Install and configure docker

handlers/main.yml

+---
+# file: roles/docker/handlers/main.yml
+
+- name: "Add Docker to Boot-List"
+  command: update-rc.d docker defaults
+
+- name: "Start Docker"
+  service:
+    name='docker'
+    state='started'

tasks/install.yml

+---
+# file: roles/docker/tasks/install.yml
+
+- name: "Apt Key"
+  apt_key:
+    keyserver='p80.pool.sks-keyservers.net'
+    id='58118E89F3A912897C070ADBF76221572C52609D'
+    state=present
+
+- name: "Apt Repository"
+  apt_repository:
+    repo='deb https://apt.dockerproject.org/repo ubuntu-{{ ansible_distribution_release }} main'
+    state='present'
+    mode=644
+
+- name: "Install Docker Engine"
+  apt:
+    pkg='docker-engine'
+    state='installed'
+    update_cache=yes
+  notify:
+    - "Add Docker to Boot-List"
+    - "Start Docker"
+
+- name: "Install Python Dependencies"
+  pip:
+    name='docker-py'

tasks/main.yml

+---
+# file: roles/docker/tasks/main.yml
+
+- name: "Docker Role"
+  set_fact: role_docker_started=true
+  tags: always
+
+- block:
+
+  - include: install.yml
+
+  when: '"docker" not in excluded_roles'