Add syslog logging for varnish

Dockerfile

@@ -13,6 +13,9 @@ RUN chmod +x /start ;\
     rm /etc/varnish/secret
 
 ADD varnish.conf /etc/supervisor/conf.d/varnish.conf
+ADD varnishlogger.conf /etc/supervisor/conf.d/varnishlogger.conf
+ADD varnishlog.conf /etc/rsyslog.d/varnishlog.conf
+ADD rsyslogd.conf /etc/supervisor/conf.d/rsyslogd.conf
 ADD supervisor.conf /etc/supervisor/conf.d/supervisor.conf
 
 WORKDIR /etc/varnish

README.md

@@ -17,3 +17,5 @@ Container for running [Varnish Cache](https://www.varnish-cache.org/). Automatic
 *Extras*
 
 * test.vcl - example default.vcl file
+* monitorvcl - example showing how reload varnish when the vcl is modified
+* Apache-format logs are sent to the docker host with rsyslog with programname 'varnish', channel local6.notice

monitorvcl

@@ -0,0 +1,6 @@
+#!/bin/bash
+
+# Wait for the vcl to be modified then tell varnish to reload
+while inotifywait -qq --event modify /etc/varnish/default.vcl; do
+  pkill -HUP varnishd
+done

rsyslogd.conf

@@ -0,0 +1,2 @@
+[program:rsyslog]
+command=rsyslogd -n

start

@@ -3,18 +3,27 @@
 # Cleanly kill supervisor when container is stopped
 trap 'kill $(jobs -p)' EXIT
 
+# Set default varnish memory cache size if not specified
 if [ -z "$MEMSIZE" ]; then
     export MEMSIZE=64M
 fi
 
+# Set varnish secret if not specified
 if [ ! -f /etc/varnish/secret ]; then
     if [ -z "$SECRET" ]; then
         SECRET=`cat /proc/sys/kernel/random/uuid`
     fi
     echo $SECRET > /etc/varnish/secret
 fi
+echo "Secret is $SECRET"
 
-echo "Secret is `cat /etc/varnish/secret`"
+# Set access syslog host if not specified
+if [ -z "$LOGHOST" ]; then
+    LOGHOST=`ip route | grep default | awk '{print $3}'`
+fi
+sed -i -E "s/@.+/@$LOGHOST/" /etc/rsyslog.d/varnishlog.conf
+
+# Check vcl syntax
 varnishd -C -f /etc/varnish/default.vcl > /dev/null || exit 1
 
 supervisord

varnishlog.conf

@@ -0,0 +1,2 @@
+if $programname == 'varnish' then @172.17.42.1
+& ~

varnishlogger.conf

@@ -0,0 +1,5 @@
+[program:varnishlogger]
+command=bash -c "varnishncsa -F '%%{X-Real-IP}i %%l %%u %%t \"%%r\" %%s %%b \"%%{Referer}i\" \"%%{User-agent}i\"' | /usr/bin/logger -tvarnish -plocal6.notice"
+autostart=true
+autorestart=true
+redirect_stderr=true