1ansible -i <invetory_file> <group> -m command -a <command> == ansible -i <invetory_file> <group> -a <command>

1- name: Create users
2  user:
3    name: "{{ item }}"
4    state: present
5  with_items:
6    - user1
7    - user2
8    - user3

1vars:
2  users:
3    - user1
4    - user2
5    - user3
6 
7tasks:
8- name: Create users
9  user:
10    name: "{{ item }}"
11    state: present
12  with_items: "{{ users }}"

1- hosts: <group>
2  become: yes
3 
4  vars:
5    - vars.yml
6    - another_vars.yml

1---
2...ansible
3 
4	handlers:
5		- name: <handler-task-name>
6		  <module>: <do-something>
7	tasks:
8		- name: <task-name>
9		  <module>: <do-something>
10		  notify: |
11		    <handler-task-name> # Will trigger the handler with `handler-task-name`
12		- name: Make sure handler is flushed immediately.
13		  meta: flush_handlers

1handlers:
2  - name: restart apache
3    service:
4      name: httpd
5      state: restarted
6    notify: restart memcached
7 
8  - name: restart memcached
9    service:
10      name: memcached
11      state: restarted

1- name: Start NodeJS app
2  command: ...
3  when: <registered_var>.stdout.find(<string>) == -1

1- name: restart memcached
2  service:
3    name: memcached
4    state: restarted
5  tags: [restartable, services]

1tasks:
2  - name: Handle the error
3    block:
4      - name: Print a message
5        ansible.builtin.debug:
6          msg: 'I execute normally'
7 
8      - name: Force a failure
9        ansible.builtin.command: /bin/false
10 
11      - name: Never print this
12        ansible.builtin.debug:
13          msg: 'I never execute, due to the above task failing, :-('
14    rescue:
15      - name: Print when errors
16        ansible.builtin.debug:
17          msg: 'I caught an error, can do stuff here to fix it, :-)'
18    always:
19      - name: Always do this
20        ansible.builtin.debug:
21          msg: "This always executes, :-)"

1handlers:
2  - import_tasks: handlers/apache.yml

1- import_playbook: <playbook-name>.yml

1vars:
2  proxy_vars:
3    http_proxy: ...
4    https_proxy: ...

1proxy_vars:
2  http_proxy: ...
3  https_proxy: ...

1vars_files:
2  - file_path_one/file.yml
3  - file_path_two/file.yml

1pre_tasks:
2  - debug: var=ansible_os_family
3  - name: Load the first vars file found
4    include_vars:
5      - "vars/apache_{{ ansible_os_family }}.yml"
6      - "vars/apache_default.yml"

1[<group>]
2x.x.x.x
3 
4[<group>:vars]
5ansible_user=root
6ansible_ssh_private_key_file=<path>

1# tasks
2- name: Capture env variable value for $HOME
3  shell: 'source ~/.bash_profile/ && echo "${HOME}"'
4  register: home_env_var
5 
6- debug: msg="Users home is {{ home_env_var.stdout }}"

1roles/
2  <role-name>
3    meta/
4      main.yml # <-- `dependencies: []`
5    tasks/
6      main.yml # <-- `task list`

1---
2- hosts: 127.0.0.1
3  gather_facts: no
4  connection: local
5 
6  vars:
7    should_fail_via_fail: true
8    should_fail_via_assert: true
9    should_fail_via_complex_assert: true
10 
11  tasks:
12    - name: Fail if conditions warrant a failure.
13      fail:
14        msg: "There was an epic failure"
15      when: should_fail_via_fail
16 
17    - name: Stop playbook if an assertion isn't validated.
18      assert:
19        that: "should_fail_via_assert != true"
20 
21    - name: Assertions can have contains conditions.
22      assert:
23        that:
24          - should_fail_via_fail != true
25          - should_fail_via_assert != true
26          - should_fail_via_complex_assert != true

1# Install a role globally
2ansible-galaxy role install <role> # <gerlingguy.homebrev>

1---
2roles:
3  - name: elliotweiser.osx-command-line-tools
4    version: 2.3.0
5  - name: gerlingguy.homebrev
6    version: 3.1.0

1- name: another task
2  <command>: ...
3- debug: msg="A task without a name"
4- name: another task
5  <command>: ...