From f4697b5ec1071905b1177fd473e20df0b1455a4c Mon Sep 17 00:00:00 2001
From: Richard van der Hoff <1389908+richvdh@users.noreply.github.com>
Date: Thu, 24 Jan 2019 13:38:29 +0000
Subject: [PATCH] Fix UnboundLocalError in post_urlencoded_get_json (#4460)

This could cause exceptions if the id server returned 4xx responses.
---
 changelog.d/4460.bugfix | 1 +
 synapse/http/client.py  | 5 +++--
 2 files changed, 4 insertions(+), 2 deletions(-)
 create mode 100644 changelog.d/4460.bugfix

diff --git a/changelog.d/4460.bugfix b/changelog.d/4460.bugfix
new file mode 100644
index 0000000000..8c5d5b4e0e
--- /dev/null
+++ b/changelog.d/4460.bugfix
@@ -0,0 +1 @@
+Fix UnboundLocalError in post_urlencoded_get_json
diff --git a/synapse/http/client.py b/synapse/http/client.py
index afcf698b29..47a1f82ff0 100644
--- a/synapse/http/client.py
+++ b/synapse/http/client.py
@@ -333,9 +333,10 @@ class SimpleHttpClient(object):
             "POST", uri, headers=Headers(actual_headers), data=query_bytes
         )
 
+        body = yield make_deferred_yieldable(readBody(response))
+
         if 200 <= response.code < 300:
-            body = yield make_deferred_yieldable(treq.json_content(response))
-            defer.returnValue(body)
+            defer.returnValue(json.loads(body))
         else:
             raise HttpResponseException(response.code, response.phrase, body)