Ansible Collections Overview

Topics

Overview
Feedback
Where we've come from, and where we are going
- Ansible 2.9 and earlier
- Ansible 2.10 and later
Terminology
Documentation
Work needed
- Timeline
FAQ

Overview

Warning: Subject to frequent updates: This is a "living document", expect it to change as we progress with the Collections work over the next few months.

As with any project it's very important that we get feedback from users, contributors and maintainers. We recognize that the move to Collections is a big change in how Ansible is developed and delivered. Therefore you should expect that the devel branch may be broken on occasion.

See the Ansible Communication channels for a list of IRC channels and email lists you can use to join the discussion. For specific issues please raise a bug report.

Where we've come from, and where we are going

To understand where we are going, it's often useful to remind ourselves of where we are today.

Ansible 2.9 and earlier

Classic Ansible

Single repository ansible/ansible.
Single package called ansible
ansible has major releases twice a year
New features go into the next major release - ie worst case you need to wait 6 months

Ansible 2.10 and later

The ansible/ansible repository will only contain:
- The core Ansible programs, ansible-{playbook,galaxy,doc,test}, etc.
- Documentation
- A tiny subset of modules and plugins to allow for a functioning controller
- Together this will be known as ansible-base
The rest of the modules and plugins will move into multiple Collections
Collections:
- Can be released independently of Ansible, at whatever release cycle/cadence the collection maintainer prefers.
- Will have their own repo (GitHub, GitLab, etc) with dedicated backlog, ie no more shared massive issue & PR backlog
- Should still have CI testing and in many cases can be tested more thoroughly
The released package of Ansible 2.10 will pull in ansible-base and the various community collections that were previously a part of ansible/ansible

Terminology

Classic Ansible (CA): What we think of as Ansible prior to 2020. The open source project and the deliverable. What you currently get (as of Ansible 2.9) when you type pip install ansible. Currently developed almost entirely within the ansible/ansible repository on GitHub.
Collection: A packaging format for bundling and distributing Ansible content: plugins, roles, modules. Can be released independent of other collections or ansible-base so features can be made available sooner to users. Installed via ansible-galaxy collection install <namespace.collection>.
Ansible Base: The codebase that will be contained in github.com/ansible/ansible for the Ansible 2.10 release. Contains a minimal amount of modules and plugins, allows other collections to be installed. Similar to Ansible 2.9 though without any content that has since moved into a collection. The devel branch of ansible/ansible is now ansible-base.

There will be an ansible-base package (ie a RPM/Python/Deb package with only the minimal set of modules and plugins).

Ansible Community Content Collections: The collections which host the modules and plugins, previously in Ansible 2.9, which are managed by the community. These collections will be combined and released when you do $package_manager install ansible. These may run at different cadences, and may now be installed individually by users via Ansible Galaxy.
Ansible Galaxy: An online hub for finding and sharing Ansible community content. Also, the command-line utility that lets users install individual Ansible Collections. galaxy.ansible.com.
Fully Qualified Collection Name (FQCN): The full definition of a module, plugin, or role hosted within a collection, in the form namespace.collection.content_name. Allows a Playbook to refer to a specific module or plugin from a specific source in an unambiguous manner, for example, community.grafana.grafana_dashboard. The FQCN is required when you want to specify the exact source of a module and multiple modules with the same name are available. Can always be identified in a playbook; ideally not necessary in most playbooks, but in cases in which users have multiple collections installed with similar content, the FQCN will always be the explicit and authoritative indicator of which collection to use for content. Example: cisco.ios.ios_config would be the FQCN, and the playbook would generally call "ios_config" when this is required.
Namespace: The first part of a Fully Qualified Collection Name, the namespace usually reflects a functional content category. Example: in cisco.ios.ios_config, “Cisco” is the Namespace. Namespaces are reserved and distributed by Red Hat at Red Hat’s discretion. Many, but not all, namespaces will correspond with vendor names.
Collection name: In the second part of a Fully Qualified Collection Name, the collection name further divides the functional characteristics of the collection content and denotes ownership. For example, the cisco namespace might contain cisco.ios, cisco.ios_community, and cisco.ios_prc, containing content for managing ios network devices maintained by Cisco.
The community.general collection: A special collection managed by the Ansible Community Team containing all the modules and plugins which shipped in Ansible 2.9 that don't have their own dedicated Collection. A work in progress can be found in community.general repository. At least initially there are no Long Term Support (LTS) plans, though we will see how the need for that grows over time.
Repository: The location of the source code included in a collection. Contributors make suggestions, fix bugs, and add features through the repository. Collection owners can host repositories on GitHub, Gerrit, or any other source code repository platform they choose.

Although this document focuses on Community (upstream) content, there will be Product (downstream) equivalents of the above. Links to the Product documentation will be added once they are available.

Documentation

Work needed

Ansible 2.9 already contains basic support for Collections.

The majority of the Ansible 2.10 release cycle is for:

Defining what the split of collections should be
Defining which modules and plugins go into these new collections
Defining ansible-base (ie which modules stay in ansible/ansible)
Updating test infrastructure
Testing the changes
Getting feedback from you

We will soon begin the migration of content out of ansible/ansible, into its new component collection repositories.

Timeline

Warning: Dates subject to change

DONE 2nd March 2020, we will freeze the devel branch using protected branches, and we will create the temp-2.10-devel branch from devel. This date marks the end of merging non-base plugin/module PRs into ansible/ansible.
DONE 9th March 2020, we will perform the initial migration against temp-2.10-devel, and we will do our initial testing of the components.
DONE 23rd March 2020, we intend to unfreeze devel and merge temp-2.10-devel back into devel. From that point on, devel for ansible/ansible will be for the ansible-base project only.
TBC, community.general accepts new Pull Requests (PRs).
TBC, the ansible package has been updated to include the Community Collections.
See ROADMAP_2.10 for dates of beta, RC, Release dates for ansible-base 2.10

FAQ

Users of Ansible

Using Ansible Collections

Q: Once the next version of Ansible is released, will my playbooks still work

For users of the community version of ansible pip/apt-get install ansible will continue to give you a working install of Ansible including the three thousand plus modules.

Q: I deploy Ansible directly from devel. Is that still advised?

We recognize that many users install Ansible directly from devel, and generally we do our best to keep the devel branch stable. These changes, however, will have a very large short-term impact, and we cannot guarantee that devel will be as stable as it has been in the past through this migration process.

These changes, however, will have both a temporary and permanent impact.

Temporarily
- These changes are large and invasive so there may be bugs which break many things.
- We cannot guarantee that devel will be as stable as it has been in the past during this transition period.
Permanent
- Users of devel will need to get both ansible (program) and the ansible collections that their playbooks rely on. The collections will reside in multiple other git repositories (or can be installed from galaxy).
- If your workflow presently updates your checkout of the ansible devel branch, you'll need to change it to also retrieve the collections you need otherwise your playbooks will fail once we migrate the contents. More information about what collections modules and plugins are migrating to to come.

Q: When will the next version of Ansible be released with these changes?

We don't have a firm date yet, but we plan to release Ansible 2.10 sometime in 2020, and we do expect to have several alpha/beta releases between now and then. Until that time, Ansible 2.9 will continue to be the supported version.

Q: I'd like to consume the development stream of Ansible during this process. How do I do that?

You can pip install ansible-base by doing:

python -m pip install --user https://github.com/ansible/ansible/archive/devel.tar.gz

Individual collections can be installed by doing:

ansible-galaxy collection install NAMESPACE.COLLECTION

Q: What exactly is ansible-base for and what does it contain

Ansible-base is the name for what github.com/ansible/ansible has become now that most of the content has been removed.

use-cases for ansible-base

ansible[|-playbook|-galaxy|-pull|-doc|-test] --help

Being able to install content from Galaxy or Automation Hub
- ansible-galaxy collection ...
- Setup Networking
- Setup Proxy
Being able to install supported content via packages
- ie RHEL users will not use ansible-galaxy collection install ..., they want RPMs
- Ability to setup and use package repos
- Ability to work online or offline
Include things that are "hardcoded" into Ansible
- eg stat is used to handle any file information internally
- include_tasks is hardcoded as the implementation is inside the engine, same with add_host, group_by, debug and others, async_wrapp, async-poll, assert/fail are 'parts of the language'
Development
- Ability to run ansible-test sanity,units,integration against the Ansible code base
Parts of the Windows codebase that can't currently be removed from ansible-base.

Bugs in ansible-base should be reported via ansible/ansible issues.

Contributors to Ansible

Developing Collections

Q: I'd like to submit a new module or plugin to Ansible. How shall I proceed?

If you're a vendor/partner and you're writing Ansible content to interact with your software, we recommend writing your own collection. This will allow you to pursue certification against the Ansible Automation Platform. For more info on certification, read here [FIXME: link].

If you want to submit your module to the community.general Collection, please wait till this repo has been created (see timeline at the top of this document).

If you want to submit your module to an existing collection, you'll want to coordinate with the maintainers of those collections and follow their guidelines. Note that not all collections will necessarily accept new modules, nor follow the guidelines that ansible/ansible previously did.

As of today ansible-base (and ansible/ansible) will no longer accept new modules.

Q: I'd like to submit a pull request to an existing Ansible module. How will I know where this module will live?

We will have a mapping of old modules to their new homes. Should you submit a PR to the wrong repository, we will close it and point you to the correct repository.

For new PRs please wait for the new Collections to be created.

Q: I have existing pull requests to existing modules that will become part of the Ansible Community Collection. What will happen to those?

Pull requests merged before ansible/ansible:devel is frozen will end up in the new collections.

Pull requests not merged before the freeze, will need to be recreated in the corresponding new Collection Repo. We will have a tool to help move PRs from one repo to another.

Source content is housed in a GitHub organization/repository of your choosing
Source content is subject to your own CI processes, decisions, and testing
Your own dedicated Issue and PR backlog
Ability to use more GitHub functionality, such as direct assignments, reviews, milestones and Project Boards

Q: What will versioning and deprecation look like for Collections

In ansible/ansible:
- There is a single version number which is over everything shipped in Ansible
- Doesn't use semver, uses X.Y (ie 2.9) as the major number
- Deprecations are done over 4 versions (~ 2 years)
In Collections
- Can be versioned and released independently to Ansible
- MUST use semver (Semantic Versioning)

Details around versioning and deprecation policy are still being worked on, we will have a proposal up shortly

Q: What should I do to move plugins across collections during migration?

PR1 Create PR against old collection repo to remove

all modules, module_utils, docs_fragments, etc
if it is an action plugin, remember to include the corresponding module with documentation.
if it is a module, check if it has a corresponding action plugin that should carry with it.
ensure meta/ has updates to action_groups.yml and routing.yml if they did in step #1.
sanity ignore lines from tests/sanity/ignore*.txt
integration tests: tests/integrations/targets/
unit tests: tests/units/plugins/
if moving from community.general remove entries from .github/BOTMETA.yml
Carefully review meta/routing.yml for any entries, in particular deprecated
Update meta/routing.yml to contain redirects for EVERY PLUGIN, pointing to the new collection name.

PR2: Create PR against new collection repo to add the files removed in step 1, as well as:

This PR MUST add all the items removed by PR1.

if it is an action plugin, remember to include the corresponding module with documentation.
if it is a module, check if it has a corresponding action plugin that should carry with it.
check meta/ for relevant updates to action_groups.yml and routing.yml if they exist.
Carefully check tests/integration, tests/units
tests/sanity/ignore-*.txt entries
meta/routing.yml

PR3: Update ansible/ansible:devel branch entries for all files moved

lib/ansible/config/routing.yml (redirect entry)
.github/BOTMETA.yml (migrated_to entry)

Q: How can I fix bugs in Ansible 2.9?

The previous policy was:

PR for bug fix including changelog/fragment file
PR gets merged into devel
Backport (git cherry-pick -x) PR against the stable-2.9 branch

Once content has been removed from the devel branch, the process will be:

PR for bug fix made against the Collection
PR gets merged into Collection
Raise PR directly against ansible/ansible:stable-2.9 (ie not a backport) including a changelog/fragment file

ericsysmin / ansible-collections-overview