Add an entrypoint file for docker image

Author: johanlelan

docker-entrypoint.sh

@@ -0,0 +1,21 @@
+#!/bin/sh
+
+set -eux
+
+# Drop root privileges if we are running catalina
+# allow the container to be started with `--user`
+
+if [ "$1" = 'catalina' -a "$(id -u)" = '0' ]; then
+
+	# Change the ownership to tomcat
+	chown -R tomcat:tomcat ${CATALINA_HOME}/* && chown -R tomcat:tomcat /data
+	shift
+	exec su-exec tomcat /opt/tomcat/bin/catalina.sh "$@"
+else
+
+	# As argument is not related to catalina,
+	# then assume that user wants to run his own process,
+	# for example a `bash` shell to explore this image
+	exec "$@"
+
+fi