Packer Variables

Purpose

• Make packer template generic
• This increases reusability

Packer Variable Types

• User Variables
• Environment Variables

Syntax for Creating Variables

{
    "variables": {
        "variable_name_1": "variable value"
    },
    "builders": [{

    }],
    "provisioners": [
        {

        }
    ]

}

Syntax for using variable

• User Variables: assume you have defined a user variable called as package

{{user `package`}}

• Environment Variables: assume you want to use PATH

{{env `PATH`}}

First Version of Pet-clinic

{
    "variables": {
        "aws_access_key": "",
        "aws_secret_key": "",
        "aws_region": "us-west-2",
        "aws_source_ami":  "ami-06f2f779464715dc5"      
    },
    "builders":[
        {
            "type": "amazon-ebs",
            "access_key": "{{user `aws_access_key`}}",
            "ami_name": "petclinic--{{isotime | clean_resource_name}}",
            "instance_type": "t2.micro",
            "region": "{{user `aws_region`}}",
            "secret_key": "{{user `aws_secret_key`}}",
            "source_ami": "{{user `aws_source_ami`}}",
            "ssh_username": "ubuntu"
        }
    ],
    "provisioners":[
        {
            "type": "shell",
            "script": "./deploypetclinic.sh"
        }
    ]
}

deploy petclinic.sh

#!/bin/bash
sudo apt-get update
sudo apt-get install openjdk-8-jdk -y
wget https://qt-s3-new-testing.s3-us-west-2.amazonaws.com/spring-petclinic.jar
echo "Spring petclinic is copied at /home/ubuntu/spring-petclinic.jar"

Commands to use

packer build -var 'aws_access_key=<youraccesskey>' -var 'aws_secret_key=<yoursecretkey> ./aws.json

Excercise:

1. Create a reusable packer template with tomcat installed
2. create a reusable packer template with nginx installed