L5 Managing complex playbooks with roles and ansible galaxy

(Create group:user on linux machine)

1、Simple way to create `group:user`

.
├── 3-1create_play.yml
├── tasks
│   └── create_user.yml
└── templates
    └── bashrc.j2

1-1 `3-1create_play.yml`

---
- hosts: all
  vars:
    user_name: jacob
    user_state: present
    # user_state: absent
    ssh_key: ~/.ssh/id_rsa.pub
  tasks:
     - include_tasks: tasks/create_user.yml

Defining variables in a playbook

hosts: all
  vars:
    user_name: jacob
    user_state: present
    # user_state: absent
    ssh_key: ~/.ssh/id_rsa.pub

Defining tasks
include_tasks – Dynamically include a task list: - include_tasks: tasks/create_user.yml

1-2 `tasks/create_user.yml`

---
# tasks file for user_create
- name: Create user on remote host
  user:
    name: '{{user_name}}'
    state: '{{user_state}}'
    remove: yes
    shell: /bin/bash
    groups: vagrant
    append: yes
  become: yes
  become_method: "sudo"

- name: Publish local ssh public key for remote login
  authorized_key:
    user: '{{user_name}}'
    state: '{{user_state}}'
    key: "{{ lookup('file', '{{ssh_key}}') }}"
  become: yes
  become_method: "sudo"

- name: Add bashrc to include host and user
  template:
    dest: '~{{user_name}}/.bashrc'
    src: templates/bashrc.j2
  become: yes
  become_method: "sudo"

1-3 user – Manage user accounts

Manage user accounts and user attributes.

name: Name of the user to create, remove or modify.
state: [absent / present] Whether the account should exist or not, taking action if the state is different from what is stated.
remove: When state is 'absent' and user exists Whether or not to remove the user account
shell: When state is 'absent' and user existsWhether or not to remove the user account
groups: Optionally sets the user's primary group (takes a group name).
append: When state is 'present' and the user exists Whether or not to append the user to groups

Check Linux existing user and group

$ groups
vagrant

$ awk -F: '{ print $1}' /etc/passwd
users...

Errors:

fatal: [githost]: FAILED! => {"changed": false, "cmd": "/sbin/useradd -G vagrant -s /bin/bash -m jacob", "msg": "[Errno 13] Permission denied", "rc": 13}

become: yes
become_method: "sudo"

1-4 `authorized_key` – Adds or removes an SSH authorized key

authorized_key:
    user: '{{user_name}}'
    state: '{{user_state}}'
    key: "{{ lookup('file', '{{ssh_key}}') }}"

key: The SSH public key(s), as a string or (since Ansible 1.9) url
lookup: {{ lookup('file', '{{ssh_key}}') }}

1-5 Jinja template

template:
    dest: '~{{user_name}}/.bashrc'
    src: templates/bashrc.j2

Run the play book

ansible-playbook -i ../inventory.ini 3-1create_play.yml

2、Comprehenisve role to create `group:user` with `ansible galxy`

ansible-galaxy init create_user

galaxy is a directory of roles.

So when people find something really useful like let's deploy Apache or Engine X web servers, we can create a role for that and store it in galaxy and then share amongst not only our local peers but potentially the internet at large.

cp tasks/create_user.yml create_user/tasks/main.yml
cp templates/bashrc.j2 create_user/templates/

$ tree create_user/
create_user/
├── README.md
├── defaults
│   └── main.yml
├── files
├── handlers
│   └── main.yml
├── meta
│   └── main.yml
├── tasks
│   └── main.yml
├── templates
│   └── bashrc.j2
├── tests
│   ├── inventory
│   └── test.yml
└── vars
    └── main.yml

8 directories, 9 files

2-1 `3-1create_role.yml`

---
- hosts: all
  tasks:
    - include_role:
          name: create_user
      vars:
        user_name: jacob
        # user_state: present
        user_state: absent
        ssh_key: ~/.ssh/id_rsa.pub

2-2 `tasks/main.yml`

---
# tasks file for user_create
- name: Create user on remote host
  user:
    name: '{{user_name}}'
    state: '{{user_state}}'
    remove: yes
    shell: /bin/bash
    groups: vagrant
    append: yes
  become: yes
  become_method: "sudo"

- name: Publish local ssh public key for remote login
  authorized_key:
    user: '{{user_name}}'
    state: '{{user_state}}'
    key: "{{ lookup('file', '{{ssh_key}}') }}"
  become: yes
  become_method: "sudo"

- name: Add bashrc to include host and user
  template:
    dest: '~{{user_name}}/.bashrc'
    src: templates/bashrc.j2
  become: yes
  become_method: "sudo"

2-3 `templates/bashrc.j2`

export PS1='{{inventory_hoastname}}:{{user_name}} $'

ansible-playbook -i ../inventory.ini 3-2create_role.yml

3、Variables in roles and variable precedence

3-1 `3-1create_role.yml` Delete `user_state` from tasks

---
- hosts: all
  tasks:
    - include_role:
          name: create_user
      vars:
        user_name: jacob
        # user_state: present
        # user_state: absent
        ssh_key: ~/.ssh/id_rsa.pub

3-2 Add this is variable in `default/main.yml`

---
# defaults file for create_user
 user_state: present

ansible-playbook -i ../inventory.ini 3-2create_role.yml

3-3 Add this is variable can be also passed in `default/main.yml`

ansible-playbook -i ../inventory.ini 3-2create_role.yml -e user_state= absent

-e user_state= absent

4、Role-based templates

Add more variables default/main.yml

---
# defaults file for create_user
user_state: present
user_name: default

4-1 Dont forget document newly added variables： `READEME.md`

Role Variables
--------------

# Define the user you would like to create
user_name: default

# Define the user state present or absent
user_state: present

5、Documenting your role for reuse

5-1 `READEME.md`

Role Variables
--------------

# Define the user you would like to create
user_name: default

# Define the user state present or absent
user_state: present

# Define the path to the ssh public key
ssh_key: ~/.ssh/id_rsa.pub


Dependencies
------------

None

Example Playbook
----------------

---
- hosts: all
  tasks:
    - include_role:
          name: create_user
      vars:
        user_name: jacob
        ssh_key: ~/.ssh/id_rsa.pub

License
-------

MIT

Author Information
------------------

...

5-2 `meta/main.yml`

galaxy_info:
  author: jaocb
  description: Create user with ssh authentication
  company: your company (optional)

 license: MIT 

 min_ansible_version: 2.4

 galaxy_tags: [user,admin]

6、Pushing a role to Galaxy

Step one push projects into github
ansible-galaxy login with github token(username and password)
ansible-galaxy import chao-xi(repo_owner) create_user(project_name)

7、Finding roles via Ansible Galaxy

7-1 Search

ansible-galaxy search create_user

Found 1816 roles matching your search. Showing first 1000.

 Name                                                      Description
 ----                                                      -----------
 0utsider.ansible_zabbix_agent                             Installing and maintaining zabbix-agent for RedHat/Debian/Ub
 0x5a17ed.ansible_role_netbox                              Installs and configures NetBox, a DCIM suite, in a productio
 1davidmichael.ansible-role-nginx                          Nginx installation for Linux, FreeBSD and OpenBSD.
 1it.users                                                 Ansible role 
 ...

7-2 download

$ ansible-galaxy search create_user | grep docker
 alexinthesky.docker                                       Install Docker and Docker Compose.


$ ansible-galaxy install alexinthesky.docker -p ./
- downloading role 'docker', owned by alexinthesky
- downloading role from https://github.com/alexinthesky/ansible-docker/archive/v0.1.6.tar.gz
- extracting alexinthesky.docker to /Users/i515190/Devops_sap/ansible/code/task3/alexinthesky.docker
- alexinthesky.docker (v0.1.6) was installed successfully

$  tree alexinthesky.docker
alexinthesky.docker
├── CHANGES.md
├── LICENSE
├── README.md
├── defaults
│   └── main.yml
├── handlers
│   └── main.yml
├── meta
│   └── main.yml
├── tasks
│   └── main.yml
├── templates
│   └── etc
│       └── systemd
│           └── system
│               └── docker.service.j2
└── tests
    ├── inventory
    └── main.yml

9 directories, 10 files

Centralizing roles with roles_path

$ vi /etc/ansible/ansible.cfg

[defaults]
role_path=/etc/ansible/roles

L5 Managing complex playbooks with roles and ansible galaxy

1、Simple way to create group:user

1-1 3-1create_play.yml

1-2 tasks/create_user.yml

1-3 user – Manage user accounts

1-4 authorized_key – Adds or removes an SSH authorized key

1-5 Jinja template

2、Comprehenisve role to create group:user with ansible galxy

2-1 3-1create_role.yml

2-2 tasks/main.yml

2-3 templates/bashrc.j2