Add Elasticsearch cluster configuration (#146)

elasticsearch/Dockerfile

@@ -1,6 +1,8 @@
 # Wazuh App Copyright (C) 2019 Wazuh Inc. (License GPLv2)
 FROM docker.elastic.co/elasticsearch/elasticsearch:6.5.4
 
+ENV ELASTICSEARCH_URL="http://elasticsearch:9200"
+
 ENV ALERTS_SHARDS="1" \
     ALERTS_REPLICAS="0"
 
@@ -13,6 +15,20 @@ ENV ENABLE_CONFIGURE_S3="false"
 
 ENV TEMPLATE_VERSION=v3.8.2
 
+# Elasticearch cluster configuration environment variables
+# If ELASTIC_CLUSTER is set to "true" the following variables will be added to the Elasticsearch configuration
+ENV ELASTIC_CLUSTER="false" \
+    CLUSTER_NAME="wazuh" \
+    CLUSTER_NODE_MASTER="true" \
+    CLUSTER_NODE_DATA="true" \
+    CLUSTER_NODE_INGEST="true" \
+    CLUSTER_NODE_NAME="wazuh-elasticsearch" \
+    CLUSTER_MEMORY_LOCK="true" \
+    CLUSTER_DISCOVERY_SERVICE="wazuh-elasticsearch" \
+    CLUSTER_NUMBER_OF_MASTERS="2" \
+    CLUSTER_MAX_NODES="1" \
+    CLUSTER_DELAYED_TIMEOUT="1m"
+
 ADD https://raw.githubusercontent.com/wazuh/wazuh/$TEMPLATE_VERSION/extensions/elasticsearch/wazuh-elastic6-template-alerts.json /usr/share/elasticsearch/config
 
 COPY config/entrypoint.sh /entrypoint.sh
@@ -28,5 +44,8 @@ RUN elasticsearch-plugin install --batch repository-s3
 COPY config/configure_s3.sh ./config/configure_s3.sh
 RUN chmod 755 ./config/configure_s3.sh
 
+COPY --chown=elasticsearch:elasticsearch ./config/config_cluster.sh ./
+RUN chmod +x ./config_cluster.sh
+
 ENTRYPOINT ["/entrypoint.sh"]
 CMD ["elasticsearch"]