act_runner/README.md

# Gitea Runner

## Installation

### Prerequisites

Docker Engine Community version is required for docker mode. To install Docker CE, follow the official [install instructions](https://docs.docker.com/engine/install/).

### Download pre-built binary

Visit [here](https://dl.gitea.com/gitea-runner/) and download the right version for your platform.

### Build from source

```bash
make build
```

### Build a docker image

```bash
make docker
```

## Quickstart

Actions are disabled by default, so you need to add the following to the configuration file of your Gitea instance to enable it:

```ini
[actions]
ENABLED=true
```

### Register

```bash
./gitea-runner register
```

And you will be asked to input:

1. Gitea instance URL, like `http://192.168.8.8:3000/`. You should use your gitea instance ROOT_URL as the instance argument
 and you should not use `localhost` or `127.0.0.1` as instance IP;
2. Runner token, you can get it from `http://192.168.8.8:3000/admin/actions/runners`;
3. Runner name, you can just leave it blank;
4. Runner labels, you can just leave it blank.

The process looks like:

```text
INFO Registering runner, arch=amd64, os=darwin, version=0.1.5.
WARN Runner in user-mode.
INFO Enter the Gitea instance URL (for example, https://gitea.com/):
http://192.168.8.8:3000/
INFO Enter the runner token:
fe884e8027dc292970d4e0303fe82b14xxxxxxxx
INFO Enter the runner name (if set empty, use hostname: Test.local):

INFO Enter the runner labels, leave blank to use the default labels (comma-separated, for example, ubuntu-latest:docker://docker.gitea.com/runner-images:ubuntu-latest):

INFO Registering runner, name=Test.local, instance=http://192.168.8.8:3000/, labels=[ubuntu-latest:docker://docker.gitea.com/runner-images:ubuntu-latest ubuntu-22.04:docker://docker.gitea.com/runner-images:ubuntu-22.04 ubuntu-20.04:docker://docker.gitea.com/runner-images:ubuntu-20.04].
DEBU Successfully pinged the Gitea instance server
INFO Runner registered successfully.
```

You can also register with command line arguments.

```bash
./gitea-runner register --instance http://192.168.8.8:3000 --token <my_runner_token> --no-interactive
```

If the registry succeed, it will run immediately. Next time, you could run the runner directly.

### Run

```bash
./gitea-runner daemon
```

### Run with docker

```bash
docker run -e GITEA_INSTANCE_URL=https://your_gitea.com -e GITEA_RUNNER_REGISTRATION_TOKEN=<your_token> -v /var/run/docker.sock:/var/run/docker.sock --name my_runner gitea/runner:nightly
```

Mount a volume on `/data` if you want the registration file and optional config to survive container recreation (see [scripts/run.sh](scripts/run.sh)).

> **`/data` does not hold the image cache.** It is the runner's working directory and contains only the `.runner` registration file and, optionally, your config file. Images pulled for jobs live in the *Docker daemon's* data root, which for the `dind` flavours is inside the container (`/var/lib/docker`, or `/home/rootless/.local/share/docker` for `dind-rootless`). To keep the image cache across restarts, give that path its own volume as well — otherwise every new container re-pulls the job images. With the `basic` flavour the images live on whichever daemon you point the runner at, so there is nothing extra to persist.

### Image flavours

The image is published in three flavours, all built from the single multi-stage [Dockerfile](Dockerfile) in this repository. They differ only in how a Docker daemon is made available to the jobs the runner executes; the `gitea-runner` binary inside them is identical.

| Tag | Build target | Base image | Docker daemon | Process supervisor | Runs as |
| --- | --- | --- | --- | --- | --- |
| `latest` (and `<version>`) | `basic` | `alpine` | none — uses an external daemon you provide | [`tini`](https://github.com/krallin/tini) | `root` |
| `latest-dind` | `dind` | `docker:dind` | bundled, started inside the container | [`s6`](https://skarnet.org/software/s6/) | `root` (privileged) |
| `latest-dind-rootless` | `dind-rootless` | `docker:dind-rootless` | bundled, started rootless inside the container | [`s6`](https://skarnet.org/software/s6/) | `rootless` (UID 1000) |

#### `latest` — basic

The default flavour ships only the runner on a minimal Alpine base. It contains **no Docker daemon of its own**: jobs that use `docker://` images need a daemon supplied from outside the container, typically by bind-mounting the host's socket:

```bash
docker run -e GITEA_INSTANCE_URL=https://your_gitea.com -e GITEA_RUNNER_REGISTRATION_TOKEN=<your_token> \
  -v /var/run/docker.sock:/var/run/docker.sock --name my_runner gitea/runner:latest
```

`tini` is the entrypoint (it reaps zombie processes), and it just runs [`scripts/run.sh`](scripts/run.sh), which registers the runner on first start and then execs `gitea-runner daemon`. This flavour does not need `--privileged`. The trade-off is that jobs share the host's daemon, so they can see other containers and images on that daemon.

#### `latest-dind` — Docker-in-Docker

This flavour is based on the official `docker:dind` image and bundles its own Docker daemon, so it needs no external socket — only the `--privileged` flag that Docker-in-Docker requires:

```bash
docker run --privileged -e GITEA_INSTANCE_URL=https://your_gitea.com -e GITEA_RUNNER_REGISTRATION_TOKEN=<your_token> \
  --name my_runner gitea/runner:latest-dind
```

Two processes have to run side by side here (the Docker daemon and the runner), so the entrypoint is the [`s6`](https://skarnet.org/software/s6/) supervision tree under [`scripts/s6`](scripts/s6) instead of `tini`. `s6` starts `dockerd`, and the runner service waits for the daemon to come up (`s6-svwait`) before launching [`run.sh`](scripts/run.sh). Each container has a private daemon isolated from the host's, at the cost of running privileged.

#### `latest-dind-rootless` — rootless Docker-in-Docker

Same idea as `dind`, but built on `docker:dind-rootless` so the bundled daemon and the runner run as an unprivileged user (`rootless`, UID 1000) rather than `root`. `DOCKER_HOST` is preset to `unix:///run/user/1000/docker.sock` so the runner talks to the rootless daemon. This reduces the blast radius compared to the privileged `dind` flavour, but rootless Docker carries the usual rootless limitations (networking, cgroups, storage drivers, and some operations that need additional host configuration such as `/etc/subuid` / `/etc/subgid` mappings and unprivileged user-namespace support).

> **The UID is fixed at 1000.** It comes from the `rootless` user baked into the upstream `docker:dind-rootless` base image, and the bundled daemon always listens on `/run/user/1000/docker.sock` inside the container, so running this flavour as a different user (`--user 1001`) does not work. If you need the runner to talk to a *host* rootless daemon that runs under some other UID, use the `basic` flavour instead and bind-mount that daemon's socket (see [examples/vm/rootless-docker.md](examples/vm/rootless-docker.md)); pointing `DOCKER_HOST` at a host socket from inside `dind-rootless` will not work. Changing the UID otherwise means rebuilding the image from a base with a different `rootless` user.

> **Note on Podman:** these images target the Docker daemon. The bundled `dind`/`dind-rootless` daemons are `dockerd`, not Podman, and the `basic` flavour expects a Docker-compatible socket. Running them under rootless Podman is not a supported configuration, though pointing the `basic` flavour at a Podman socket that emulates the Docker API may work for some workloads.

### Configuration

The runner is configured with a YAML file. Generate a starting point (this matches what ships in the tree):

```bash
./gitea-runner generate-config > config.yaml
```

Pass it with `-c` / `--config` on any command that loads configuration (`register`, `daemon`, `cache-server`):

```bash
./gitea-runner -c config.yaml register
./gitea-runner -c config.yaml daemon
./gitea-runner -c config.yaml cache-server
```

Every option is described in [config.example.yaml](internal/pkg/config/config.example.yaml) (the same content `generate-config` prints).

#### Without a config file

If you omit `-c`, built-in defaults apply (same as an empty YAML document).

Earlier releases let a small set of environment variables (`GITEA_DEBUG`, `GITEA_TRACE`, `GITEA_RUNNER_CAPACITY`, `GITEA_RUNNER_FILE`, `GITEA_RUNNER_ENVIRON`, `GITEA_RUNNER_ENV_FILE`) override parts of the default config. Those overrides have been removed — use a YAML config file for all settings instead. For the Docker images, the entrypoint still understands a separate set of variables (such as `RUNNER_STATE_FILE`); see [scripts/run.sh](scripts/run.sh) and the container documentation below.

### Labels

Labels decide **which jobs a runner accepts** and **how it runs them**. A job's `runs-on` is matched against the runner's label names; the first match wins and selects the execution environment for that job.

A label is written as:

```text
<name>[:<schema>[:<args>]]
```

| Part | Meaning |
| --- | --- |
| `name` | The name a workflow refers to in `runs-on`, e.g. `ubuntu-latest`. |
| `schema` | Either `docker` or `host`. Defaults to `host` when omitted. |
| `args` | Only used by the `docker` schema: the image to run the job in. |

Two schemas are supported:

- **`docker://<image>`** — the job runs inside a container created from `<image>`:

  ```text
  ubuntu-latest:docker://docker.gitea.com/runner-images:ubuntu-latest
  ```

- **`host`** — the job's steps run directly on the machine the runner is on, using the tools installed there:

  ```text
  macos:host
  ```

So with the labels

```text
ubuntu-latest:docker://docker.gitea.com/runner-images:ubuntu-latest,macos:host
```

a workflow with `runs-on: ubuntu-latest` is executed in the `runner-images:ubuntu-latest` container, and one with `runs-on: macos` is executed directly on the host.

Names may themselves contain a colon (for example `pool:e57e18d4-10d4-406f-93bf-60f127221bdd`); only `host` and `docker` are treated as schemas.

If a job's `runs-on` matches none of the runner's labels, the job still runs, in the default `docker.gitea.com/runner-images:ubuntu-latest` image. Images maintained for this purpose are listed at [gitea/runner-images](https://gitea.com/gitea/runner-images).

Labels are chosen at registration time (`--labels`, or the interactive prompt) and can be changed afterwards by editing `runner.labels` in the config file, or in the Gitea UI under the runner's settings.

#### Registration vs config labels

If `runner.labels` is set in the YAML file, those labels are used during `register` and the `--labels` CLI flag is ignored.

The `daemon` command also accepts `--labels` (which defaults to the `GITEA_RUNNER_LABELS` environment variable), so the labels of an already registered runner can be changed without deleting its registration file. The most explicit source wins:

```
--labels / GITEA_RUNNER_LABELS   >   runner.labels in the config file   >   labels in the .runner file
```

Whenever the resulting labels differ from the ones in the registration file, they are written back to it and re-declared to the Gitea instance on startup.

> **Note:** A runner that only exposes `host` labels still needs access to a Docker daemon (e.g. a mounted `/var/run/docker.sock`) whenever a job uses a `docker://` action or a service container. `host` labels only change where the job's own steps run; container-based steps and actions are still executed with Docker.

#### Caching (`actions/cache`)

Each runner starts its own cache server automatically. Cache entries are local to that runner — runners do not share a cache by default.

**Shared cache across multiple runners**

Run one dedicated `gitea-runner cache-server` that all runners point at.

1. Create a config file for the cache server host:

   ```yaml
   cache:
     dir: /data/actcache
     port: 8088
     external_secret: "replace-with-a-strong-random-secret"
   ```

2. Start the server:

   ```bash
   gitea-runner -c cache-server-config.yaml cache-server
   ```

3. On every runner:

   ```yaml
   cache:
     external_server: "http://<cache-server-host>:8088/"
     external_secret: "replace-with-a-strong-random-secret"  # must match the server
   ```

Alternatively, mount the same NFS/CIFS share on every runner and point `cache.dir` at it — simpler, but with weaker isolation between repositories.

**S3 / MinIO** — mount object storage as a FUSE filesystem (e.g. [s3fs](https://github.com/s3fs-fuse/s3fs-fuse) or [goofys](https://github.com/kahing/goofys)) and set `cache.dir` to the mount point.

Flags `--dir`, `--host`, and `--port` on `cache-server` override the corresponding `cache.*` YAML keys; all other settings, including `external_secret`, require the config file.

#### Official Docker image

Besides `GITEA_INSTANCE_URL` and `GITEA_RUNNER_REGISTRATION_TOKEN`, the image entrypoint supports optional variables such as `CONFIG_FILE` (passed through as `-c`), `GITEA_RUNNER_LABELS`, `GITEA_RUNNER_EPHEMERAL`, `GITEA_RUNNER_ONCE`, `GITEA_RUNNER_NAME`, `GITEA_MAX_REG_ATTEMPTS`, `RUNNER_STATE_FILE`, and `GITEA_RUNNER_REGISTRATION_TOKEN_FILE`. See [scripts/run.sh](scripts/run.sh) for exact behavior.

For a fuller container-oriented walkthrough, see [examples/docker](examples/docker/README.md).

When `container.bind_workdir` is enabled, stale task workspace directories can be cleaned while the runner is idle:
- directories older than `runner.workdir_cleanup_age` are removed (default: `24h`; set `0` to disable)
- cleanup runs every `runner.idle_cleanup_interval` (default: `10m`; set `0` to disable)
- only purely numeric subdirectories under `container.workdir_parent` are treated as task workspaces and may be removed
- cleanup assumes `container.workdir_parent` is not shared across multiple runners

#### Post-task script (`runner.post_task_script`)

Optional host script that runs **after** each task's built-in cleanup (post-steps, container teardown, bind-workdir removal). Use it for extra machine housekeeping — Docker pruning, disk cleanup, and similar.

**While the script runs, the runner stops task heartbeats and stays offline from Gitea's perspective until the script exits (or hits `runner.post_task_script_timeout`, default `5m`).** A script that blocks without exiting keeps the runner from taking new work for up to that timeout. Script output goes to the runner log, not the job log; a non-zero exit is warned but does not change the job result.

On Windows, use `.exe`, `.bat`, or `.cmd` paths; **PowerShell (`.ps1`) is not supported yet** as the configured path — wrap commands in a `.cmd` file instead.

See **[docs/post-task-script.md](docs/post-task-script.md)** for lifecycle details, environment variables, timeout interaction, and platform notes.

### Example Deployments

Check out the [examples](examples) directory for sample deployment types.