Introduction

Ansible is a versatile automation tool that simplifies IT operations and infrastructure management. One of its powerful features is the ability to interact with source control repositories. To ensure predictable and consistent behavior, Ansible provides various rules to guide playbook development. In this article, we will explore Rule 401, specifically focused on Git repositories, known as "latest[git] in [Ansible-Lint](/articles/ansible-lint). We will delve into the significance of this rule and how it helps maintain a stable and reproducible workflow in Ansible playbooks.

Understanding Rule 401 - "latest[git]"

Rule 401, also referred to as "latest[git]," is a part of Ansible's extensive rule set designed to ensure best practices in playbook development. This rule primarily checks module arguments related to source control checkouts, specifically Git repositories. Its main objective is to identify arguments that might introduce variability or unpredictability based on the context in which they are executed.

The latest rule serves as a replacement for two older rules, "git-latest" and "hg-latest." By consolidating these rules into a more generic "latest," Ansible promotes consistency and reliability when interacting with Git repositories.

Problematic Code

Let's examine a problematic code snippet that Rule 401, "latest[git]," can identify in your playbooks:

``yaml

---

  • name: Example for latest rule

hosts: all

tasks:

- name: Risky use of git module

ansible.builtin.git:

repo: "https://github.com/ansible/ansible-lint"

version: HEAD # <-- HEAD value is triggering the rule

`

In this code, the playbook uses "HEAD" as the value for the version argument in the Git module. Using "HEAD" can lead to unpredictability, as it fetches the latest commit on the default branch, which may change over time.

Output:

`bash

WARNING Listing 1 violation(s) that are fatal

latest[git]: Result of the command may vary on subsequent runs.

401.yml:5 Task/Handler: Risky use of git module

Read documentation for instructions on how to ignore specific rule violations.

Rule Violation Summary

count tag profile rule associated tags

1 latest[git] safety idempotency

Failed: 1 failure(s), 0 warning(s) on 1 files. Last profile that met the validation criteria was 'moderate'. Rating: 2/5 star

`

Correct Code

The corrected code that aligns with Rule 401 is as follows:

`yaml

---

  • name: Example for latest rule

hosts: all

tasks:

- name: Safe use of git module

ansible.builtin.git:

repo: "https://github.com/ansible/ansible-lint"

version: abcd1234... # <-- that is safe

`

In the improved version, the playbook uses a specific commit hash (e.g., "abcd1234`...") for the version argument in the Git module. This ensures that a consistent and known version is checked out from the repository, making the playbook mo