Example Dockerfile for a Liberty Network Deployment image

Use the Dockerfile example to create a Liberty Network Deployment image. The Docker image has a joinMember script that joins the member server in the Docker container to a collective controller. The Docker image also has a removeMember script that removes the member server in the Docker container from the collective.

Stabilized feature: Managing Docker containers by using Liberty collectives is stabilized. For managing Docker containers, run your Liberty applications in IBM® Cloud Pak for Applications for on-premises or bring-your-own infrastructure. For hosted environments, use Docker containers in IBM Cloud® Kubernetes Service.

Dockerfile
joinMember script
removeMember script

Dockerfile

The following Dockerfile example can create a Liberty Network Deployment image. The image that is available on Docker hub cannot access Liberty Network Deployment features such as scalingMember-1.0. Use this file to create a Liberty Network Deployment image. You can use the last line to copy an application for use onto the Docker image.

# 
# Dockerfile to create a Liberty Network Deployment image
#
# This Dockerfile assumes:
# - The collective enabling scripts (joinMember, removeMember) will be placed in
#   /opt/ibm/docker in the Docker container
# - WebSphere Liberty will be installed at /opt/ibm/wlp
# - The WebSphere Liberty server will be "defaultServer"
#   (for example, /opt/ibm/wlp/usr/servers/defaultServer)
# - The Docker container runs using --net=host so that no ports are explicitly
#   exported in this file

FROM websphere-liberty

#
# Auto-start the Liberty server with the container
#
ENTRYPOINT ["/opt/ibm/wlp/bin/server", "run", "defaultServer"]
#
#

#
# Add collective enabling scripts
#
ADD joinMember /opt/ibm/docker/
RUN chmod +x /opt/ibm/docker/joinMember
ADD removeMember /opt/ibm/docker/
RUN chmod +x /opt/ibm/docker/removeMember

#
# Update the operating system 
#
RUN apt-get update

#
# Add the additional required features
#
RUN installUtility install --acceptLicense scalingMember-1.0 clusterMember-1.0
collectiveMember-1.0

ADD server.xml /opt/ibm/wlp/usr/servers/defaultServer/

#
# Insert your application file name. This statement copies the application
# onto the Docker image.
# 
ADD application_file /opt/ibm/wlp/usr/servers/defaultServer/dropins/

joinMember script

The Docker image joinMember script joins the member server in the Docker container to a collective controller:

#!/bin/bash

#
# Script to join a Liberty Docker container to a collective controller.
#
# Required: <containerName> - positional parameter that is the name 
#                             of this Docker container
#           --host - collective controller hostname
#           --port - collective controller https port
#           --user - collective controller admin user
#           --password - collective controller admin user password
#           --keystorePassword - to be used for the member keystore
#           --dockerHost - hostname of the Docker host this container resides on
#
# Optional: --clusterName - cluster name for the member configuration.  
#                           If specified, it adds the cluster and scaling 
#                           member features also.
#

# Set initial values

containerName=$1

# Parse the command line

failure="false"

if [[ -z $1 ]]; then
    # No values received
    echo "Error: no parameters specified"
    failure="true"
else
    TEMP=`getopt --long host:,port:,user:,password:,keystorePassword:,dockerHost:,clusterName:: -- "$@"`
    eval set -- "$TEMP"
    OPTIND=-1
    
    while true ; do
        case "$1" in
           --host) controllerHost=$2; shift 2;;
           --port) controllerPort=$2; shift 2;;
           --user) controllerUser=$2; shift 2;;
           --password) controllerPassword=$2; shift 2;;
           --keystorePassword) memberKeystorePassword=$2; shift 2;;
           --dockerHost) dockerHost=$2; shift 2;;
           --clusterName) clusterName=$2; shift 2;;
           *) break;;
        esac
    done

    # Validate the required parameters
    if [[ -z "$containerName" ]]; then
        echo "Error: no containerName specified, validation suspended"
        failure="true"
    fi

    # if a containerName is not specified, bash uses the 
    # 1st "--" parameter as the containerName

    if [[ $containerName == --* ]]; then
        echo "Error: no containerName specified, validation suspended"
        failure="true"
    fi
    
    # When the positional parameter containerName fails, 
    # suspend validation reporting
    
    if [[ $failure == false ]]; then
        if [[ -z "${controllerHost// }" ]]; then
            echo "Error: no host specified"
            failure="true"
        fi
        if [[ -z "${controllerPort// }" ]]; then
            echo "Error: no port specified"
            failure="true"
        fi
        if [[ -z "${controllerUser// }" ]]; then
            echo "Error: no user specified"
            failure="true"
        fi
        if [[ -z "${controllerPassword// }" ]]; then
            echo "Error: no password specified"
            failure="true"
        fi
        if [[ -z "${memberKeystorePassword// }" ]]; then
            echo "Error: no keystorePassword specified"
            failure="true"
        fi
        if [[ -z "${dockerHost// }" ]]; then
            echo "Error: no dockerHost specified"
            failure="true"
        fi
    fi
fi

if [[ $failure == false ]]; then
    # Create the env.properties file for the Liberty Docker member

    echo containerName=$containerName > /opt/ibm/docker/env.properties
    echo containerHost=$dockerHost >> /opt/ibm/docker/env.properties


    # Invoke the collective utility

    /opt/ibm/wlp/bin/collective join defaultServer --host=$controllerHost --port=$controllerPort --user=$controllerUser --password=$controllerPassword --hostName=$dockerHost --createConfigFile --keystorePassword=$memberKeystorePassword --autoAcceptCertificates --genDeployVariables

    # Save join return code    
    joinRC=$?

    # Build additional config dropin snippets

    if [[ $clusterName = *[!\ ]* ]]; then
        echo \<?xml version=\"1.0\" encoding=\"UTF-8\" ?\> > /opt/ibm/wlp/usr/servers/defaultServer/cfgfeatures.xml
        echo \<server\> >> /opt/ibm/wlp/usr/servers/defaultServer/cfgfeatures.xml
        echo $'\t'\<featureManager\> >> /opt/ibm/wlp/usr/servers/defaultServer/cfgfeatures.xml
        echo $'\t'$'\t'\<feature\>clusterMember-1.0\</feature\> >>  /opt/ibm/wlp/usr/servers/defaultServer/cfgfeatures.xml
        echo $'\t'$'\t'\<feature\>scalingMember-1.0\</feature\> >>  /opt/ibm/wlp/usr/servers/defaultServer/cfgfeatures.xml
        echo $'\t'\</featureManager\> >> /opt/ibm/wlp/usr/servers/defaultServer/cfgfeatures.xml
        echo \</server\> >> /opt/ibm/wlp/usr/servers/defaultServer/cfgfeatures.xml
        echo \<?xml version=\"1.0\" encoding=\"UTF-8\" ?\> > /opt/ibm/wlp/usr/servers/defaultServer/cluster-config.xml
        echo \<server\> >> /opt/ibm/wlp/usr/servers/defaultServer/cluster-config.xml
        echo $'\t'\<clusterMember name=\"$clusterName\" /\> >> /opt/ibm/wlp/usr/servers/defaultServer/cluster-config.xml
        echo \</server\> >> /opt/ibm/wlp/usr/servers/defaultServer/cluster-config.xml
    else
        echo "No clusterName provided, the container will not be configured as a cluster or scaling member."
    fi


    # Move config snippets to the proper location for consumption

    mkdir -p /opt/ibm/wlp/usr/servers/defaultServer/configDropins/overrides
    mv /opt/ibm/wlp/usr/servers/defaultServer/c*.xml /opt/ibm/wlp/usr/servers/defaultServer/configDropins/overrides
    if [ -f /opt/ibm/wlp/usr/servers/defaultServer/user-collective-include.xml ]
    then
        cp /opt/ibm/wlp/usr/servers/defaultServer/user-collective-include.xml /opt/ibm/wlp/usr/servers/defaultServer/configDropins/overrides
    fi
else
    # At least one required parameter was missing, 
    # notify the user of the correct syntax
    printf "Usage:  joinMember <containerName> \n\t--host <controller host> \n\t--port <controller https port> \n\t--user <controller user> \n\t--password <controller password> \n\t--keystorePassword <member keystore password> \n\t--dockerHost <hostname of the Docker host> \n\t[--clusterName <cluster name for the member>]\n"
fi

exit $joinRC

removeMember script

The Docker image removeMember script removes the member server in the Docker container from the collective:

#!/bin/bash

# Script to remove a Liberty Docker container from a collective controller.
#
# Required: <containerName> - positional parameter that is the
#                             name of this Docker container
#           --host - collective controller hostname
#           --port - collective controller https port
#           --user - collective controller admin user
#           --password - collective controller admin user password
#           --dockerHost - hostname of the Docker host this container resides on
#
#

# Set initial values

containerName=$1

# Parse the command line

failure="false"

if [[ -z $1 ]]; then
    # No values received
    echo "Error: no parameters specified"
    failure="true"
else
    TEMP=`getopt --long host:,port:,user:,password:,dockerHost:: -- "$@"`
    eval set -- "$TEMP"
    OPTIND=-1

    while true ; do
        case "$1" in
           --host) controllerHost=$2; shift 2;;
           --port) controllerPort=$2; shift 2;;
           --user) controllerUser=$2; shift 2;;
           --password) controllerPassword=$2; shift 2;;
           --dockerHost) dockerHost=$2; shift 2;;
           *) break;;
        esac
    done

    # Validate the required parameters
    if [[ -z "$containerName" ]]; then
        echo "Error: no containerName specified, validation suspended"
        failure="true"
    fi

    # if a containerName is not specified, bash uses the
    # 1st "--" parameter as the containerName

    if [[ $containerName == --* ]]; then
        echo "Error: no containerName specified, validation suspended"
        failure="true"
    fi

    # When the positional parameter containerName fails, 
    # suspend validation reporting

    if [[ $failure == false ]]; then
        if [[ -z "${controllerHost// }" ]]; then
            echo "Error: no host specified"
            failure="true"
        fi
        if [[ -z "${controllerPort// }" ]]; then
            echo "Error: no port specified"
            failure="true"
        fi
        if [[ -z "${controllerUser// }" ]]; then
            echo "Error: no user specified"
            failure="true"
        fi
        if [[ -z "${controllerPassword// }" ]]; then
            echo "Error: no password specified"
            failure="true"
        fi
        if [[ -z "${dockerHost// }" ]]; then
            echo "Error: no dockerHost specified"
            failure="true"
        fi
    fi
fi

    # Invoke the collective utility
if [[ $failure == false ]]; then

    /opt/ibm/wlp/bin/collective remove defaultServer --host=$controllerHost --port=$controllerPort --user=$controllerUser --password=$controllerPassword  --hostName=$dockerHost --autoAcceptCertificates

else
    # At least one required parameter was missing, 
    # notify the user of the correct syntax
    printf "Usage:  removeMember <containerName> \n\t--host=<controller host> \n\t--port=<controller https port> \n\t--user=<controller user> \n\t--password=<controller password> \n\t--dockerHost=<docker host> \n"
fi