From af4a1bac5088e8083f55eea05f6fad44208a3a51 Mon Sep 17 00:00:00 2001
From: Kegan Dougal <kegan@matrix.org>
Date: Mon, 14 Nov 2016 09:52:41 +0000
Subject: [PATCH] Move .observe() up to the cache to make things neater

---
 synapse/rest/client/transactions.py          |  9 +++---
 synapse/rest/client/v1/room.py               | 30 ++++----------------
 synapse/rest/client/v2_alpha/sendtodevice.py |  5 +---
 3 files changed, 11 insertions(+), 33 deletions(-)

diff --git a/synapse/rest/client/transactions.py b/synapse/rest/client/transactions.py
index 1db972a378..8d69e12d36 100644
--- a/synapse/rest/client/transactions.py
+++ b/synapse/rest/client/transactions.py
@@ -67,19 +67,18 @@ class HttpTransactionCache(object):
             txn_key (str): A key to ensure idempotency should fetch_or_execute be
             called again at a later point in time.
             fn (function): A function which returns a tuple of
-            (response_code, response_dict)d
+            (response_code, response_dict).
             *args: Arguments to pass to fn.
             **kwargs: Keyword arguments to pass to fn.
         Returns:
-            synapse.util.async.ObservableDeferred which resolves to a tuple
-            of (response_code, response_dict).
+            Deferred which resolves to a tuple of (response_code, response_dict).
         """
         try:
-            return self.transactions[txn_key]
+            return self.transactions[txn_key].observe()
         except KeyError:
             pass  # execute the function instead.
 
         deferred = fn(*args, **kwargs)
         observable = ObservableDeferred(deferred)
         self.transactions[txn_key] = observable
-        return observable
+        return observable.observe()
diff --git a/synapse/rest/client/v1/room.py b/synapse/rest/client/v1/room.py
index 0622e64380..3fb1f2deb3 100644
--- a/synapse/rest/client/v1/room.py
+++ b/synapse/rest/client/v1/room.py
@@ -53,13 +53,10 @@ class RoomCreateRestServlet(ClientV1RestServlet):
                                    client_path_patterns("/createRoom(?:/.*)?$"),
                                    self.on_OPTIONS)
 
-    @defer.inlineCallbacks
     def on_PUT(self, request, txn_id):
-        observable = self.txns.fetch_or_execute_request(
+        return self.txns.fetch_or_execute_request(
             request, self.on_POST, request
         )
-        res = yield observable.observe()
-        defer.returnValue(res)
 
     @defer.inlineCallbacks
     def on_POST(self, request):
@@ -208,13 +205,10 @@ class RoomSendEventRestServlet(ClientV1RestServlet):
     def on_GET(self, request, room_id, event_type, txn_id):
         return (200, "Not implemented")
 
-    @defer.inlineCallbacks
     def on_PUT(self, request, room_id, event_type, txn_id):
-        observable = self.txns.fetch_or_execute_request(
+        return self.txns.fetch_or_execute_request(
             request, self.on_POST, request, room_id, event_type, txn_id
         )
-        res = yield observable.observe()
-        defer.returnValue(res)
 
 
 # TODO: Needs unit testing for room ID + alias joins
@@ -271,13 +265,10 @@ class JoinRoomAliasServlet(ClientV1RestServlet):
 
         defer.returnValue((200, {"room_id": room_id}))
 
-    @defer.inlineCallbacks
     def on_PUT(self, request, room_identifier, txn_id):
-        observable = self.txns.fetch_or_execute_request(
+        return self.txns.fetch_or_execute_request(
             request, self.on_POST, request, room_identifier, txn_id
         )
-        res = yield observable.observe()
-        defer.returnValue(res)
 
 
 # TODO: Needs unit testing
@@ -519,13 +510,10 @@ class RoomForgetRestServlet(ClientV1RestServlet):
 
         defer.returnValue((200, {}))
 
-    @defer.inlineCallbacks
     def on_PUT(self, request, room_id, txn_id):
-        observable = self.txns.fetch_or_execute_request(
+        return self.txns.fetch_or_execute_request(
             request, self.on_POST, request, room_id, txn_id
         )
-        res = yield observable.observe()
-        defer.returnValue(res)
 
 
 # TODO: Needs unit testing
@@ -597,13 +585,10 @@ class RoomMembershipRestServlet(ClientV1RestServlet):
                 return False
         return True
 
-    @defer.inlineCallbacks
     def on_PUT(self, request, room_id, membership_action, txn_id):
-        observable = self.txns.fetch_or_execute_request(
+        return self.txns.fetch_or_execute_request(
             request, self.on_POST, request, room_id, membership_action, txn_id
         )
-        res = yield observable.observe()
-        defer.returnValue(res)
 
 
 class RoomRedactEventRestServlet(ClientV1RestServlet):
@@ -635,13 +620,10 @@ class RoomRedactEventRestServlet(ClientV1RestServlet):
 
         defer.returnValue((200, {"event_id": event.event_id}))
 
-    @defer.inlineCallbacks
     def on_PUT(self, request, room_id, event_id, txn_id):
-        observable = self.txns.fetch_or_execute_request(
+        return self.txns.fetch_or_execute_request(
             request, self.on_POST, request, room_id, event_id, txn_id
         )
-        res = yield observable.observe()
-        defer.returnValue(res)
 
 
 class RoomTypingRestServlet(ClientV1RestServlet):
diff --git a/synapse/rest/client/v2_alpha/sendtodevice.py b/synapse/rest/client/v2_alpha/sendtodevice.py
index 2ce038c6cd..2187350d42 100644
--- a/synapse/rest/client/v2_alpha/sendtodevice.py
+++ b/synapse/rest/client/v2_alpha/sendtodevice.py
@@ -43,13 +43,10 @@ class SendToDeviceRestServlet(servlet.RestServlet):
         self.txns = HttpTransactionCache()
         self.device_message_handler = hs.get_device_message_handler()
 
-    @defer.inlineCallbacks
     def on_PUT(self, request, message_type, txn_id):
-        observable = self.txns.fetch_or_execute_request(
+        return self.txns.fetch_or_execute_request(
             request, self._put, request, message_type, txn_id
         )
-        res = yield observable.observe()
-        defer.returnValue(res)
 
     @defer.inlineCallbacks
     def _put(self, request, message_type, txn_id):