Example Dockerfile for a Node.js member image

Use the Dockerfile example to create a Node.js collective member 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.

Dockerfile
joinMember script
removeMember script

Stabilized feature: Managing Node.js processes by using Liberty collectives is stabilized. V8 is the final supported Node.js version for Liberty collective members. For on-premises or bring-your-own infrastructure environments, use Docker containers that are hosted and managed by IBM Cloud® Private. For hosted environments, use Docker containers in IBM Cloud Kubernetes Service.

Dockerfile

Use the following Dockerfile example to create a Node.js collective member image. The image that is available on IBM Container Registry cannot access Network Deployment features such as scalingMember-1.0. You can use the last two lines to install an application onto the Docker image.

#
# Dockerfile to create a Node.js image
#
# This Dockerfile makes the following assumptions:
# - The collectives enabling scripts (joinMember, removeMember) will be placed in
#   /opt/ibm/docker in the Docker container
# - Node.js servers are created at /root/wlpn
# - The Node.js server will be "defaultServer" (for example, /root/wlpn/defaultServer)
# - The application to install will already have its dependencies resolved by "npm install"
# - The Docker container will be run using --net=host, so that no ports are explicitly exported in this file

FROM node:4-slim

#
# Auto-start the Node.js server with the container
#
ENTRYPOINT ["/usr/local/bin/wlpn-server", "run", "defaultServer"]

#
# Add collectives 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 OS and JRE
#
RUN apt-get update

#
# Install APIConnect collective member
#
RUN npm install -g apiconnect-collective-member


#
# Use the following code to install an application for use onto the Docker image
#
COPY express-example-app-1.0.2.tgz /root/wlpn/
RUN wlpn-server unpack defaultServer /root/wlpn/express-example-app-1.0.2.tgz

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 Node.js 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 - the hostname of the Docker host this container resides on
#
# Optional: --clusterName - cluster name for the member configuration. If specified, adds the cluster and scaling member features.
#


# 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. getops can be incorrect.
    
    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


    # Run the join operation

    if [[ $clusterName = *[!\ ]* ]]; then
        wlpn-collective join defaultServer --host=$controllerHost --port=$controllerPort --user=$controllerUser --password=$controllerPassword --keystorePassword=$memberKeystorePassword --autoAcceptCertificates --hostName=$dockerHost --clusterName=$clusterName --genDeployVars
    else
        echo "No clusterName provided. The container will not be configured as a cluster or scaling member."
        wlpn-collective join defaultServer --host=$controllerHost --port=$controllerPort --user=$controllerUser --password=$controllerPassword --keystorePassword=$memberKeystorePassword --autoAcceptCertificates --hostName=$dockerHost --genDeployVars 
    fi
else
    # At least one required parameter is missing. Provide 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

removeMember script

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

#!/bin/bash

# Script to remove a StrongLoop 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 - the hostname of the Docker host on which this container resides

# 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. getops can be incorrect.

    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

    wlpn-collective remove defaultServer --host=$controllerHost --port=$controllerPort --user=$controllerUser --password=$controllerPassword --hostName=$dockerHost --autoAcceptCertificates

else
    # At least one required parameter was missing. Provide 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