From 8ab018fc17a32f697bad8145d1a05526889dd6b3 Mon Sep 17 00:00:00 2001
From: talwai <aaditya.21@gmail.com>
Date: Thu, 9 Jul 2015 10:40:58 -0400
Subject: [PATCH] [docker] catch error when parsing json response

---
 checks.d/docker.py | 31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/checks.d/docker.py b/checks.d/docker.py
index 8b24b9aab5..63bf20fdbb 100644
--- a/checks.d/docker.py
+++ b/checks.d/docker.py
@@ -65,6 +65,9 @@
 
 DEFAULT_SOCKET_TIMEOUT = 5
 
+class DockerJSONDecodeError(Exception):
+    """ Raised when there is trouble parsing the API response sent by Docker Remote API """
+    pass
 
 class UnixHTTPConnection(httplib.HTTPConnection):
     """Class used in conjuction with UnixSocketHandler to make urllib2
@@ -358,16 +361,21 @@ def _get_images(self, instance, with_size=True, get_all=False):
     def _get_events(self, instance):
         """Get the list of events """
         now = int(time.time())
-        result = self._get_json(
-            "%s/events" % instance["url"],
-            params={
-                "until": now,
-                "since": self._last_event_collection_ts[instance["url"]] or now - 60,
-            }, multi=True)
-        self._last_event_collection_ts[instance["url"]] = now
-        if type(result) == dict:
-            result = [result]
-        return result
+        try:
+            result = self._get_json(
+                "%s/events" % instance["url"],
+                params={
+                    "until": now,
+                    "since": self._last_event_collection_ts[instance["url"]] or now - 60,
+                },
+                multi=True
+            )
+            self._last_event_collection_ts[instance["url"]] = now
+            if type(result) == dict:
+                result = [result]
+            return result
+        except DockerJSONDecodeError:
+            return []
 
     def _get_json(self, uri, params=None, multi=False):
         """Utility method to get and parse JSON streams."""
@@ -396,8 +404,7 @@ def _get_json(self, uri, params=None, multi=False):
             return json.loads(response)
         except Exception as e:
             self.log.error('Failed to parse Docker API response: %s', response)
-            raise
-
+            raise DockerJSONDecodeError
 
     # Cgroups