README.md

   1 Docker-Ansible base images
   2 ===================
   3
   4 [![Build Status](https://travis-ci.org/William-Yeh/docker-ansible.svg?branch=master)](https://travis-ci.org/William-Yeh/docker-ansible)
   5
   6
   7 ## Summary
   8
   9 Repository name in Docker Hub: **[williamyeh/ansible](https://registry.hub.docker.com/u/williamyeh/ansible/)**
  10
  11 This repository contains Dockerized [Ansible](https://github.com/ansible/ansible), published to the public [Docker Hub](https://registry.hub.docker.com/) via **automated build** mechanism.
  12
  13
  14
  15 ## Configuration
  16
  17 These are Docker images for [Ansible](https://github.com/ansible/ansible) software, installed in a selected Linux distributions.
  18
  19 - OS: Debian (jessie, wheezy), Ubuntu (trusty, precise), CentOS (7, 6)
  20
  21 - Ansible: usually the latest version.
  22
  23
  24 ## Images and tags
  25
  26 - normal series:
  27
  28   - `williamyeh/ansible:debian8`
  29   - `williamyeh/ansible:debian7`
  30   - `williamyeh/ansible:ubuntu14.04`
  31   - `williamyeh/ansible:ubuntu12.04`
  32   - `williamyeh/ansible:centos7`
  33   - `williamyeh/ansible:centos6`
  34
  35 - onbuild series:
  36
  37   - `williamyeh/ansible:debian8-onbuild`
  38   - `williamyeh/ansible:debian7-onbuild`
  39   - `williamyeh/ansible:ubuntu14.04-onbuild`
  40   - `williamyeh/ansible:ubuntu12.04-onbuild`
  41   - `williamyeh/ansible:centos7-onbuild`
  42   - `williamyeh/ansible:centos6-onbuild`
  43
  44
  45 ## Why yet another Ansible image for Docker?
  46
  47 There has been quite a few Ansible images for Docker (e.g., [search](https://registry.hub.docker.com/search?q=ansible) in the Docker Hub), so why reinvent the wheel?
  48
  49 In the beginning I used the [`ansible/ansible-docker-base`](https://github.com/ansible/ansible-docker-base) created by Ansible Inc. It worked well, but left some room for improvement:
  50
  51 - *Base OS image* - It provides only `centos:centos7` and `ubuntu:14.04`.  Insufficent for me.
  52
  53 - *Unnecessary dependencies* - It installed, at the very beginning of its Dockerfile, the `software-properties-common` package, which in turns installed some Python packages. I prefered to incorporate these stuff only when absolutely needed.
  54
  55 Therefore, I built these Docker images on my own.
  56
  57
  58 ## Usage
  59
  60 Used mostly as a *base image* for configuring, with Ansible, other software stack on some specified Linux distribution.
  61
  62 Take Debian/Ubuntu for example. To test an Ansible `playbook.yml` against a variety of Linux distributions, we may use [Vagrant](https://www.vagrantup.com/) as follows:
  63
  64 ```ruby
  65 # Vagrantfile
  66
  67 Vagrant.configure(2) do |config|
  68
  69     # ==> Choose a Vagrant box to emulate Linux distribution...
  70     config.vm.box = "ubuntu/trusty64"
  71     #config.vm.box = "hashicorp/precise64"
  72     #config.vm.box = "chef/debian-7.8"
  73     #config.vm.box = "chef/centos-7.0"
  74     #config.vm.box = "chef/centos-6.6"
  75
  76
  77     # ==> Executing Ansible...
  78     config.vm.provision "ansible" do |ansible|
  79         ansible.playbook = "playbook.yml"
  80     end
  81
  82 end
  83 ```
  84
  85 Virtual machines can emulate a variety of Linux distributions with good quality, at the cost of runtime overhead.
  86
  87
  88 Docker to be a rescue. Now, with these **williamyeh/ansible** series, we may test an Ansible `playbook.yml` against a variety of Linux distributions as follows:
  89
  90
  91 ```dockerfile
  92 # Dockerfile
  93
  94 # ==> Choose a base image to emulate Linux distribution...
  95 FROM williamyeh/ansible:ubuntu14.04
  96 #FROM williamyeh/ansible:ubuntu12.04
  97 #FROM williamyeh/ansible:debian8
  98 #FROM williamyeh/ansible:debian7
  99 #FROM williamyeh/ansible:centos7
 100 #FROM williamyeh/ansible:centos6
 101
 102
 103 # ==> Copying Ansible playbook...
 104 WORKDIR /tmp
 105 COPY  .  /tmp
 106
 107 # ==> Creating inventory file...
 108 RUN echo localhost > inventory
 109
 110 # ==> Executing Ansible...
 111 RUN ansible-playbook -i inventory playbook.yml \
 112       --connection=local --sudo
 113 ```
 114
 115 Or, more simple with `onbuild` series:
 116
 117 ```dockerfile
 118 # Dockerfile
 119
 120 # ==> Choose a base image to emulate Linux distribution...
 121 FROM williamyeh/ansible:ubuntu14.04-onbuild
 122 #FROM williamyeh/ansible:ubuntu12.04-onbuild
 123 #FROM williamyeh/ansible:debian8-onbuild
 124 #FROM williamyeh/ansible:debian7-onbuild
 125 #FROM williamyeh/ansible:centos7-onbuild
 126 #FROM williamyeh/ansible:centos6-onbuild
 127
 128
 129 # ==> Specify playbook filename;   default = "playbook.yml"
 130 #ENV PLAYBOOK   playbook.yml
 131
 132 # ==> Specify inventory filename;  default = "/etc/ansible/hosts"
 133 #ENV INVENTORY  inventory.ini
 134
 135 # ==> Executing Ansible...
 136 RUN ansible-playbook-wrapper
 137 ```
 138
 139
 140
 141 With Docker, we can test any Ansible playbook against any version of any Linux distribution without the help of Vagrant. More lightweight, and more portable across IaaS, PaaS, and even CaaS (Container as a Service) providers!
 142
 143 If better OS emulation (virtualization) isn't required, the Docker approach (containerization) should give you a more efficient Ansible experience.
 144
 145
 146
 147 ## License
 148
 149 Author: William Yeh <william.pjyeh@gmail.com>
 150
 151 Licensed under the Apache License V2.0. See the [LICENSE file](LICENSE) for details.