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Collections

Collections are a distribution format for Ansible content. They can be used to package and distribute playbooks, roles, modules, and plugins. You can publish and use collections through Ansible Galaxy.

Important

This feature is available in Ansible 2.8 as a Technology Preview and therefore is not fully supported. It should only be used for testing and should not be deployed in a production environment. Future Galaxy or Ansible releases may introduce breaking changes.

Collection structure

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

Note

  • Ansible only accepts .yml extensions for galaxy.yml.
  • See the draft collection for an example of a full 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 :ref:`collections_galaxy_meta` for details.

docs directory

Keep general documentation for the collection here. Plugins and modules still keep their specific documentation embedded as Python docstrings. Use the docs folder to describe how to use the roles and plugins the collection provides, role requirements, and so on. Currently we are looking at Markdown as the standard format for documentation files, but this is subject to change.

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 namespace and my_collection is the collection name within that namespace.

Note

The Ansible collection namespace is defined in the galaxy.yml file and is not equivalent to the GitHub repository name.

plugins directory

Add a 'per plugin type' specific subdirectory here, including module_utils which is usable not only by modules, but by any other plugin 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.

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 ansible_example, the collection is community. In the Python example the module_util in question is called qradar such that the FQCN is ansible_example.community.plugins.module_utils.qradar:

from ansible.module_utils.basic import AnsibleModule
from ansible.module_utils._text 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.ansible_example.community.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']
)

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

#!powershell
#AnsibleRequires -CSharpUtil Ansible.Basic
#AnsibleRequires -PowerShell ansible_collections.ansible_example.community.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 man 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.

playbooks directory

TBD.

tests directory

TBD. Expect tests for the collection itself to reside here.

Creating collections

To create a collection:

  1. Initialize a collection with :ref:`ansible-galaxy collection init<creating_collections_skeleton>` to create the skeleton directory structure.
  2. Add your content to the collection.
  3. Build the collection into a collection artifact with :ref:`ansible-galaxy collection build<building_collections>`.
  4. Publish the collection artifact to Galaxy with :ref:`ansible-galaxy collection publish<publishing_collections>`.

A user can then install your collection on their systems.

Note

Any references to ansible-galaxy below will be of a 'working version' that is in development for the 2.9 release. As such, the command and this documentation section is subject to frequent changes.

Currently the ansible-galaxy collection command implements the following sub commands:

  • init: Create a basic collection skeleton based on the default template included with Ansible or your own template.
  • build: Create a collection artifact that can be uploaded to Galaxy or your own repository.
  • publish: Publish a built collection artifact to Galaxy.
  • install: Install one or more collections.

To learn more about the ansible-galaxy cli tool, see the :ref:`ansible-galaxy` man page.

Creating a collection skeleton

To start a new collection:

collection_dir#> ansible-galaxy collection init my_namespace.my_collection

Then you can populate the directories with the content you want inside the collection. See https://github.com/bcoca/collection to get a better idea of what you can place inside a collection.

Building collections

To build a collection, run ansible-galaxy collection build from inside the root directory of the collection:

collection_dir#> ansible-galaxy collection build

This creates a tarball of the built collection in the current directory which can be uploaded to Galaxy.:

my_collection/
├── galaxy.yml
├── ...
├── my_namespace-my_collection-1.0.0.tar.gz
└── ...

Note

Certain files and folders are excluded when building the collection artifact. This is not currently configurable and is a work in progress so the collection artifact may contain files you would not wish to distribute.

This tarball is mainly intended to upload to Galaxy as a distribution method, but you can use it directly to install the collection on target systems.

Publishing collections

You can publish collections to Galaxy using the ansible-galaxy collection publish command or the Galaxy UI itself.

Note

Once you upload a version of a collection, you cannot delete or modify that version. Ensure that everything looks okay before you upload it.

Upload using ansible-galaxy

To upload the collection artifact with the ansible-galaxy command:

ansible-galaxy collection publish path/to/my_namespace-my_collection-1.0.0.tar.gz --api-key=SECRET

The above command triggers an import process, just as if you uploaded the collection through the Galaxy website. The command waits until the import process completes before reporting the status back. If you wish to continue without waiting for the import result, use the --no-wait argument and manually look at the import progress in your My Imports page.

The API key is a secret token used by Ansible Galaxy to protect your content. You can find your API key at your Galaxy profile preferences page.

Upload from the Galaxy website

To upload your collection artifact directly on Galaxy:

  1. Go to the My Content page, and click the Add Content button on one of your namespaces.
  2. From the Add Content dialogue, click Upload New Collection, and select the collection archive file from your local filesystem.

When uploading collections it doesn't matter which namespace you select. The collection will be uploaded to the namespace specified in the collection metadata in the galaxy.yml file. If you're not an owner of the namespace, the upload request will fail.

Once Galaxy uploads and accepts a collection, you will be redirected to the My Imports page, which displays output from the import process, including any errors or warnings about the metadata and content contained in the collection.

Collection versions

Once you upload a version of a collection, you cannot delete or modify that version. Ensure that everything looks okay before uploading. The only way to change a collection is to release a new version. The latest version of a collection (by highest version number) will be the version displayed everywhere in Galaxy; however, users will still be able to download older versions.

Collection versions use Sematic Versioning <https://semver.org/> for version numbers. Please read the official documentation for details and examples. In summary:

  • Increment major (for example: x in x.y.z) version number for an incompatible API change.
  • Increment minor (for example: y in x.y.z) version number for new functionality in a backwards compatible manner.
  • Increment patch (for example: z in x.y.z) version number for backwards compatible bug fixes.

Migrating Ansible content to a collection

You can experiment with migrating existing modules into a collection using the content_collector tool. The content_collector is a playbook that helps you migrate content from an Ansible distribution into a collection.

Warning

This tool is in active development and is provided only for experimentation and feedback at this point.

See the content_collector README for full details and usage guidelines.

Installing collections

You can use the ansible-galaxy collection install command to install a collection on your system. The collection by default is installed at /path/ansible_collections/my_namespace/my_collection. You can optionally add the -p option to specify an alternate location.

To install a collection hosted in Galaxy:

ansible-galaxy collection install my_namespace.my_collection -p /path

You can also directly use the tarball from your build:

ansible-galaxy collection install my_namespace-my_collection-1.0.0.tar.gz -p ./collections/ansible_collections

Note

The install command automatically appends the path ansible_collections to the one specified with the -p option unless the parent directory is already in a folder called ansible_collections.

You should use one of the values configured in :ref:`COLLECTIONS_PATHS` for your path. This is also where Ansible itself will expect to find collections when attempting to use them.

You can also keep a collection adjacent to the current playbook, under a collections/ansible_collections/ directory structure.

play.yml
├── collections/
│   └── ansible_collections/
│               └── my_namespace/
│                   └── my_collection/<collection structure lives here>

Installing an older version of a collection

By default ansible-galaxy installs the latest collection that is available but you can add a version range identifier to install a specific version.

To install the 1.0.0 version of the collection:

ansible-galaxy collection install my_namespace.my_collection:1.0.0

To install the 1.0.0-beta.1 version of the collection:

ansible-galaxy collection install my_namespace.my_collection:==1.0.0-beta.1

To install the collections that are greater than or equal to 1.0.0 or less than 2.0.0:

ansible-galaxy collection install my_namespace.my_collection:>=1.0.0,<2.0.0

You can specify multiple range identifiers which are split by ,. You can use the following range identifiers:

  • *: Any version, this is the default used when no range specified is set.
  • !=: Version is not equal to the one specified.
  • ==: Version must be the one specified.
  • >=: Version is greater than or equal to the one specified.
  • >: Version is greater than the one specified.
  • <=: Version is less than or equal to the one specified.
  • <: Version is less than the one specified.

Note

The ansible-galaxy command ignores any pre-release versions unless the == range identifier is used to explicitly set to that pre-release version.

Install multiple collections with a requirements file

You can also setup a requirements.yml file to install multiple collections in one command. This file is a YAML file in the format:

---
collections:
# With just the collection name
- my_namespace.my_collection

# With the collection name, version, and source options
- name: my_namespace.my_other_collection
  version: 'version range identifiers (default: ``*``)'
  source: 'The Galaxy URL to pull the collection from (default: ``--api-server`` from cmdline)'

The version key can take in the same range identifier format documented above.

Roles can also be specified and placed under the roles key. The values follow the same format as a requirements file used in older Ansible releases.

Note

While both roles and collections can be specified in one requirements file, they need to be installed separately. The ansible-galaxy role install -r requirements.yml will only install roles and ansible-galaxy collection install -r requirements.yml -p ./ will only install collections.

Galaxy server configuration list

By default running ansible-galaxy will use the :ref:`galaxy_server` config value or the --server command line argument when it performs an action against a Galaxy server. The ansible-galaxy collection install supports installing collections from multiple servers as defined in the :ref:`ansible_configuration_settings_locations` file using the :ref:`galaxy_server_list` configuration option. To define multiple Galaxy servers you have to create the following entries like so:

[galaxy]
server_list = my_org_hub, release_galaxy, test_galaxy

[galaxy_server.my_org_hub]
url=https://automation.my_org/
username=my_user
password=my_pass

[galaxy_server.release_galaxy]
url=https://galaxy.ansible.com/
token=my_token

[galaxy_server.test_galaxy]
url=https://galaxy-dev.ansible.com/
token=my_token

Note

You can use the --server command line argument to select an explicit Galaxy server in the server_list and the value of this arg should match the name of the server. If the value of --server is not a pre-defined server in ansible.cfg then the value specified will be the URL used to access that server and all pre-defined servers are ignored. Also the --api-key argument is not applied to any of the pre-defined servers, it is only applied if no server list is defined or a URL was specified by --server.

The :ref:`galaxy_server_list` option is a list of server identifiers in a prioritized order. When searching for a collection, the install process will search in that order, e.g. my_org_hub first, then release_galaxy, and finally test_galaxy until the collection is found. The actual Galaxy instance is then defined under the section [galaxy_server.{{ id }}] where {{ id }} is the server identifier defined in the list. This section can then define the following keys:

  • url: The URL of the galaxy instance to connect to, this is required.
  • token: A token key to use for authentication against the Galaxy instance, this is mutually exclusive with username
  • username: The username to use for basic authentication against the Galaxy instance, this is mutually exclusive with token
  • password: The password to use for basic authentication

As well as being defined in the ansible.cfg file, these server options can be defined as an environment variable. The environment variable is in the form ANSIBLE_GALAXY_SERVER_{{ id }}_{{ key }} where {{ id }} is the upper case form of the server identifier and {{ key }} is the key to define. For example I can define token for release_galaxy by setting ANSIBLE_GALAXY_SERVER_RELEASE_GALAXY_TOKEN=secret_token.

For operations where only one Galaxy server is used, i.e. publish, info, login then the first entry in the server_list is used unless an explicit server was passed in as a command line argument.

Note

Once a collection is found, any of its requirements are only searched within the same Galaxy instance as the parent collection. The install process will not search for a collection requirement in a different Galaxy instance.

Using collections

Once installed, you can reference a collection content by its FQCN:

- hosts: all
  tasks:
    - my_namespace.my_collection.mymodule:
        option1: value

This works for roles or any type of plugin distributed within the collection:

- hosts: all
  tasks:
    - import_role:
        name: my_namespace.my_collection.role1

    - my_namespace.mycollection.mymodule:
        option1: value

    - debug:
        msg: '{{ lookup("my_namespace.my_collection.lookup1", 'param1')| my_namespace.my_collection.filter1 }}'

To avoid a lot of typing, you can use the collections keyword added in Ansible 2.8:

- hosts: all
  collections:
   - my_namespace.my_collection
  tasks:
    - import_role:
        name: role1

    - mymodule:
        option1: value

    - debug:
        msg: '{{ lookup("my_namespace.my_collection.lookup1", 'param1')| my_namespace.my_collection.filter1 }}'

This keyword creates a 'search path' for non namespaced plugin references. It does not import roles or anything else. Notice that you still need the FQCN for non-action or module plugins.