From 52adf45740c1f9f914819482d358ca1fb755679c Mon Sep 17 00:00:00 2001
From: Julien Duponchelle <julien@gns3.net>
Date: Tue, 20 Dec 2016 09:15:28 +0100
Subject: [PATCH] Fix an error when docker hub failed to anwser

Fix #843
---
 gns3server/compute/docker/docker_vm.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/gns3server/compute/docker/docker_vm.py b/gns3server/compute/docker/docker_vm.py
index 8100344f..ccfbbaf8 100644
--- a/gns3server/compute/docker/docker_vm.py
+++ b/gns3server/compute/docker/docker_vm.py
@@ -268,6 +268,8 @@ class DockerVM(BaseNode):
             log.info("Image %s is missing pulling it from docker hub", self._image)
             yield from self.pull_image(self._image)
             image_infos = yield from self._get_image_information()
+            if image_infos is None:
+                raise DockerError("Can't get image informations, please try again.")
 
         params = {
             "Hostname": self._name,