" % (name,)
+            raise SynapseError(400, message)
+        else:
+            return default
+
+
+def parse_boolean(request, name, default=None, required=False):
+    if name in request.args:
+        try:
+            return {
+                "true": True,
+                "false": False,
+            }[request.args[name][0]]
+        except:
+            message = (
+                "Boolean query parameter %r must be one of"
+                " ['true', 'false']"
+            ) % (name,)
+            raise SynapseError(400, message)
+    else:
+        if required:
+            message = "Missing boolean query parameter %r" % (name,)
+            raise SynapseError(400, message)
+        else:
+            return default
+
+
+def parse_string(request, name, default=None, required=False,
+                 allowed_values=None, param_type="string"):
+    if name in request.args:
+        value = request.args[name][0]
+        if allowed_values is not None and value not in allowed_values:
+            message = "Query parameter %r must be one of [%s]" % (
+                name, ", ".join(repr(v) for v in allowed_values)
+            )
+            raise SynapseError(message)
+        else:
+            return value
+    else:
+        if required:
+            message = "Missing %s query parameter %r" % (param_type, name)
+            raise SynapseError(400, message)
+        else:
+            return default
+
+
 class RestServlet(object):
 
     """ A Synapse REST Servlet.
@@ -56,58 +111,3 @@ class RestServlet(object):
                     http_server.register_path(method, pattern, method_handler)
         else:
             raise NotImplementedError("RestServlet must register something.")
-
-    @staticmethod
-    def parse_integer(request, name, default=None, required=False):
-        if name in request.args:
-            try:
-                return int(request.args[name][0])
-            except:
-                message = "Query parameter %r must be an integer" % (name,)
-                raise SynapseError(400, message)
-        else:
-            if required:
-                message = "Missing integer query parameter %r" % (name,)
-                raise SynapseError(400, message)
-            else:
-                return default
-
-    @staticmethod
-    def parse_boolean(request, name, default=None, required=False):
-        if name in request.args:
-            try:
-                return {
-                    "true": True,
-                    "false": False,
-                }[request.args[name][0]]
-            except:
-                message = (
-                    "Boolean query parameter %r must be one of"
-                    " ['true', 'false']"
-                ) % (name,)
-                raise SynapseError(400, message)
-        else:
-            if required:
-                message = "Missing boolean query parameter %r" % (name,)
-                raise SynapseError(400, message)
-            else:
-                return default
-
-    @staticmethod
-    def parse_string(request, name, default=None, required=False,
-                     allowed_values=None, param_type="string"):
-        if name in request.args:
-            value = request.args[name][0]
-            if allowed_values is not None and value not in allowed_values:
-                message = "Query parameter %r must be one of [%s]" % (
-                    name, ", ".join(repr(v) for v in allowed_values)
-                )
-                raise SynapseError(message)
-            else:
-                return value
-        else:
-            if required:
-                message = "Missing %s query parameter %r" % (param_type, name)
-                raise SynapseError(400, message)
-            else:
-                return default

synapse/rest/client/v2_alpha/sync.py

@@ -15,7 +15,9 @@
 
 from twisted.internet import defer
 
-from synapse.http.servlet import RestServlet
+from synapse.http.servlet import (
+    RestServlet, parse_string, parse_integer, parse_boolean
+)
 from synapse.handlers.sync import SyncConfig
 from synapse.types import StreamToken
 from synapse.events.utils import (
@@ -87,20 +89,20 @@ class SyncRestServlet(RestServlet):
     def on_GET(self, request):
         user, client = yield self.auth.get_user_by_req(request)
 
-        timeout = self.parse_integer(request, "timeout", default=0)
-        limit = self.parse_integer(request, "limit", required=True)
-        gap = self.parse_boolean(request, "gap", default=True)
-        sort = self.parse_string(
+        timeout = parse_integer(request, "timeout", default=0)
+        limit = parse_integer(request, "limit", required=True)
+        gap = parse_boolean(request, "gap", default=True)
+        sort = parse_string(
             request, "sort", default="timeline,asc",
             allowed_values=self.ALLOWED_SORT
         )
-        since = self.parse_string(request, "since")
-        set_presence = self.parse_string(
+        since = parse_string(request, "since")
+        set_presence = parse_string(
             request, "set_presence", default="online",
             allowed_values=self.ALLOWED_PRESENCE
         )
-        backfill = self.parse_boolean(request, "backfill", default=False)
-        filter_id = self.parse_string(request, "filter", default=None)
+        backfill = parse_boolean(request, "backfill", default=False)
+        filter_id = parse_string(request, "filter", default=None)
 
         logger.info(
             "/sync: user=%r, timeout=%r, limit=%r, gap=%r, sort=%r, since=%r,"

synapse/rest/media/v1/base_resource.py

@@ -18,7 +18,7 @@ from .thumbnailer import Thumbnailer
 from synapse.http.server import respond_with_json
 from synapse.util.stringutils import random_string
 from synapse.api.errors import (
-    cs_exception, CodeMessageException, cs_error, Codes, SynapseError
+    cs_error, Codes, SynapseError
 )
 
 from twisted.internet import defer
@@ -32,6 +32,18 @@ import logging
 logger = logging.getLogger(__name__)
 
 
+def parse_media_id(request):
+    try:
+        server_name, media_id = request.postpath
+        return (server_name, media_id)
+    except:
+        raise SynapseError(
+            404,
+            "Invalid media id token %r" % (request.postpath,),
+            Codes.UNKNOWN,
+        )
+
+
 class BaseMediaResource(Resource):
     isLeaf = True
 
@@ -47,72 +59,6 @@ class BaseMediaResource(Resource):
         self.filepaths = filepaths
         self.downloads = {}
 
-    @staticmethod
-    def catch_errors(request_handler):
-        @defer.inlineCallbacks
-        def wrapped_request_handler(self, request):
-            try:
-                yield request_handler(self, request)
-            except CodeMessageException as e:
-                logger.info("Responding with error: %r", e)
-                respond_with_json(
-                    request, e.code, cs_exception(e), send_cors=True
-                )
-            except:
-                logger.exception(
-                    "Failed handle request %s.%s on %r",
-                    request_handler.__module__,
-                    request_handler.__name__,
-                    self,
-                )
-                respond_with_json(
-                    request,
-                    500,
-                    {"error": "Internal server error"},
-                    send_cors=True
-                )
-        return wrapped_request_handler
-
-    @staticmethod
-    def _parse_media_id(request):
-        try:
-            server_name, media_id = request.postpath
-            return (server_name, media_id)
-        except:
-            raise SynapseError(
-                404,
-                "Invalid media id token %r" % (request.postpath,),
-                Codes.UNKNOWN,
-            )
-
-    @staticmethod
-    def _parse_integer(request, arg_name, default=None):
-        try:
-            if default is None:
-                return int(request.args[arg_name][0])
-            else:
-                return int(request.args.get(arg_name, [default])[0])
-        except:
-            raise SynapseError(
-                400,
-                "Missing integer argument %r" % (arg_name,),
-                Codes.UNKNOWN,
-            )
-
-    @staticmethod
-    def _parse_string(request, arg_name, default=None):
-        try:
-            if default is None:
-                return request.args[arg_name][0]
-            else:
-                return request.args.get(arg_name, [default])[0]
-        except:
-            raise SynapseError(
-                400,
-                "Missing string argument %r" % (arg_name,),
-                Codes.UNKNOWN,
-            )
-
     def _respond_404(self, request):
         respond_with_json(
             request, 404,

synapse/rest/media/v1/download_resource.py

@@ -13,7 +13,8 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from .base_resource import BaseMediaResource
+from .base_resource import BaseMediaResource, parse_media_id
+from synapse.http.server import request_handler
 
 from twisted.web.server import NOT_DONE_YET
 from twisted.internet import defer
@@ -28,15 +29,10 @@ class DownloadResource(BaseMediaResource):
         self._async_render_GET(request)
         return NOT_DONE_YET
 
-    @BaseMediaResource.catch_errors
+    @request_handler
     @defer.inlineCallbacks
     def _async_render_GET(self, request):
-        try:
-            server_name, media_id = request.postpath
-        except:
-            self._respond_404(request)
-            return
-
+        server_name, media_id = parse_media_id(request)
         if server_name == self.server_name:
             yield self._respond_local_file(request, media_id)
         else:

synapse/rest/media/v1/thumbnail_resource.py

@@ -14,7 +14,9 @@
 # limitations under the License.
 
 
-from .base_resource import BaseMediaResource
+from .base_resource import BaseMediaResource, parse_media_id
+from synapse.http.servlet import parse_string, parse_integer
+from synapse.http.server import request_handler
 
 from twisted.web.server import NOT_DONE_YET
 from twisted.internet import defer
@@ -31,14 +33,14 @@ class ThumbnailResource(BaseMediaResource):
         self._async_render_GET(request)
         return NOT_DONE_YET
 
-    @BaseMediaResource.catch_errors
+    @request_handler
     @defer.inlineCallbacks
     def _async_render_GET(self, request):
-        server_name, media_id = self._parse_media_id(request)
-        width = self._parse_integer(request, "width")
-        height = self._parse_integer(request, "height")
-        method = self._parse_string(request, "method", "scale")
-        m_type = self._parse_string(request, "type", "image/png")
+        server_name, media_id = parse_media_id(request)
+        width = parse_integer(request, "width")
+        height = parse_integer(request, "height")
+        method = parse_string(request, "method", "scale")
+        m_type = parse_string(request, "type", "image/png")
 
         if server_name == self.server_name:
             yield self._respond_local_thumbnail(

synapse/rest/media/v1/upload_resource.py

@@ -13,12 +13,10 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from synapse.http.server import respond_with_json
+from synapse.http.server import respond_with_json, request_handler
 
 from synapse.util.stringutils import random_string
-from synapse.api.errors import (
-    cs_exception, SynapseError, CodeMessageException
-)
+from synapse.api.errors import SynapseError
 
 from twisted.web.server import NOT_DONE_YET
 from twisted.internet import defer
@@ -69,9 +67,9 @@ class UploadResource(BaseMediaResource):
 
         defer.returnValue("mxc://%s/%s" % (self.server_name, media_id))
 
+    @request_handler
     @defer.inlineCallbacks
     def _async_render_POST(self, request):
-        try:
         auth_user, client = yield self.auth.get_user_by_req(request)
         # TODO: The checks here are a bit late. The content will have
         # already been uploaded to a tmp file at this point
@@ -108,14 +106,3 @@ class UploadResource(BaseMediaResource):
         respond_with_json(
             request, 200, {"content_uri": content_uri}, send_cors=True
         )
-        except CodeMessageException as e:
-            logger.exception(e)
-            respond_with_json(request, e.code, cs_exception(e), send_cors=True)
-        except:
-            logger.exception("Failed to store file")
-            respond_with_json(
-                request,
-                500,
-                {"error": "Internal server error"},
-                send_cors=True
-            )