Ansible Cheatsheet

ansible-playbook-example.yml

---
- hosts: all
  become: true
  vars:
    package: vim # Deifines a global variables that can be used across the playbook
    packages: [ 'vim', 'git', 'curl' ] # Stor array in a variable
    doc_root: /var/www/example
  tasks:
    # Installing a single package
    - name: Install a single Package
      apt: name={{ package }} state=latest # apt is Ansible's builtin module. 
       
    # Installing multiple packages using a loop
    - name: Install Packages
      apt: name={{ item }} state=latest
      with_items: # Loop with multiple items. Reference each with {{ item }}
        - vim
        - git
        - curl
           
    # Conditionally execute a task using when
    - name: Shutdown Debian Based Systems
      command: /sbin/shutdown -t now
      when: ansible_os_family == "Debian"

    # Conditionally use result of one task in other task using register
    - name: Check if PHP is installed
      register: php_installed # Store resutlt of task in a variable
      command: php -v
      ignore_errors: true # Continue executing other tasks even if this task fails

    - name: This task is only executed if PHP is installed
      debug: var=php_install # debug: var is used to print content of variable
      when: php_installed|success # Use variable from previous task to conditionally execute this task

    - name: This task is only executed if PHP is NOT installed
      debug: msg='PHP is NOT installed' # debug: msg us used to print a string
      when: php_installed|failed
      
    # Example task showing how to use templates
    - name: Change default Apache virtual host
      template: # Template module is used to create a file using a template
        src: ansible-template-example.tpl # doc_root variable is available in this file
        
    # Triggering handler via notify
    - name: Change default Apache virtual host
      template:
        src: vhost.tpl
        dest: /etc/apache2/sites-available/000-default.conf
      notify: restart apache
        dest: /etc/apache2/sites-available/000-default.conf

    # Handlers can only to be triggered via notify in tasks. Handlers can also be placed in separate files
    # Handlers trigger state change in services (restart or a stop)
    handlers:
      - name: restart apache
        service: name=apache2 state=restarted

      - name: other handler
        service: name=other state=restarted

ansible-template-example.tpl

<!-- doc_root is a replacable variable -->
<VirtualHost *:80>
    ServerAdmin webmaster@localhost
    DocumentRoot {{ doc_root }}

    <Directory {{ doc_root }}>
        AllowOverride All
        Require all granted
    </Directory>
</VirtualHost>