Collection structure

A collection is a simple data structure. None of the directories are required unless you have specific content that belongs in one of them. A collection does require a galaxy.yml file at the root level of the collection. This file contains all of the metadata that Galaxy and other tools need in order to package, build and publish the collection.

Collection directories and files

A collection can contain these directories and files:

collection/
├── docs/
├── galaxy.yml
├── meta/
│   └── runtime.yml
├── plugins/
│   ├── modules/
│   │   └── module1.py
│   ├── inventory/
│   └── .../
├── README.md
├── roles/
│   ├── role1/
│   ├── role2/
│   └── .../
├── playbooks/
│   ├── files/
│   ├── vars/
│   ├── templates/
│   └── tasks/
└── tests/

Note

  • Ansible only accepts .md extensions for the README file and any files in the /docs folder.

  • See the ansible-collections GitHub Org for examples of collection structure.

  • Not all directories are currently in use. Those are placeholders for future features.

galaxy.yml

A collection must have a galaxy.yml file that contains the necessary information to build a collection artifact. See Collection Galaxy metadata structure for details.

docs directory

Use the docs folder to describe how to use the roles and plugins the collection provides, role requirements, and so on.

For certified collections, Automation Hub displays documents written in markdown in the main docs directory with no subdirectories. This will not display on https://docs.ansible.com.

For community collections included in the Ansible PyPI package, docs.ansible.com displays documents written in reStructuredText (.rst) in a docsite/rst/ subdirectory. Define the structure of your extra documentation in docs/docsite/extra-docs.yml:

---
sections:
- title: Scenario Guide
  toctree:
    - scenario_guide

The index page of the documentation for your collection displays the title you define in docs/docsite/extra-docs.yml with a link to your extra documentation. For an example, see the community.docker collection repo and the community.docker collection documentation.

Plugin and module documentation

Keep the specific documentation for plugins and modules embedded as Python docstrings. Use ansible-doc to view documentation for plugins inside a collection:

ansible-doc -t lookup my_namespace.my_collection.lookup1

The ansible-doc command requires the fully qualified collection name (FQCN) to display specific plugin documentation. In this example, my_namespace is the Galaxy namespace and my_collection is the collection name within that namespace.

Note

The Galaxy namespace of an Ansible collection is defined in the galaxy.yml file. It can be different from the GitHub organization or repository name.

plugins directory

Add a ‘per plugin type’ specific subdirectory here, including module_utils which is usable not only by modules, but by most plugins by using their FQCN. This is a way to distribute modules, lookups, filters, and so on without having to import a role in every play.

Vars plugins are unsupported in collections. Cache plugins may be used in collections for fact caching, but are not supported for inventory plugins.

module_utils

When coding with module_utils in a collection, the Python import statement needs to take into account the FQCN along with the ansible_collections convention. The resulting Python import will look like from ansible_collections.{namespace}.{collection}.plugins.module_utils.{util} import {something}

The following example snippets show a Python and PowerShell module using both default Ansible module_utils and those provided by a collection. In this example the namespace is community, the collection is test_collection. In the Python example the module_util in question is called qradar such that the FQCN is community.test_collection.plugins.module_utils.qradar:

from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils.common.text.converters import to_text

from ansible.module_utils.six.moves.urllib.parse import urlencode, quote_plus
from ansible.module_utils.six.moves.urllib.error import HTTPError
from ansible_collections.community.test_collection.plugins.module_utils.qradar import QRadarRequest

argspec = dict(
    name=dict(required=True, type='str'),
    state=dict(choices=['present', 'absent'], required=True),
)

module = AnsibleModule(
    argument_spec=argspec,
    supports_check_mode=True
)

qradar_request = QRadarRequest(
    module,
    headers={"Content-Type": "application/json"},
    not_rest_data_keys=['state']
)

Note that importing something from an __init__.py file requires using the file name:

from ansible_collections.namespace.collection_name.plugins.callback.__init__ import CustomBaseClass

In the PowerShell example the module_util in question is called hyperv such that the FQCN is community.test_collection.plugins.module_utils.hyperv:

#!powershell
#AnsibleRequires -CSharpUtil Ansible.Basic
#AnsibleRequires -PowerShell ansible_collections.community.test_collection.plugins.module_utils.hyperv

$spec = @{
    name = @{ required = $true; type = "str" }
    state = @{ required = $true; choices = @("present", "absent") }
}
$module = [Ansible.Basic.AnsibleModule]::Create($args, $spec)

Invoke-HyperVFunction -Name $module.Params.name

$module.ExitJson()

roles directory

Collection roles are mostly the same as existing roles, but with a couple of limitations:

  • Role names are now limited to contain only lowercase alphanumeric characters, plus _ and start with an alpha character.

  • Roles in a collection cannot contain plugins any more. Plugins must live in the collection plugins directory tree. Each plugin is accessible to all roles in the collection.

The directory name of the role is used as the role name. Therefore, the directory name must comply with the above role name rules. The collection import into Galaxy will fail if a role name does not comply with these rules.

You can migrate ‘traditional roles’ into a collection but they must follow the rules above. You may need to rename roles if they don’t conform. You will have to move or link any role-based plugins to the collection specific directories.

Note

For roles imported into Galaxy directly from a GitHub repository, setting the role_name value in the role’s metadata overrides the role name used by Galaxy. For collections, that value is ignored. When importing a collection, Galaxy uses the role directory as the name of the role and ignores the role_name metadata value.

tests directory

Ansible Collections are tested much like Ansible itself, by using the ansible-test utility which is released as part of Ansible, version 2.9.0 and newer. Because Ansible Collections are tested using the same tooling as Ansible itself, via ansible-test, all Ansible developer documentation for testing is applicable for authoring Collections Tests with one key concept to keep in mind.

See Testing collections for specific information on how to test collections with ansible-test.

When reading the Testing Ansible documentation, there will be content that applies to running Ansible from source code via a git clone, which is typical of an Ansible developer. However, it’s not always typical for an Ansible Collection author to be running Ansible from source but instead from a stable release, and to create Collections it is not necessary to run Ansible from source. Therefore, when references of dealing with ansible-test binary paths, command completion, or environment variables are presented throughout the Testing Ansible documentation; keep in mind that it is not needed for Ansible Collection Testing because the act of installing the stable release of Ansible containing ansible-test is expected to setup those things for you.

meta directory

A collection can store some additional metadata in a runtime.yml file in the collection’s meta directory. The runtime.yml file supports the top level keys:

  • requires_ansible:

    The version of Ansible required to use the collection. Multiple versions can be separated with a comma.

    requires_ansible: ">=2.10,<2.11"
    

    Note

    although the version is a PEP440 Version Specifier under the hood, Ansible deviates from PEP440 behavior by truncating prerelease segments from the Ansible version. This means that Ansible 2.11.0b1 is compatible with something that requires_ansible: ">=2.11".

  • plugin_routing:

    Content in a collection that Ansible needs to load from another location or that has been deprecated/removed. The top level keys of plugin_routing are types of plugins, with individual plugin names as subkeys. To define a new location for a plugin, set the redirect field to another name. To deprecate a plugin, use the deprecation field to provide a custom warning message and the removal version or date. If the plugin has been renamed or moved to a new location, the redirect field should also be provided. If a plugin is being removed entirely, tombstone can be used for the fatal error message and removal version or date.

    plugin_routing:
      inventory:
        kubevirt:
          redirect: community.general.kubevirt
        my_inventory:
          tombstone:
            removal_version: "2.0.0"
            warning_text: my_inventory has been removed. Please use other_inventory instead.
      modules:
        my_module:
          deprecation:
            removal_date: "2021-11-30"
            warning_text: my_module will be removed in a future release of this collection. Use another.collection.new_module instead.
          redirect: another.collection.new_module
        podman_image:
          redirect: containers.podman.podman_image
      module_utils:
        ec2:
          redirect: amazon.aws.ec2
        util_dir.subdir.my_util:
          redirect: namespace.name.my_util
    
  • import_redirection

    A mapping of names for Python import statements and their redirected locations.

    import_redirection:
      ansible.module_utils.old_utility:
        redirect: ansible_collections.namespace_name.collection_name.plugins.module_utils.new_location
    

See also

Distributing collections

Learn how to package and publish your collection

Contributing to Ansible-maintained Collections

Guidelines for contributing to selected collections

Mailing List

The development mailing list

irc.libera.chat

#ansible IRC chat channel