path: root/README.rst

.. image:: https://img.shields.io/pypi/v/ansible-lint.svg
   :target: https://pypi.org/project/ansible-lint
   :alt: PyPI version

.. image:: https://img.shields.io/badge/Ansible--lint-rules%20table-blue.svg
   :target: https://ansible-lint.readthedocs.io/en/latest/default_rules.html
   :alt: Ansible-lint rules explanation

.. image:: https://img.shields.io/badge/Code%20of%20Conduct-black.svg
   :target: https://docs.ansible.com/ansible/latest/community/code_of_conduct.html
   :alt: Ansible Code of Conduct

.. image:: https://img.shields.io/badge/Mailing%20lists-Ansible-orange.svg
   :target: https://docs.ansible.com/ansible/latest/community/communication.html#mailing-list-information
   :alt: Ansible mailing lists

.. image:: https://github.com/ansible/ansible-lint/workflows/gh/badge.svg
   :target: https://github.com/ansible/ansible-lint/actions?query=workflow%3Agh+branch%3Amaster+event%3Apush
   :alt: GitHub Actions CI/CD

.. image:: https://img.shields.io/lgtm/grade/python/g/ansible/ansible-lint.svg?logo=lgtm&logoWidth=18
   :target: https://lgtm.com/projects/g/ansible/ansible-lint/context:python
   :alt: Language grade: Python

.. image:: https://img.shields.io/badge/pre--commit-enabled-brightgreen?logo=pre-commit&logoColor=white
   :target: https://github.com/pre-commit/pre-commit
   :alt: pre-commit


Ansible-lint
============

``ansible-lint`` checks playbooks for practices and behaviour that could
potentially be improved. As a community backed project ansible-lint supports
only the last two major versions of Ansible.

`Visit the Ansible Lint docs site <https://ansible-lint.readthedocs.io/en/latest/>`_

Installing
==========

.. installing-docs-inclusion-marker-do-not-remove

Installing on Windows is not supported because we use symlinks inside Python packages.

Using Pip
---------

.. code-block:: bash

    pip install ansible-lint

.. _installing_from_source:

From Source
-----------

**Note**: pip 19.0+ is required for installation. Please consult with the `PyPA User Guide`_
to learn more about managing Pip versions.

.. code-block:: bash

    pip install git+https://github.com/ansible/ansible-lint.git

.. _PyPA User Guide: https://packaging.python.org/tutorials/installing-packages/#ensure-pip-setuptools-and-wheel-are-up-to-date

.. installing-docs-inclusion-marker-end-do-not-remove

Usage
=====

.. usage-docs-inclusion-marker-do-not-remove

Command Line Options
--------------------

The following is the output from ``ansible-lint --help``, providing an overview of the basic command line options:

.. code-block::

    usage: ansible-lint [-h] [-L] [-f {rich,plain,rst}] [-q] [-p] [--parseable-severity] [-r RULESDIR]
                    [-R] [--show-relpath] [-t TAGS] [-T] [-v] [-x SKIP_LIST]
                    [-w WARN_LIST [WARN_LIST ...]] [--nocolor] [--force-color]
                    [--exclude EXCLUDE_PATHS] [-c CONFIG_FILE] [--version]
                    [playbook [playbook ...]]

    positional arguments:
      playbook              One or more files or paths. When missing it will enable auto-detection mode.

    optional arguments:
      -h, --help            show this help message and exit
      -L                    list all the rules
      -f {rich,plain,rst}   Format used rules output, (default: rich)
      -q                    quieter, although not silent output
      -p                    parseable output in the format of pep8
      --parseable-severity  parseable output including severity of rule
      --progressive         Return success if it detects a reduction in number of violations compared with
                            previous git commit. This feature works only on git repository clones.
      -r RULESDIR           Specify custom rule directories. Add -R to keep using embedded rules from
                            /usr/local/lib/python3.8/site-packages/ansiblelint/rules
      -R                    Keep default rules when using -r
      --show-relpath        Display path relative to CWD
      -t TAGS               only check rules whose id/tags match these values
      -T                    list all the tags
      -v                    Increase verbosity level
      -x SKIP_LIST          only check rules whose id/tags do not match these values
      -w WARN_LIST [WARN_LIST ...]
                            only warn about these rules
      --nocolor             disable colored output
      --force-color         Try force colored output (relying on ansible's code)
      --exclude EXCLUDE_PATHS
                            path to directories or files to skip. This option is repeatable.
      -c CONFIG_FILE        Specify configuration file to use. Defaults to ".ansible-lint"
      --version             show program's version number and exit

Progressive mode
----------------

In order to ease tool adoption, git users can enable the progressive mode using
``--progressive`` option. This makes the linter return a success even if
some failures are found, as long the total number of violations did not
increase since the previous commit.

As expected, this mode makes the linter run twice if it finds any violations.
The second run is performed against a temporary git working copy that contains
the previous commit. All the violations that were already present are removed
from the list and the final result is displayed.

The most notable benefit introduced by this mode it does not prevent merging
new code while allowing developer to address historical violation at his own
speed.

CI/CD
-----

If execution under `Github Actions`_ is detected via the presence of
``GITHUB_ACTIONS=true`` and ``GITHUB_WORFLOW=...`` variables, the linter will
also print errors using their `annotation`_ format.

.. _GitHub Actions: https://github.com/features/actions
.. _annotation: https://docs.github.com/en/actions/reference/workflow-commands-for-github-actions#setting-an-error-message

Linting Playbooks and Roles
---------------------------

It's important to note that ``ansible-lint`` accepts a list of Ansible playbook files or a list of role directories. Starting from a directory that contains the following, the playbook file, ``playbook.yml``, or one of the role subdirectories, such as ``geerlingguy.apache``, can be passed:

.. code-block::

  playbook.yml
  roles/
      geerlingguy.apache/
          tasks/
          handlers/
          files/
          templates/
          vars/
          defaults/
          meta/
      geerlingguy.elasticsearch/
          tasks/
          handlers/
          files/
          templates/
          vars/
          defaults/
          meta/

The following lints the role ``geerlingguy.apache``:

.. code-block::

    $ ansible-lint geerlingguy.apache

    [305] Use shell only when shell functionality is required
    /Users/chouseknecht/.ansible/roles/geerlingguy.apache/tasks/main.yml:19
    Task/Handler: Get installed version of Apache.

    [502] All tasks should be named
    /Users/chouseknecht/.ansible/roles/geerlingguy.apache/tasks/main.yml:29
    Task/Handler: include_vars apache-22.yml

    [502] All tasks should be named
    /Users/chouseknecht/.ansible/roles/geerlingguy.apache/tasks/main.yml:32
    Task/Handler: include_vars apache-24.yml

Here's the contents of ``playbook.yml``, which references multiples roles:

.. code-block:: yaml

  - name: Lint multiple roles
    hosts: all
    tasks:

    - include_role:
      name: geerlingguy.apache

    - include_role:
      name: geerlingguy.elasticsearch

The following lints ``playbook.yml``, which evaluates both the playbook and the referenced roles:

.. code-block::

    $ ansible-lint playbook.yml

    [305] Use shell only when shell functionality is required
    /Users/chouseknecht/roles/geerlingguy.apache/tasks/main.yml:19
    Task/Handler: Get installed version of Apache.

    [502] All tasks should be named
    /Users/chouseknecht/roles/geerlingguy.apache/tasks/main.yml:29
    Task/Handler: include_vars apache-22.yml

    [502] All tasks should be named
    /Users/chouseknecht/roles/geerlingguy.apache/tasks/main.yml:32
    Task/Handler: include_vars apache-24.yml

    [502] All tasks should be named
    /Users/chouseknecht/roles/geerlingguy.elasticsearch/tasks/main.yml:17
    Task/Handler: service state=started name=elasticsearch enabled=yes

Since ``ansible-lint`` accepts a list of roles or playbooks, the following works as well, producing the same output as the example above:

.. code-block::

    $ ansible-lint geerlingguy.apache geerlingguy.elasticsearch

    [305] Use shell only when shell functionality is required
    /Users/chouseknecht/roles/geerlingguy.apache/tasks/main.yml:19
    Task/Handler: Get installed version of Apache.

    [502] All tasks should be named
    /Users/chouseknecht/roles/geerlingguy.apache/tasks/main.yml:29
    Task/Handler: include_vars apache-22.yml

    [502] All tasks should be named
    /Users/chouseknecht/roles/geerlingguy.apache/tasks/main.yml:32
    Task/Handler: include_vars apache-24.yml

    [502] All tasks should be named
    /Users/chouseknecht/roles/geerlingguy.elasticsearch/tasks/main.yml:17
    Task/Handler: service state=started name=elasticsearch enabled=yes

Examples
--------

Included in ``ansible-lint/examples`` are some example playbooks with undesirable features. Running ansible-lint on them works, as demonstrated in the following:

.. code-block::

    $ ansible-lint examples/example.yml

    [301] Commands should not change things if nothing needs doing
    examples/example.yml:9
    Task/Handler: unset variable

    [206] Variables should have spaces before and after: {{ var_name }}
    examples/example.yml:10
        action: command echo {{thisvariable}} is not set in this playbook

    [301] Commands should not change things if nothing needs doing
    examples/example.yml:12
    Task/Handler: trailing whitespace

    [201] Trailing whitespace
    examples/example.yml:13
        action: command echo do nothing

    [401] Git checkouts must contain explicit version
    examples/example.yml:15
    Task/Handler: git check

    [401] Git checkouts must contain explicit version
    examples/example.yml:18
    Task/Handler: git check 2

    [301] Commands should not change things if nothing needs doing
    examples/example.yml:24
    Task/Handler: executing git through command

    [303] git used in place of git module
    examples/example.yml:24
    Task/Handler: executing git through command

    [303] git used in place of git module
    examples/example.yml:27
    Task/Handler: executing git through command

    [401] Git checkouts must contain explicit version
    examples/example.yml:30
    Task/Handler: using git module

    [206] Variables should have spaces before and after: {{ var_name }}
    examples/example.yml:34
        action: debug msg="{{item}}"

    [201] Trailing whitespace
    examples/example.yml:35
        with_items:

    [403] Package installs should not use latest
    examples/example.yml:39
    Task/Handler: yum latest

    [403] Package installs should not use latest
    examples/example.yml:44
    Task/Handler: apt latest

    [101] Deprecated always_run
    examples/example.yml:47
    Task/Handler: always run


If playbooks include other playbooks, or tasks, or handlers or roles, these are also handled:

.. code-block::

    $ ansible-lint examples/include.yml

    [301] Commands should not change things if nothing needs doing
    examples/play.yml:5
    Task/Handler: a bad play

    [303] service used in place of service module
    examples/play.yml:5
    Task/Handler: a bad play

    [401] Git checkouts must contain explicit version
    examples/roles/bobbins/tasks/main.yml:2
    Task/Handler: test tasks

    [701] No 'galaxy_info' found
    examples/roles/hello/meta/main.yml:1
    {'meta/main.yml': {'dependencies': [{'role': 'bobbins', '__line__': 3, '__file__': '/Users/akx/build/ansible-lint/examples/roles/hello/meta/main.yml'}], '__line__': 1, '__file__': '/Users/akx/build/ansible-lint/examples/roles/hello/meta/main.yml', 'skipped_rules': []}}

    [303] service used in place of service module
    examples/roles/morecomplex/handlers/main.yml:1
    Task/Handler: restart service using command

    [301] Commands should not change things if nothing needs doing
    examples/roles/morecomplex/tasks/main.yml:1
    Task/Handler: test bad command

    [302] mkdir used in place of argument state=directory to file module
    examples/roles/morecomplex/tasks/main.yml:1
    Task/Handler: test bad command

    [301] Commands should not change things if nothing needs doing
    examples/roles/morecomplex/tasks/main.yml:4
    Task/Handler: test bad command v2

    [302] mkdir used in place of argument state=directory to file module
    examples/roles/morecomplex/tasks/main.yml:4
    Task/Handler: test bad command v2

    [301] Commands should not change things if nothing needs doing
    examples/roles/morecomplex/tasks/main.yml:7
    Task/Handler: test bad local command

    [305] Use shell only when shell functionality is required
    examples/roles/morecomplex/tasks/main.yml:7
    Task/Handler: test bad local command

    [504] Do not use 'local_action', use 'delegate_to: localhost'
    examples/roles/morecomplex/tasks/main.yml:8
      local_action: shell touch foo

    [201] Trailing whitespace
    examples/tasks/x.yml:3
      args:

    [201] Trailing whitespace
    examples/tasks/x.yml:3
      args:

.. usage-docs-inclusion-marker-end-do-not-remove

Configuring
===========

.. configuring-docs-inclusion-marker-do-not-remove

Configuration File
------------------

Ansible-lint supports local configuration via a ``.ansible-lint`` configuration file. Ansible-lint checks the working directory for the presence of this file and applies any configuration found there. The configuration file location can also be overridden via the ``-c path/to/file`` CLI flag.

If a value is provided on both the command line and via a config file, the values will be merged (if a list like **exclude_paths**), or the **True** value will be preferred, in the case of something like **quiet**.

The following values are supported, and function identically to their CLI counterparts:

.. code-block:: yaml

    exclude_paths:
      - ./my/excluded/directory/
      - ./my/other/excluded/directory/
      - ./last/excluded/directory/
    parseable: true
    quiet: true
    rulesdir:
      - ./rule/directory/
    skip_list:
      - skip_this_tag
      - and_this_one_too
      - skip_this_id
      - '401'
    tags:
      - run_this_tag
    use_default_rules: true
    verbosity: 1


Pre-commit Setup
----------------

To use ansible-lint with `pre-commit`_, just add the following to your local repo's ``.pre-commit-config.yaml`` file. Make sure to change **rev:** to be either a git commit sha or tag of ansible-lint containing ``hooks.yaml``.

.. code-block:: yaml

    - repo: https://github.com/ansible/ansible-lint.git
      rev: v4.1.0
      hooks:
        - id: ansible-lint
          files: \.(yaml|yml)$

.. _pre-commit: https://pre-commit.com

.. configuring-docs-inclusion-marker-end-do-not-remove

Rules
=====

.. rules-docs-inclusion-marker-do-not-remove

Specifying Rules at Runtime
---------------------------

By default, ``ansible-lint`` uses the rules found in ``ansible-lint/lib/ansiblelint/rules``. To override this behavior and use a custom set of rules, use the ``-r /path/to/custom-rules`` option to provide a directory path containing the custom rules. For multiple rule sets, pass multiple ``-r`` options.

It's also possible to use the default rules, plus custom rules. This can be done by passing the ``-R`` to indicate that the default rules are to be used, along with one or more ``-r`` options.

Using Tags to Include Rules
```````````````````````````

Each rule has an associated set of one or more tags. To view the list of tags for each available rule, use the ``-T`` option.

The following shows the available tags in an example set of rules, and the rules associated with each tag:

.. code-block:: bash

    $ ansible-lint -v -T

    behaviour ['[503]']
    bug ['[304]']
    command-shell ['[305]', '[302]', '[304]', '[306]', '[301]', '[303]']
    deprecated ['[105]', '[104]', '[103]', '[101]', '[102]']
    formatting ['[104]', '[203]', '[201]', '[204]', '[206]', '[205]', '[202]']
    idempotency ['[301]']
    idiom ['[601]', '[602]']
    metadata ['[701]', '[704]', '[703]', '[702]']
    module ['[404]', '[401]', '[403]', '[402]']
    oddity ['[501]']
    readability ['[502]']
    repeatability ['[401]', '[403]', '[402]']
    resources ['[302]', '[303]']
    safety ['[305]']
    task ['[502]', '[503]', '[504]', '[501]']

To run just the *idempotency* rules, for example, run the following:

.. code-block:: bash

    $ ansible-lint -t idempotency playbook.yml

Excluding Rules
```````````````

To exclude rules from the available set of rules, use the ``-x SKIP_LIST`` option. For example, the following runs all of the rules except those with the tags *readability* and *safety*:

.. code-block:: bash

    $ ansible-lint -x readability,safety playbook.yml

It's also possible to skip specific rules by passing the rule ID. For example, the following excludes rule *502*:

.. code-block:: bash

    $ ansible-lint -x 502 playbook.yml

False Positives: Skipping Rules
-------------------------------

Some rules are a bit of a rule of thumb. Advanced *git*, *yum* or *apt* usage, for example, is typically difficult to achieve through the modules. In this case, you should mark the task so that warnings aren't produced.

To skip a specific rule for a specific task, inside your ansible yaml add ``# noqa [rule_id]`` at the end of the line. If the rule is task-based (most are), add at the end of any line in the task. You can skip multiple rules via a space-separated list.

.. code-block:: yaml

    - name: this would typically fire GitHasVersionRule 401 and BecomeUserWithoutBecomeRule 501
      become_user: alice  # noqa 401 501
      git: src=/path/to/git/repo dest=checkout

If the rule is line-based, ``# noqa [rule_id]`` must be at the end of the particular line to be skipped

.. code-block:: yaml

    - name: this would typically fire LineTooLongRule 204 and VariableHasSpacesRule 206
      get_url:
        url: http://example.com/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/really_long_path/file.conf  # noqa 204
        dest: "{{dest_proj_path}}/foo.conf"  # noqa 206


It's also a good practice to comment the reasons why a task is being skipped.

If you want skip running a rule entirely, you can use either use ``-x`` command
line argument, or add it to ``skip_list`` inside the configuration file.

A less-preferred method of skipping is to skip all task-based rules for a task (this does not skip line-based rules). There are two mechanisms for this: the ``skip_ansible_lint`` tag works with all tasks, and the ``warn`` parameter works with the *command* or *shell* modules only. Examples:

.. code-block:: yaml

    - name: this would typically fire CommandsInsteadOfArgumentRule 302
      command: warn=no chmod 644 X

    - name: this would typically fire CommandsInsteadOfModuleRule 303
      command: git pull --rebase
      args:
        warn: False

    - name: this would typically fire GitHasVersionRule 401
      git: src=/path/to/git/repo dest=checkout
      tags:
      - skip_ansible_lint

Creating Custom Rules
---------------------

Rules are described using a class file per rule. Default rules are named *DeprecatedVariableRule.py*, etc.

Each rule definition should have the following:

* ID: A unique identifier
* Short description: Brief description of the rule
* Description: Behaviour the rule is looking for
* Tags: one or more tags that may be used to include or exclude the rule
* At least one of the following methods:

  * ``match`` that takes a line and returns None or False, if the line doesn't match the test, and True or a custom message, when it does. (This allows one rule to test multiple behaviours - see e.g. the *CommandsInsteadOfModulesRule*.)
  * ``matchtask`` that operates on a single task or handler, such that tasks get standardized to always contain a *module* key and *module_arguments* key. Other common task modifiers, such as *when*, *with_items*, etc., are also available as keys, if present in the task.

An example rule using ``match`` is:

.. code-block:: python

    from ansiblelint.rules import AnsibleLintRule

    class DeprecatedVariableRule(AnsibleLintRule):

        id = 'EXAMPLE002'
        shortdesc = 'Deprecated variable declarations'
        description = 'Check for lines that have old style ${var} ' + \
                      'declarations'
        tags = { 'deprecated' }

        def match(self, file, line):
            return '${' in line

An example rule using ``matchtask`` is:

.. code-block:: python

    import ansiblelint.utils
    from ansiblelint.rules import AnsibleLintRule

    class TaskHasTag(AnsibleLintRule):
        id = 'EXAMPLE001'
        shortdesc = 'Tasks must have tag'
        description = 'Tasks must have tag'
        tags = ['productivity']

        def matchtask(self, file, task):
            # If the task include another task or make the playbook fail
            # Don't force to have a tag
            if not set(task.keys()).isdisjoint(['include','fail']):
                return False

            # Task should have tags
            if not task.has_key('tags'):
                  return True

        return False

The task argument to ``matchtask`` contains a number of keys - the critical one is *action*. The value of *task['action']* contains the module being used, and the arguments passed, both as key-value pairs and a list of other arguments (e.g. the command used with shell).

In ansible-lint 2.0.0, *task['action']['args']* was renamed *task['action']['module_arguments']* to avoid a clash when a module actually takes args as a parameter key (e.g. ec2_tag)

In ansible-lint 3.0.0 *task['action']['module']* was renamed *task['action']['__ansible_module__']* to avoid a clash when a module take module as an argument. As a precaution, *task['action']['module_arguments']* was renamed *task['action']['__ansible_arguments__']*.

Packaging Custom Rules
``````````````````````

Ansible-lint provides a sub directory named *custom* in its built-in rules,
``/usr/lib/python3.8/site-packages/ansiblelint/rules/custom/`` for example, to
install custom rules since v4.3.1. The custom rules which are packaged as an
usual python package installed into this directory will be loaded and enabled
automatically by ansible-lint.

To make custom rules loaded automatically, you need the followings:

- Packaging your custom rules as an usual python package named some descriptive ones like ``ansible_lint_custom_rules_foo``.
- Make it installed into ``<ansible_lint_custom_rules_dir>/custom/<your_custom_rules_subdir>/``.

You may accomplish the second by adding some configurations into the [options]
section of the ``setup.cfg`` of your custom rules python package like the following.

.. code-block::

    [options]
    packages =
        ansiblelint.rules.custom.<your_custom_rules_subdir>
    package_dir =
        ansiblelint.rules.custom.<your_custom_rules_subdir> = <your_rules_source_code_subdir>

.. rules-docs-inclusion-marker-end-do-not-remove

Contributing
============

Please read `Contribution guidelines`_ if you wish to contribute.

Authors
=======

ansible-lint was created by `Will Thames`_ and is now maintained as part of the `Ansible`_ by `Red Hat`_ project.

.. _Contribution guidelines: https://ansible-lint.readthedocs.io/en/latest/contributing.html
.. _Will Thames: https://github.com/willthames
.. _Ansible: https://ansible.com
.. _Red Hat: https://redhat.com