Forgejo Actions administrator guide

Forgejo Actions provides continuous integration driven from the files found in the .forgejo/workflows directory of a repository.

Forgejo settings

Enabling

Forgejo Actions is still in alpha and disabled by default. It can be activated by adding the following to app.ini:

[actions]
ENABLED = true

Note that Forgejo does not run the jobs, it relies on the Forgejo runner to do so. It needs to be installed separately.

Default Actions URL

In a workflow, when uses: does not specify an absolute URL, the value of DEFAULT_ACTIONS_URL is prepended to it.

[actions]
ENABLED = true
DEFAULT_ACTIONS_URL = https://code.forgejo.org

The actions published at https://code.forgejo.org are:

  • known to work with Forgejo Actions
  • published under a Free Software license

They can be found in the following organizations:

When setting DEFAULT_ACTIONS_URL to a Forgejo instance with an open registration, care must be taken to avoid name conflicts. For instance if an action has uses: foo/bar@main it will clone and try to run the action found at DEFAULT_ACTIONS_URL/foo/bar if it exists, even if it provides something different than what is expected.

Forgejo runner

The Forgejo runner is a daemon that fetches workflows to run from a Forgejo instance, executes them, sends back with the logs and ultimately reports its success or failure.

Installation

Each Forgejo runner release is published for all supported architectures as:

Installation of the binary

Download the latest binary release and verify its signature:

$ wget -O forgejo-runner https://code.forgejo.org/forgejo/runner/releases/download/v3.0.0/forgejo-runner-3.0.0-linux-amd64
$ chmod +x forgejo-runner
$ wget -O forgejo-runner.asc https://code.forgejo.org/forgejo/runner/releases/download/v3.0.0/forgejo-runner-3.0.0-linux-amd64.asc
$ gpg --keyserver keys.openpgp.org --recv EB114F5E6C0DC2BCDD183550A4B61A2DC5923710
$ gpg --verify forgejo-runner.asc forgejo-runner
Good signature from "Forgejo <contact@forgejo.org>"
		aka "Forgejo Releases <release@forgejo.org>"

Installation of the OCI image

The OCI images are built from the Dockerfile which is found in the source directory. It contains the forgejo-runner binary.

$ docker run --rm code.forgejo.org/forgejo/runner:3.0.0 forgejo-runner --version
forgejo-runner version v3.0.0

It does not run as root:

$ docker run --rm code.forgejo.org/forgejo/runner:3.0.0 id
uid=1000 gid=1000 groups=1000

A docker-compose example is provided to demonstrate how to install that OCI image to successfully run a workflow.

Execution of the workflows

The Forgejo runner relies on application containers (Docker, Podman, etc) or system containers (LXC) to execute a workflow in an isolated environment. They need to be installed and configured independently.

  • Docker: See the Docker installation documentation for more information.

    IPv6 support is not enabled by default in docker. The following snippet enables this.

    virtualisation.docker = {
      daemon.settings = {
        fixed-cidr-v6 = "fd00::/80";
        ipv6 = true;
      };
    };
  • Podman: While Podman is generally compatible with Docker, it does not create a socket for managing containers by default (because it doesn’t usually need one).

    If the Forgejo runner complains about “daemon Docker Engine socket not found”, or “cannot ping the docker daemon”, you can use podman to provide a Docker compatible socket from an unprivileged user and pass that socket on to the runner, e.g. by executing:

    $ podman system service -t 0 &
    $ DOCKER_HOST=unix://${XDG_RUNTIME_DIR}/podman/podman.sock ./forgejo-runner daemon
  • LXC: For jobs to run in LXC containers, the Forgejo runner needs passwordless sudo access for all lxc-* commands on a Debian GNU/Linux bookworm system where LXC is installed. The LXC helpers can be used as follows to create a suitable container:

    $ git clone https://code.forgejo.org/forgejo/lxc-helpers
    $ sudo cp -a lxc-helpers/lxc-helpers{,-lib}.sh /usr/local/bin
    $ lxc-helpers.sh lxc_container_create myrunner
    $ lxc-helpers.sh lxc_container_start myrunner
    $ lxc-helpers.sh lxc_container_user_install forgejo-runners 1000 debian

    NOTE: Multiarch Go builds and binfmt need bookworm to produce and test binaries on a single machine for people who do not have access to dedicated hardware. If this is not needed, installing the Forgejo runner on bullseye will also work.

    The Forgejo runner can then be installed and run within the myrunner container.

    $ lxc-helpers.sh lxc_container_run forgejo-runners -- sudo --user debian bash
    $ sudo apt-get install docker.io wget gnupg2
    $ wget -O forgejo-runner https://code.forgejo.org/forgejo/runner/releases/download/v3.0.0/forgejo-runner-amd64
    ...

    Warning: LXC containers do not provide a level of security that makes them safe for potentially malicious users to run jobs. They provide an excellent isolation for jobs that may accidentally damage the system they run on.

Registration

The Forgejo runner needs to connect to a Forgejo instance and must be registered before doing so. It will give it permission to read the repositories and send back information to Forgejo such as the logs or its status.

  • Online registration A special kind of token is needed and can be obtained from the Create new runner button:

    • in /admin/actions/runners to accept workflows from all repositories.
    • in /org/{org}/settings/actions/runners to accept workflows from all repositories within the organization.
    • in /user/settings/actions/runners to accept workflows from all repositories of the logged in user
    • in /{owner}/{repository}/settings/actions/runners to accept workflows from a single repository.

    add a runner

    For instance, using a token obtained for a test repository from next.forgejo.org:

    forgejo-runner register --no-interactive --token {TOKEN} --name runner --instance https://next.forgejo.org --labels docker:docker://node:16-bullseye,self-hosted
    INFO Registering runner, arch=amd64, os=linux, version=3.0.0.
    INFO Runner registered successfully.

    It will create a .runner file that looks like:

    {
      "WARNING": "This file is automatically generated. Do not edit.",
      "id": 6,
      "uuid": "fcd0095a-291c-420c-9de7-965e2ebaa3e8",
      "name": "runner",
      "token": "{TOKEN}",
      "address": "https://next.forgejo.org",
      "labels": ["docker:docker://node:16-bullseye", "self-hosted"]
    }
  • Offline registration When Infrastructure as Code (Ansible, kubernetes, etc.) is used to deploy and configure both Forgejo and the Forgejo runner, it may be more convenient for it to generate a secret and share it with both.

    The forgejo forgejo-cli actions register --secret <secret> subcommand can be used to register the runner with the Forgejo instance and the forgejo-runner create-runner-file --secret <secret> subcommand can be used to configure the Forgejo runner with the credentials that will allow it to start picking up tasks from the Forgejo instances as soon as it comes online.

    For instance, on the machine running Forgejo:

    $ forgejo forgejo-cli actions register --name runner-name --scope myorganization \
    	  --labels docker \
    	  --secret 7c31591e8b67225a116d4a4519ea8e507e08f71f

    and on the machine on which the Forgejo runner is installed:

    $ forgejo-runner create-runner-file --instance https://example.conf \
    		 --secret 7c31591e8b67225a116d4a4519ea8e507e08f71f

    NOTE: the labels known to the runner are defined in the config.yml and MUST match the labels provided to the forgejo-cli actions register command above. In this example, labels: ['docker:docker://node:16-bullseye'] will tell the Forgejo runner that when a job specifies runs-on: docker, it will run in a container created from the node:16-bullseye image by default.

Configuration

The default configuration for the runner can be displayed with forgejo-runner generate-config, stored in a config.yml file, modified and used instead of the default with the --config flag.

$ forgejo-runner generate-config > config.yml
# Example configuration file, it's safe to copy this as the default config file without any modification.

log:
  # The level of logging, can be trace, debug, info, warn, error, fatal
  level: info

runner:
  # Where to store the registration result.
  file: .runner
  # Execute how many tasks concurrently at the same time.
  capacity: 1
  # Extra environment variables to run jobs.
  envs:
    A_TEST_ENV_NAME_1: a_test_env_value_1
    A_TEST_ENV_NAME_2: a_test_env_value_2
  # Extra environment variables to run jobs from a file.
  # It will be ignored if it's empty or the file doesn't exist.
  env_file: .env
  # The timeout for a job to be finished.
  # Please note that the Forgejo instance also has a timeout (3h by default) for the job.
  # So the job could be stopped by the Forgejo instance if it's timeout is shorter than this.
  timeout: 3h
  # Whether skip verifying the TLS certificate of the Forgejo instance.
  insecure: false
  # The timeout for fetching the job from the Forgejo instance.
  fetch_timeout: 5s
  # The interval for fetching the job from the Forgejo instance.
  fetch_interval: 2s
  # The labels of a runner are used to determine which jobs the runner can run, and how to run them.
  # Like: ["macos-arm64:host", "ubuntu-latest:docker://node:16-bullseye", "ubuntu-22.04:docker://node:16-bullseye"]
  # If it's empty when registering, it will ask for inputting labels.
  # If it's empty when execute `deamon`, will use labels in `.runner` file.
  labels: []

cache:
  # Enable cache server to use actions/cache.
  enabled: true
  # The directory to store the cache data.
  # If it's empty, the cache data will be stored in $HOME/.cache/actcache.
  dir: ""
  # The host of the cache server.
  # It's not for the address to listen, but the address to connect from job containers.
  # So 0.0.0.0 is a bad choice, leave it empty to detect automatically.
  host: ""
  # The port of the cache server.
  # 0 means to use a random available port.
  port: 0

container:
  # Specifies the network to which the container will connect.
  # Could be host, bridge or the name of a custom network.
  # If it's empty, create a network automatically.
  network: ""
  # Whether to use privileged mode or not when launching task containers (privileged mode is required for Docker-in-Docker).
  privileged: false
  # And other options to be used when the container is started (eg, --add-host=my.forgejo.url:host-gateway).
  options:
  # The parent directory of a job's working directory.
  # If it's empty, /workspace will be used.
  workdir_parent:
  # Volumes (including bind mounts) can be mounted to containers. Glob syntax is supported, see https://github.com/gobwas/glob
  # You can specify multiple volumes. If the sequence is empty, no volumes can be mounted.
  # For example, if you only allow containers to mount the `data` volume and all the json files in `/src`, you should change the config to:
  # valid_volumes:
  #   - data
  #   - /src/*.json
  # If you want to allow any volume, please use the following configuration:
  # valid_volumes:
  #   - '**'
  valid_volumes: []
  # overrides the docker client host with the specified one.
  # If it's empty, act_runner will find an available docker host automatically.
  # If it's "-", act_runner will find an available docker host automatically, but the docker host won't be mounted to the job containers and service containers.
  # If it's not empty or "-", the specified docker host will be used. An error will be returned if it doesn't work.
  docker_host: ""

host:
  # The parent directory of a job's working directory.
  # If it's empty, $HOME/.cache/act/ will be used.
  workdir_parent:

Cache configuration

Some actions such as https://code.forgejo.org/actions/cache or https://code.forgejo.org/actions/setup-go can communicate with the Forgejo runner to save and restore commonly used files such as compilation dependencies. They are stored as compressed tar archives, fetched when a job starts and saved when it completes.

If the machine has a fast disk, uploading the cache when the job starts may significantly reduce the bandwidth required to download and rebuild dependencies.

If the machine on which the Forgejo runner is running has a slow disk and plenty of CPU and bandwidth, it may be better to not activate the cache as it can slow down the execution time.

Running the daemon

Once the Forgejo runner is successfully registered, it can be run from the directory in which the .runner file is found with:

$ forgejo-runner daemon
INFO[0000] Starting runner daemon

To verify it is actually available for the targeted repository, go to /{owner}/{repository}/settings/actions/runners. It will show the runners:

  • dedicated to the repository with the repo type
  • available to all repositories within an organization or a user
  • available to all repositories, with the Global type

list the runners

Adding the .forgejo/workflows/demo.yaml file to the test repository:

on: [push]
jobs:
  test:
    runs-on: docker
    steps:
      - run: echo All Good

Will send a job request to the Forgejo runner that will display logs such as:

...
INFO[2023-05-28T18:54:53+02:00] task 29 repo is earl-warren/test https://code.forgejo.org https://next.forgejo.org
...
[/test] [DEBUG] Working directory '/workspace/earl-warren/test'
| All Good
[/test]   ✅  Success - Main echo All Good

It will also show a similar output in the Actions tab of the repository.

If no Forgejo runner is available, Forgejo will wait for one to connect and submit the job as soon as it is available.

Labels and runs-on

The workflows / tasks defined in the files found in .forgejo/workflows must specify the environment they need to run with runs-on. Each Forgejo runner declares with labels which one they support so Forgejo sends them tasks accordingly. For instance if a job within a workflow has:

runs-on: docker

it will be submitted to a runner that registered with a docker label (for instance with --labels docker:docker://node:16-bullseye).

  • Docker or Podman: If runs-on is matched to a label that contains docker://, the rest of it is interpreted as the default container image to use if no other is specified. The runner will execute all the steps, as root, within a container created from that image.
  • LXC: If runs-on is self-hosted, the runner will execute all the steps, as root, within a Debian GNU/Linux bullseye LXC container.

Packaging

NixOS

The forgejo-actions-runner recipe is released in NixOS.

Please note that the services.forgejo-actions-runner.instances.<name>.labels key may be set to [] (an empty list) to use the packaged Forgejo instance list. One of virtualisation.docker.enable or virtualisation.podman.enable will need to be set. The default Forgejo image list is populated with docker images.

Other runners

It is possible to use other runners instead of Forgejo runner. As long as they can connect to a Forgejo instance using the same protocol, they will be given tasks to run.