feat(blog): add forgejo runner article

2025-04-08 21:24:57 +02:00 · 2025-04-08 21:24:57 +02:00 · c6ecfe0d34
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+---
+title: 'Deploying a forgejo runner with ansible'
+description: 'Some ansible code and a golden rule'
+date: '2025-04-08'
+tags:
+- 'ansible'
+- 'forgejo'
+---
+
+## Introduction
+
+After [migrating my git.adyxax.org to forgejo]({{< ref "forgejo.md" >}}) a few
+weeks back, I started experimenting with their CI offering: forgejo actions. It
+is mostly a clone of GitHub actions, which means it is a mixed bag.
+
+I am still relying on [eventline](https://www.exograd.com/products/eventline)
+for all the important stuff I manage, but I wanted to get the actions
+integration for some simple and non consequential CI jobs.
+
+## The good and the bad
+
+The good part is obviously the tight integration with forgejo's UI. Forgejo (or
+gitea which forgejo forked from) developers also made the great decision of
+adding runners dedicated to individual users, which allows me to open my forgejo
+instance to other people without offering them access to a runner.
+
+The bad part all has to do with trying to be a GitHub actions clone:
+- The reliance on nodejs actions for everything.
+- The non case sensitivity in weird places (the most damning example in my eyes
+  being `if: ${{ github.ref == 'refs/heads/main' }}` which looks like an
+  equality check, but it will match any case variation of `MaIn`).
+- It is YAML soup, and workflow reuse is clunky at best.
+
+## The golden rule
+
+I find that the following golden rule applies to all CIs: avoid building any
+actual logic into your workflows outside of the simple orchestration of the
+tasks. [Here is an
+example](https://git.adyxax.org/adyxax/www/src/branch/main/.forgejo/workflows/main.yaml)
+workflow that illustrates this rule.
+
+As you can see, I use simple (and often one liner) build, test or deploy
+commands that call a Makefile to do the heavy lifting. This guarantees that I am
+always able to build or deploy locally as well as debug more easily my
+workflows.
+
+## Making do without the runner containers
+
+I greatly dislike the default forgejo runner containers: They package everything
+and the kitchen sink, which is necessary given how clunky the whole nodejs
+ecosystem is (which the actions rely on).
+
+Fortunately I can do without these runner containers. The documentation will
+warn about its dangers and I caution you too if you plan to follow in my
+footsteps: You need to manage the proper isolation yourself and take care of not
+making a mess of the host operating system!
+
+Managing the proper isolation is not hard: instead of letting forgejo runner
+spawn its own containers, I myself run it constrained inside either a container
+or a jail.
+
+Not making a mess of the host operating system requires discipline though
+because the runner environment does not get cleaned on each run. Since I write
+my workflows and actions myself and follow the previously mentioned golden rule,
+with some discipline and experience I make it work.
+
+## Ansible role
+
+### Tasks
+
+Here is an example `tasks.yaml` that deploys the forgejo runner on a Debian
+system. It does not configure the runner itself, that I do manually once after
+the first deployment.
+
+``` yaml
+---
+- name: 'Install forgejo-runner dependencies'
+  package:
+    name:
+      - 'git-crypt'
+      - 'hugo'
+      - 'nodejs'
+
+- name: 'Download forgejo runner {{ versions.forgejo_runner.tag }}'
+  get_url:
+    url: 'https://code.forgejo.org/forgejo/runner/releases/download/v{{ versions.forgejo_runner.tag }}/forgejo-runner-{{ versions.forgejo_runner.tag }}-linux-amd64'
+    dest: '/usr/local/bin/forgejo-runner'
+    mode: '0555'
+  notify: 'restart forgejo runner'
+
+- name: 'Create forgejo-runner group on server'
+  group:
+    name: 'forgejo-runner'
+    system: 'yes'
+
+- name: 'Create forgejo-runner user on server'
+  user:
+    name: 'forgejo-runner'
+    group: 'forgejo-runner'
+    shell: '/bin/sh'
+    home: '/srv/forgejo-runner'
+    createhome: 'yes'
+    system: 'yes'
+    password: '*'
+
+- name: 'Deploy forgejo systemd service unit'
+  copy:
+    src: 'forgejo-runner.service'
+    dest: '/etc/systemd/system/'
+    owner: 'root'
+    group: 'root'
+    mode: '0440'
+  notify: 'systemctl daemon-reload'
+
+- name: 'Start forgejo-runner and activate it on boot'
+  service:
+    name: 'forgejo-runner'
+    enabled: true
+    state: 'started'
+```
+
+### Handlers
+
+This role relies on two handlers:
+
+``` yaml
+---
+- name: 'restart forgejo runner'
+  service:
+    name: 'forgejo-runner'
+    state: 'restarted'
+
+- name: 'systemctl daemon-reload'
+  shell:
+    cmd: 'systemctl daemon-reload'
+```
+
+### Files
+
+Here is my `forgejo-runner.service` systemd unit file:
+
+``` ini
+###############################################################################
+#     \_o<     WARNING : This file is being managed by ansible!      >o_/     #
+#     ~~~~                                                           ~~~~     #
+###############################################################################
+[Unit]
+Description=Forgejo Runner
+Documentation=https://forgejo.org/docs/latest/admin/actions/
+After=network.target
+
+[Service]
+ExecStart=forgejo-runner daemon
+ExecReload=/bin/kill -s HUP $MAINPID
+User=forgejo-runner
+WorkingDirectory=/srv/forgejo-runner
+Restart=on-failure
+TimeoutSec=0
+RestartSec=10
+
+[Install]
+WantedBy=multi-user.target
+```
+
+### Manual runner registration
+
+There is an offline registration mechanism, but I did not attempt to use it.
+Since this is not an action I will redo often, I am content with running once:
+
+``` shell
+su - forgejo-runner
+forgejo-runner register
+               --instance https://git.adyxax.org \
+               --labels self-hosted:host://-self-hosted \
+               --name myth.adyxax.org \
+               --token XXXXXXXXXXX \
+               --no-interactive
+exit
+systemctl restart forgejo-runner
+```
+
+The registration token comes from my user settings page at
+https://git.adyxax.org/user/settings/actions/runners/.
+
+## Conclusion
+
+It works well, for now I am happy with it.