From bc79a9187f0eb97af68e2af955e31776eb321d58 Mon Sep 17 00:00:00 2001
From: Bryan Boreham <bjboreham@gmail.com>
Date: Thu, 12 May 2016 15:38:08 +0000
Subject: [PATCH] Protect against Docker hanging trying to talk to a
 non-existent plugin

Remove the Unix socket from the filesystem before doing volume
operations, if the plugin is not running.
---
 weave | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/weave b/weave
index 6ebd4efc..0b75b380 100755
--- a/weave
+++ b/weave
@@ -1740,6 +1740,7 @@ launch_router() {
 
     # Create a data-only container for persistence data
     if ! docker inspect -f ' ' $DB_CONTAINER_NAME > /dev/null 2>&1 ; then
+       protect_against_docker_hang
        docker create -v /weavedb --name=$DB_CONTAINER_NAME \
            --label=weavevolumes $WEAVEDB_IMAGE >/dev/null
     fi
@@ -1803,6 +1804,7 @@ launch_proxy() {
     mkdir -p /var/run/weave
     # Create a data-only container to mount the weavewait files from
     if ! docker inspect -f ' ' $VOLUMES_CONTAINER_NAME > /dev/null 2>&1 ; then
+       protect_against_docker_hang
        docker create -v /w -v /w-noop -v /w-nomcast --name=$VOLUMES_CONTAINER_NAME \
            --label=weavevolumes --entrypoint=/bin/false $EXEC_IMAGE >/dev/null
     fi
@@ -1864,6 +1866,13 @@ stop_plugin() {
     stop $PLUGIN_CONTAINER_NAME "Plugin"
 }
 
+protect_against_docker_hang() {
+    # If the plugin is not running, remove its socket so Docker doesn't try to talk to it
+    if !check_running $PLUGIN_CONTAINER_NAME 2>/dev/null ; then
+        rm -f /run/docker/plugins/weave.sock /run/docker/plugins/weavemesh.sock
+    fi
+}
+
 ##########################################################################################
 
 [ $(id -u) = 0 ] || {