freehck.var_loader

This role includes variables from specific directory.

Idea

While developing CI/CD for quite a big project, we found that it's very convenient to store environment variables in directories specific for each environment and then load them. Then we found that it's useful to split credentials and common variables into separate directories. The directories just have a structure like this:

.
├── common-vars
│   ├── project-A
│   │   └── dev
│   └── project-B
│       └── dev
├── credentials
│   ├── project-A
│   │   ├── dev
│   │   └── prod
│   └── project-B
│       ├── dev
│       └── prod
└── env-vars
    ├── project-A-env01
    ├── project-A-env02
    ├── project-A-prod
    ├── project-B-env01
    ├── project-B-env02
    └── project-B-prod

We put hosts from the same environment into one group (let's call it f.e. project-a-env01), and specify in the appropriate file under group_vars the directories to load variables from (like in example below).

The benefit of this approach is that the included variables always have the maximum priority (except of --extra-vars), so you've always got an understanding where to look for your environment paramters.

Role Variables

var_loader_root: here directories with environments are stored

var_loader_group_name: directory with environment variables, this path is relative to var_loader_root

var_loader_src: if specified, the role will load variables just from this directory

Role Defaults

var_loader_src: "{{ var_loader_root }}/{{ var_loader_group_name }}"

Example Playbook

This snippet will include all the *.yml files from playbook_dir/vars/dev:

- hosts: group-containing-all-hosts-for-dev-env
  roles:
    - role: freehck.var_loader
      var_loader_root: "{{ playbook_dir }}/vars"
      var_loader_group_name: "dev"

This snippet will include all the *.yml files from /home/user/my-env

- hosts: group-containing-all-hosts-for-dev-env
  roles:
    - role: freehck.var_loader
      var_loader_src: "/home/user/my-env"

This snippet will include all the *.yml files from: playbook_dir/creds/dev, playbook_dir/env-vars/dev, playbook_dir/common-vars/my-dev-env

--- playbook.yml ---
- hosts: group-containing-all-hosts-for-dev-env
  roles:
    # load credentials
    - role: freehck.var_loader
      var_loader_root: "{{ playbook_dir }}/creds"
      var_loader_group_name: "{{ credentials_library }}"
    # load variables specific for this environment group (group of similar environments)
    - role: freehck.var_loader
      var_loader_root: "{{ playbook_dir }}/common-vars"
      var_loader_group_name: "{{ env_group_name }}"
    # load environment specific variables
    - role: freehck.var_loader
      var_loader_root: "{{ playbook_dir }}/env-vars"
      var_loader_group_name: "{{ env_name }}"
      
--- group_vars/group-containing-all-hosts-for-dev-env.yml ---
credentials_library: "dev"
env_group_name: "dev"
env_name: "my-dev-env"

License

MIT

Author Information

Dmitrii Kashin, freehck@freehck.ru