High: Introduces the docker agent to manage docker containers in an HA environment

doc/man/Makefile.am

@@ -98,6 +98,7 @@ man_MANS	       = ocf_heartbeat_AoEtarget.7 \
                           ocf_heartbeat_conntrackd.7 \
                           ocf_heartbeat_db2.7 \
                           ocf_heartbeat_dhcpd.7 \
+                          ocf_heartbeat_docker.7 \
                           ocf_heartbeat_eDir88.7 \
                           ocf_heartbeat_ethmonitor.7 \
                           ocf_heartbeat_exportfs.7 \

heartbeat/Makefile.am

@@ -67,6 +67,7 @@ ocf_SCRIPTS	     =  ClusterMon		\
 			dhcpd		\
 			Delay			\
 			dnsupdate		\
+			docker			\
 			eDir88			\
 			EvmsSCC			\
 			Evmsd			\

heartbeat/docker

@@ -0,0 +1,330 @@
+#!/bin/sh
+#
+# The docker HA resource agent creates and launches a docker container
+# based off a supplied docker image. Containers managed by this agent
+# are both created and removed upon the agent's start and stop actions.
+#
+# Copyright (c) 2014 David Vossel <dvossel@redhat.com>
+#                    All Rights Reserved.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of version 2 of the GNU General Public License as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it would be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+#
+# Further, this software is distributed without any warranty that it is
+# free of the rightful claim of any third person regarding infringement
+# or the like.  Any license provided herein, whether implied or
+# otherwise, applies only to this software file.  Patent licenses, if
+# any, provided herein do not apply to combinations of this program with
+# other software, or any other product whatsoever.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write the Free Software Foundation,
+# Inc., 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
+#
+
+#######################################################################
+# Initialization:
+
+: ${OCF_FUNCTIONS_DIR=${OCF_ROOT}/lib/heartbeat}
+. ${OCF_FUNCTIONS_DIR}/ocf-shellfuncs
+
+#######################################################################
+
+meta_data()
+{
+	cat <<END
+<?xml version="1.0"?>
+<!DOCTYPE resource-agent SYSTEM "ra-api-1.dtd">
+<resource-agent name="docker" version="0.9">
+<version>1.0</version>
+
+<longdesc lang="en">
+The docker HA resource agent creates and launches a docker container
+based off a supplied docker image. Containers managed by this agent
+are both created and removed upon the agent's start and stop actions.
+</longdesc>
+<shortdesc lang="en">Docker container resource agent.</shortdesc>
+
+<parameters>
+<parameter name="image" required="1" unique="0">
+<longdesc lang="en">
+The docker image to base this container off of.
+</longdesc>
+<shortdesc lang="en">docker image</shortdesc>
+<content type="string"/>
+</parameter>
+
+<parameter name="container" required="0" unique="0">
+<longdesc lang="en">
+The name to give the created container. By default this will 
+be that resource's instance name.
+</longdesc>
+<shortdesc lang="en">docker container name</shortdesc>
+<content type="string"/>
+</parameter>
+
+<parameter name="allow_pull" unique="0">
+<longdesc lang="en">
+Allow the image to be pulled from the configured docker registry when
+the image does not exist locally. NOTE, this can drastically increase
+the time required to start the container if the image repository is 
+pulled over the network.
+</longdesc>
+<shortdesc lang="en">Allow pulling non-local images</shortdesc>
+<content type="boolean"/>
+</parameter>
+
+<parameter name="run_opts" required="0" unique="0">
+<longdesc lang="en">
+Add options to be appended to the 'docker run' command which is used
+when creating the container during the start action. This option allows
+users to do things such as setting a custom entry point and injecting
+environment variables into the newly created container. Note the '-d' 
+option is supplied regardless of this value to force containers to run 
+in the background.
+</longdesc>
+<shortdesc lang="en">run options</shortdesc>
+<content type="string"/>
+</parameter>
+
+<parameter name="run_cmd" required="0" unique="0">
+<longdesc lang="en">
+Specifiy a command to launch within the container once 
+it has initialized.
+</longdesc>
+<shortdesc lang="en">run command</shortdesc>
+<content type="string"/>
+</parameter>
+
+<parameter name="force_kill" required="0" unique="0">
+<longdesc lang="en">
+Kill a container immediately rather than waiting for it to gracefully
+shutdown
+</longdesc>
+<shortdesc lang="en">force kill</shortdesc>
+<content type="boolean"/>
+</parameter>
+
+<parameter name="reuse" required="0" unique="0">
+<longdesc lang="en">
+Allow the container to be reused after stopping the container. By default
+containers are removed after stop. With the reuse option containers
+will persist after the container stops.
+</longdesc>
+<shortdesc lang="en">reuse container</shortdesc>
+<content type="boolean"/>
+</parameter>
+
+</parameters>
+
+<actions>
+<action name="start"        timeout="90" />
+<action name="stop"         timeout="90" />
+<action name="monitor"      timeout="30" interval="30" depth="0" />
+<action name="meta-data"    timeout="5" />
+<action name="validate-all"   timeout="30" />
+</actions>
+</resource-agent>
+END
+}
+
+#######################################################################
+REQUIRE_IMAGE_PULL=0
+
+docker_usage()
+{
+	cat <<END
+usage: $0 {start|stop|monitor|validate-all|meta-data}
+
+Expects to have a fully populated OCF RA-compliant environment set.
+END
+}
+
+container_exists()
+{
+	docker inspect $CONTAINER > /dev/null 2>&1
+}
+
+remove_container()
+{
+	if ocf_is_true "$OCF_RESKEY_reuse"; then
+		# never remove the container if we have reuse enabled.
+		return 0
+	fi
+
+	ocf_log notice "Cleaning up inactive container, ${CONTAINER}."
+	ocf_run docker rm $CONTAINER
+}
+
+docker_monitor()
+{
+	local val
+
+	container_exists
+	if [ $? -ne 0 ]; then
+		return $OCF_NOT_RUNNING
+	fi
+
+	# retrieve the 'Running' attribute for the container
+	val=$(docker inspect --format {{.State.Running}} $CONTAINER 2>/dev/null)
+	if [ $? -ne 0 ]; then
+		#not running as a result of container not being found
+		return $OCF_NOT_RUNNING
+	fi
+
+	if ocf_is_true "$val"; then
+		# container exists and is running
+		return $OCF_SUCCESS
+	fi
+
+	return $OCF_NOT_RUNNING
+}
+
+docker_start()
+{
+	local run_opts="-d --name=${CONTAINER}"
+	# check to see if the container has already started
+	docker_monitor
+	if [ $? -eq $OCF_SUCCESS ]; then
+		return $OCF_SUCCESS
+	fi
+
+	if [ -n "$OCF_RESKEY_run_opts" ]; then
+		run_opts="$run_opts $OCF_RESKEY_run_opts"
+	fi
+
+	if [ $REQUIRE_IMAGE_PULL -eq 1 ]; then
+		ocf_log notice "Beginning pull of image, ${OCF_RESKEY_image}"
+		docker pull "${OCF_RESKEY_image}"
+		if [ $? -ne 0 ]; then
+			ocf_exit_reason "failed to pull image ${OCF_RESKEY_image}"
+			return $OCF_ERR_GENERIC
+		fi
+	fi
+
+	if ocf_is_true "$OCF_RESKEY_reuse" && container_exists; then
+		ocf_log info "starting existing container $CONTAINER."
+		ocf_run docker start $CONTAINER
+	else 
+		ocf_log info "running container $CONTAINER for the first time"
+		ocf_run docker run $run_opts $OCF_RESKEY_image $OCF_RESKEY_run_cmd
+	fi
+
+	if [ $? -ne 0 ]; then
+		ocf_exit_reason "docker failed to launch container"
+		return $OCF_ERR_GENERIC
+	fi
+
+	docker_monitor
+	if [ $? -ne $OCF_SUCCESS ]; then
+		ocf_exit_reason "Newly created docker container exited after start"
+		return $OCF_ERR_GENERIC
+	fi
+
+	return $OCF_SUCCESS
+}
+
+docker_stop()
+{
+	local timeout=60
+	docker_monitor
+	if [ $? -eq  $OCF_NOT_RUNNING ]; then
+		return $OCF_SUCCESS
+	fi
+
+	if [ -n "$OCF_RESKEY_CRM_meta_timeout" ]; then
+		timeout=$((($OCF_RESKEY_CRM_meta_timeout/1000) -10 ))
+		if [ $timeout -lt 10 ]; then
+			timeout=10
+		fi
+	fi
+
+	if ocf_is_true "$OCF_RESKEY_force_kill"; then
+		ocf_run docker kill $CONTAINER
+	else 	
+		ocf_log debug "waiting $timeout second[s] before killing container"
+		ocf_run docker stop -t=$timeout $CONTAINER
+	fi
+
+	if [ $? -ne 0 ]; then
+		ocf_exit_reason "Failed to stop container, ${CONTAINER}, based on image, ${OCF_RESKEY_image}."
+		return $OCF_ERR_GENERIC
+	fi
+
+	remove_container
+	if [ $? -ne 0 ]; then
+		ocf_exit_reason "Failed to remove stopped container, ${CONTAINER}, based on image, ${OCF_RESKEY_image}."
+		return $OCF_ERR_GENERIC
+	fi
+
+	return $OCF_SUCCESS
+}
+
+image_exists()
+{
+	local res=1
+
+
+	echo "${OCF_RESKEY_image}" | grep -q ":"
+	if [ $? -eq 0 ]; then
+		docker images | awk '{print $1 ":" $2}' |  grep "^${OCF_RESKEY_image}\$" > /dev/null 2>&1
+	else
+		docker images | awk '{print $1}' | grep "^${OCF_RESKEY_image}\$" > /dev/null 2>&1
+	fi
+	if [ $? -eq 0 ]; then
+		return 0
+	fi
+	if ocf_is_true "$OCF_RESKEY_allow_pull"; then
+		REQUIRE_IMAGE_PULL=1
+		ocf_log notice "Image (${OCF_RESKEY_image}) does not exist locally but will be pulled during start"
+		return 0
+	fi 
+	# image not found.
+	return 1
+}
+
+docker_validate()
+{
+	check_binary docker
+	if [ -z "$OCF_RESKEY_image" ]; then
+		ocf_exit_reason "'image' option is required"
+		exit $OCF_ERR_CONFIGURED
+	fi 
+
+	image_exists
+	if [ $? -ne 0 ]; then
+		ocf_exit_reason "base image, ${OCF_RESKEY_image}, could not be found."
+		exit $OCF_ERR_CONFIGURED
+	fi
+
+	return $OCF_SUCCESS
+}
+
+: ${OCF_RESKEY_container=${OCF_RESOURCE_INSTANCE}}
+CONTAINER=$OCF_RESKEY_container
+
+case $__OCF_ACTION in
+meta-data) meta_data
+		exit $OCF_SUCCESS;;
+start)
+	docker_validate
+	docker_start;;
+stop)		docker_stop;;
+monitor)	docker_monitor;;
+validate-all)	docker_validate;;
+usage|help)	docker_usage
+		exit $OCF_SUCCESS
+		;;
+*)		docker_usage
+		exit $OCF_ERR_UNIMPLEMENTED
+		;;
+esac
+rc=$?
+ocf_log debug "${OCF_RESOURCE_INSTANCE} $__OCF_ACTION : $rc"
+exit $rc
+