Docker – How to Create Javascript Runtime using NodeJS

• Install NodeJS Runtime with Docker Container
• Script to Create NodeJS Container
• Test JS script execution

Install NodeJS Runtime with Docker Container

Following code could be used to build the NodeJS image:

# Use centos6 base image
FROM    centos:centos6

# Enable Extra Packages for Enterprise Linux (EPEL) for CentOS
RUN     yum install -y epel-release

# Install Node.js and npm
RUN     yum install -y nodejs npm

Script to Create NodeJS Container

Following script (name it as installNode.js) could be used to create NodeJS container:

#!/bin/sh

if [ $# == 0 ]; then
  echo "This script expect container name argument. Example: ./installNode.sh node1"
  exit 100
fi

# Build NodeJS image if it does not exists
#
nb_image="nodejs_base"
nb_df="nodejs_base.df"
if [ `docker images $nb_image | wc -l` -lt 2 ]; then
  echo "Docker Image $nb_image do not exist..."
  echo "Builing docker image $nb_image"
  if [ -f $nb_df ]; then
    docker build -t $nb_image -f $nb_df .
  else
    echo "Can't find Dockerfile $nb_df in the current location"
    exit 200
  fi
fi

docker run -ti -dP --name $1 -v /c/Users:/mnt/Users $nb_image /bin/bash

Execute the above script using following code to start the container with name as “node1”

./installNode.js node1

Test JS File Execution

Login inside the NodeJS container with following code:

docker exec -ti node1 bash

Once logged in, create a sample file, namely hello.js, such as following:

function hello(user) {
    return "Hello, " + user;
}

console.log(hello("Calvin"));

Execute using Node runtime in following way and “Hello, Calvin” will be printed.

node hello.js