Exercise: Git and development containers

Git and Development Containers

• Clone a project and fix its lint findings in the development container.
• Record the development container and execution environment in the project.
• Run the project in an execution environment and verify the result.
• Commit and push the work, without generated files.

Prerequisites: Complete both exercises in this chapter. The two container images from the previous exercise should already be on workstation. Run commands as student on workstation.

From ~/workflow-review, run:

lab grade workflow-review

The grader checks the clone, runs ansible-lint in the development container, checks that everything is committed and pushed (including both settings files), and checks the status page on serverb.

Add a README.md section that explains how to open the project in VS Code and how to run it. Commit and push it, then clone the remote into a temporary directory and check that a fresh clone contains everything a new colleague needs.

Clone the shared web-status project into ~/workflow-review and make it ready for the team.

• site.yml must pass ansible-lint in the development container, without disabling any rule.
• The project must contain .devcontainer/devcontainer.json for the development container image with the Ansible extension, and an ansible-navigator.yml that runs playbooks in ghcr.io/ansible-community/community-ee-minimal:latest, with standard output and no playbook artifacts.
• Running the project from its execution environment must leave Apache running and enabled on serverb, serving the status page.
• Commit and push all of this. ansible-navigator.log must never be committed. Finish with a clean working tree that matches the remote.

Clone the project

Start the exercise and clone the remote into the empty project directory. Look at the history and the files.

[student@workstation ~]$ lab start workflow-review
[student@workstation ~]$ cd ~/workflow-review
[student@workstation workflow-review]$ git clone ~/git-repos/ops/web-status.git .
[student@workstation workflow-review]$ git log --oneline
[student@workstation workflow-review]$ ls
ansible.cfg  inventory  README.md  site.yml  templates

Fix the lint findings

Run ansible-lint in the development container and fix every finding.

[student@workstation workflow-review]$ podman run --rm --security-opt label=disable \
  -v "$PWD:/workdir" -w /workdir \
  ghcr.io/ansible/community-ansible-dev-tools:latest ansible-lint site.yml
...output omitted...
fqcn[action-core]: Use FQCN for builtin module actions (dnf).
site.yml:6:7 Use `ansible.builtin.dnf` or `ansible.legacy.dnf` instead.

yaml[octal-values]: Forbidden implicit octal value "0644"
site.yml:14

yaml[truthy]: Truthy value should be one of [false, true]
site.yml:20

Change dnf: to ansible.builtin.dnf:, quote the mode as mode: "0644", and change enabled: yes to enabled: true. Run the linter again until it reports Passed.

---
- name: Status page is published
  hosts: web
  tasks:
    - name: Web server is installed
      ansible.builtin.dnf:
        name: httpd
        state: present

    - name: Status page is deployed
      ansible.builtin.template:
        src: templates/index.html.j2
        dest: /var/www/html/index.html
        mode: "0644"

    - name: Web server is running
      ansible.builtin.service:
        name: httpd
        state: started
        enabled: true

Record the project's tools

Add the development container settings, the navigator settings and a .gitignore for the navigator log.

Create .devcontainer/devcontainer.json and ansible-navigator.yml with the same content as in the previous exercise, then:

ansible-navigator.log

Run and verify

Run the project with ansible-navigator, twice, and check the page on serverb.

[student@workstation workflow-review]$ ansible-navigator run site.yml
...output omitted...
serverb.lab.example.com    : ok=4    changed=3    unreachable=0    failed=0  ...
[student@workstation workflow-review]$ ansible-navigator run site.yml
...output omitted...
serverb.lab.example.com    : ok=4    changed=0    unreachable=0    failed=0  ...
[student@workstation workflow-review]$ ssh devops@serverb.lab.example.com curl -s localhost
<h1>Status: serverb.lab.example.com</h1>
<p>Deployed from Git.</p>

Commit, push and grade

Review what you are about to commit, commit it with a clear message, push it, and grade.

[student@workstation workflow-review]$ git status --short
 M site.yml
?? .devcontainer/
?? .gitignore
?? ansible-navigator.yml
[student@workstation workflow-review]$ git add -A
[student@workstation workflow-review]$ git diff --cached --stat
[student@workstation workflow-review]$ git commit -m 'Fix lint findings and record the project tools'
[student@workstation workflow-review]$ git push
[student@workstation workflow-review]$ git status
On branch main
Your branch is up to date with 'origin/main'.

nothing to commit, working tree clean
[student@workstation workflow-review]$ lab grade workflow-review

ansible-navigator.log is on disk but not in git status, because .gitignore lists it. When you are done, run lab finish workflow-review.