clean up pidfiles to sort out issue #8

Author: spujadas

Dockerfile

@@ -41,8 +41,8 @@ RUN mkdir ${LOGSTASH_HOME} \
  && rm -f ${LOGSTASH_PACKAGE} \
  && groupadd -r logstash \
  && useradd -r -s /usr/sbin/nologin -d ${LOGSTASH_HOME} -c "Logstash service user" -g logstash logstash \
- && chown -R logstash:logstash ${LOGSTASH_HOME} \
- && mkdir -p /var/log/logstash /etc/logstash/conf.d
+ && mkdir -p /var/log/logstash /etc/logstash/conf.d \
+ && chown -R logstash:logstash ${LOGSTASH_HOME} /var/log/logstash
 
 ADD ./logstash-init /etc/init.d/logstash
 RUN sed -i -e 's#^LS_HOME=$#LS_HOME='$LOGSTASH_HOME'#' /etc/init.d/logstash \

logstash-init

@@ -88,6 +88,7 @@ stop() {
       echo "$name stop failed; still running."
     else
       echo "$name stopped."
+      rm -f $pidfile
     fi
   fi
 }
@@ -114,6 +115,7 @@ force_stop() {
   if status; then
     stop
     status && kill -KILL $(cat "$pidfile")
+    rm -f $pidfile
   fi
 }
 

start.sh

@@ -3,11 +3,43 @@
 # /usr/local/bin/start.sh
 # Start Elasticsearch, Logstash and Kibana services
 #
+# spujadas 2015-10-09; added initial pidfile removal and graceful termination
+
+# WARNING - This script assumes that the ELK services are not running, and is
+#   only expected to be run once, when the container is started.
+#   Do not attempt to run this script if the ELK services are running (or be
+#   prepared to reap zombie processes).
+
+
+## handle termination gracefully
+
+_term() {
+  echo "Terminating ELK"
+  service elasticsearch stop
+  service logstash stop
+  service kibana stop
+  exit 0
+}
+
+trap _term SIGTERM
+
+
+## remove pidfiles in case previous graceful termination failed
+# NOTE - This is the reason for the WARNING at the top - it's a bit hackish, 
+#   but if it's good enough for Fedora (https://goo.gl/88eyXJ), it's good
+#   enough for me :)
+
+rm -f /var/run/elasticsearch/elasticsearch.pid /var/run/logstash.pid \
+  /var/run/kibana4.pid
+
+
+## start services
 
 service elasticsearch start
 service logstash start
 
-# wait for elasticsearch to start up - https://github.com/elasticsearch/kibana/issues/3077
+# wait for elasticsearch to start up
+# - https://github.com/elasticsearch/kibana/issues/3077
 counter=0
 while [ ! "$(curl localhost:9200 2> /dev/null)" -a $counter -lt 30  ]; do
   sleep 1
@@ -17,4 +49,5 @@ done
 
 service kibana start
 
-tail -f /var/log/elasticsearch/elasticsearch.log
+tail -f /var/log/elasticsearch/elasticsearch.log &
+wait