Add a variable to provide a list of masters and update readme

Dockerfile

@@ -13,13 +13,14 @@ RUN arch="$(dpkg --print-architecture)" \
 # add our user and group first to make sure their IDs get assigned consistently, regardless of whatever dependencies get added
 RUN groupadd -r curator && useradd -r -g curator curator
 
-RUN pip install elasticsearch-curator==3.4.0
+RUN pip install elasticsearch-curator==3.5.1
 
 COPY docker-entrypoint.sh /
 
 ENV INTERVAL_IN_HOURS=24
 ENV OLDER_THAN_IN_DAYS="20"
 ENV ELASTICSEARCH_HOST=elasticsearch
+ENV ELASTICSEARCH_PORT=9200
 
 ENTRYPOINT ["/docker-entrypoint.sh"]
 

docker-entrypoint.sh

@@ -7,12 +7,28 @@ if [ "${1:0:1}" = '-' ]; then
 	set -- curator "$@"
 fi
 
+## Find out who is the master
+if [[ ${ELASTICSEARCH_MASTERS} ]]
+then
+  echo "Finding elasticsearch master from: $ELASTICSEARCH_MASTERS"
+  for master in ${ELASTICSEARCH_MASTERS//,/ }
+  do
+    response=$(wget -qO- http://${master}:9200/_cat/master)
+    if [ "$?" -eq 0 ]
+    then
+      ELASTICSEARCH_HOST=$(echo $response | awk '{printf $NF}')
+      echo "Master found: $ELASTICSEARCH_HOST"
+      break
+    fi
+  done
+fi
+
 # Step down via gosu  
 if [ "$1" = 'curator' ]; then
-	exec gosu curator bash -c "while true; do curator --host $ELASTICSEARCH_HOST delete indices --older-than $OLDER_THAN_IN_DAYS --time-unit=days --timestring '%Y.%m.%d'; set -e; sleep $(( 60*60*INTERVAL_IN_HOURS )); set +e; done"
+	exec gosu curator bash -c "while true; do curator --host $ELASTICSEARCH_HOST --port $ELASTICSEARCH_PORT delete indices --older-than $OLDER_THAN_IN_DAYS --time-unit=days --timestring '%Y.%m.%d'; set -e; sleep $(( 60*60*INTERVAL_IN_HOURS )); set +e; done"
 fi
 
 # As argument is not related to curator,
 # then assume that user wants to run his own process,
 # for example a `bash` shell to explore this image
-exec "$@"
+exec "$@"

readme.md

@@ -4,10 +4,11 @@ This only job executed by the docker built from this repository is to clean the
 
 It can be run as follows:
 
-	docker run -d -e INTERVAL_IN_HOURS=24 -e OLDER_THAN_IN_DAYS="10" --link es1:elasticsearch visity/elasticsearch-curator
+	docker run -d -e INTERVAL_IN_HOURS=24 -e OLDER_THAN_IN_DAYS="10" -e ELASTICSEARCH_HOST="localhost" visity/elasticsearch-curator
 
-where **es1** is the name of the elasticsearch container and
-
 * **INTERVAL\_IN\_HOURS**: The amount of time between two curator runs
 * **OLDER\_THAN\_IN\_DAYS**: Indicates all logs with a date exceeding this age can be deleted.
+* **ELASTICSEARCH\_HOST**: Points to the elasticsearch master url
+* **ELASTICSEARCH\_MASTERS**: Optionally, other than ELASTICSEARCH\_HOST, a list of hosts can be provided here and the master will be chosen amongst them
+* **ELASTICSEARCH\_PORT**: Port to access elasticsearch. It defaults to 9200