`Forgejo Actions` provides Continuous Integration driven from the files in the `.forgejo/workflows` directory of a repository, with a web interface to show the results. The syntax and semantics of the `workflow` files will be familiar to people used to [GitHub Actions](https://docs.github.com/en/actions) but **they are not and will never be identical**.
The following guide explains key **concepts** to help understand how `workflows` are interpreted, with a set of **examples** that can be copy/pasted and modified to fit particular use cases.
- Verify that `Enable Repository Actions` is checked in the `Repository` tab of the `/{owner}/{repository}/settings` page. If the checkbox does not show it means the administrator of the Forgejo instance did not activate the feature.
An `Action` is a repository that contains the equivalent of a function in any programming language. It comes in two flavors, depending on the file found at the root of the repository:
- **action.yml:** describes the inputs and outputs of the action and the implementation. See [this example](https://code.forgejo.org/actions/setup-forgejo/src/branch/main/action.yml).
- **Dockerfile:** if no `action.yml` file is found, it is used to create an image with `docker build` and run a container from it to carry out the action. See [this example](https://code.forgejo.org/forgejo/test-setup-forgejo-docker) and [the workflow that uses it](https://code.forgejo.org/actions/end-to-end/src/branch/main/actions/example-docker-action). Note that files written outside of the **workspace** will be lost when the **step** using such an action terminates.
One of the most commonly used action is [checkout](https://code.forgejo.org/actions/checkout#usage) which clones the repository that triggered a `workflow`. Another one is [setup-go](https://code.forgejo.org/actions/setup-go#usage) that will install Go.
Just as any other program of function, an `Action` has pre-requisites to successfully be installed and run. When looking at re-using an existing `Action`, this is an important consideration. For instance [setup-go](https://code.forgejo.org/actions/setup-go) depends on NodeJS during installation.
In a `workflow` file strings that look like `${{ ... }}` are evaluated by the `Forgejo runner` and are called expressions. As a shortcut, `if: ${{ ... }}` is equivalent to `if: ...`, i.e the `${{ }}` surrounding the expression is implicit and can be stripped. [Check out the example](https://code.forgejo.org/actions/end-to-end/src/branch/main/actions/example-expression/.forgejo/workflows/test.yml) that illustrates expressions.
-`contains( search, item )`. Returns `true` if `search` contains `item`. If `search` is an array, this function returns `true` if the `item` is an element in the array. If `search` is a string, this function returns `true` if the `item` is a substring of `search`. This function is not case sensitive. Casts values to a string.
-`startsWith( searchString, searchValue )`. Returns `true` when `searchString` starts with `searchValue`. This function is not case sensitive. Casts values to a string.
-`endsWith( searchString, searchValue )`. Returns `true` if `searchString` ends with `searchValue`. This function is not case sensitive. Casts values to a string.
-`format( string, replaceValue0, replaceValue1, ..., replaceValueN)`. Replaces values in the `string`, with the variable `replaceValueN`. Variables in the `string` are specified using the `{N}` syntax, where `N` is an integer. You must specify at least one `replaceValue` and `string`. Escape curly braces using double braces.
-`join( array, optionalSeparator )`. The value for `array` can be an array or a string. All values in `array` are concatenated into a string. If you provide `optionalSeparator`, it is inserted between the concatenated values. Otherwise, the default separator `,` is used. Casts values to a string.
-`toJSON(value)`. Returns a pretty-print JSON representation of `value`.
-`fromJSON(value)`. Returns a JSON object or JSON data type for `value`. You can use this function to provide a JSON object as an evaluated expression or to convert environment variables from a string.
PostgreSQL, redis and other services can be run from container images with something similar to the following. See also the [set of examples](https://code.forgejo.org/actions/end-to-end/src/branch/main/actions/example-service/.forgejo/workflows/).
A container with the specified `image:` is run before the `job` starts and is terminated when it completes. The job can address the service using its name, in this case `pgsql`.
The IP address of `pgsql` is on the same [docker network](https://docs.docker.com/engine/reference/commandline/network/) as the container running the **steps** and there is no need for port binding (see the [docker run --publish](https://docs.docker.com/engine/reference/commandline/run/) option for more information). The `postgres:15` image exposes the PostgreSQL port 5432 and a client will be able to connect as [shown in this example](https://code.forgejo.org/actions/end-to-end/src/branch/main/actions/example-service/.forgejo/workflows/postgresql.yml)
Key/value pairs injected in the environment when running the container, equivalent to [--env](https://docs.docker.com/engine/reference/commandline/run/).
A string of additional options, as documented [docker run](https://docs.docker.com/engine/reference/commandline/run/). For instance: "--workdir /myworkdir --ulimit nofile=1024:1024".
> **NOTE:** the `--volume` option is restricted to a whitelist of volumes configured in the runner executing the task. See the [Forgejo Actions administrator guide](../../admin/actions/) for more information.
`Forgejo` itself does not run the `jobs`, it relies on the [Forgejo runner](https://code.forgejo.org/forgejo/runner) to do so. See the [Forgejo Actions administrator guide](../../admin/actions/) for more information.
A `Forgejo runner` listens on a `Forgejo` instance, waiting for jobs. To figure out if a runner is available for a given repository, go to `/{owner}/{repository}/settings/actions/runners`. If there are none, you can run one for yourself on your laptop.
Some runners are **Global** and are available for every repository, others are only available for the repositories within a given user or organization. And there can even be runners dedicated to a single repository. The `Forgejo` administrator is the only one able to launch a **Global** runner. But the user who owns an organization can launch a runner without requiring any special permission. All they need to do is to get a runner registration token and install the runner on their own laptop or on a server of their choosing (see the [Forgejo Actions administrator guide](../../admin/actions/) for more information).
Following the link on a task displays the logs and the `Re-run all jobs` button. It is also possible to re-run a specific job by hovering on it and clicking on the arrows.
A repository, a user or an organization can hold secrets, a set of key/value pairs that are stored encrypted in the `Forgejo` database and revealed to the `workflows` as `${{ secrets.KEY }}`. They can be defined from the web interface:
A repository, a user or an organization can hold variables, a set of key/value pairs that are stored in the `Forgejo` database and available to the `workflows` as `${{ vars.KEY }}`. They can be defined from the web interface:
- in `/org/{org}/settings/actions/variables` to be available in all the repositories that belong to the organization
- in `/user/settings/actions/variables` to be available in all the repositories that belong to the logged in user
- in `/{owner}/{repo}/settings/actions/variables` to be available to the `workflows` of a single repository
Once the variable is added, its value cannot be changed.
The syntax and semantics of the YAML file describing a `workflow` are _partially_ explained here. When an entry is missing the [GitHub Actions](https://docs.github.com/en/actions) documentation may be helpful because there are similarities. But there also are significant differences that require testing.
Each `job` in a `workflow` must specify the kind of machine it needs to run its `steps` with `runs-on`. For instance `docker` in the following `workflow`:
The actual machine provided by the runner **entirely depends on how the `Forgejo runner` was registered** (see the [Forgejo Actions administrator guide](../../admin/actions/) for more information).
By default the `docker` label will create a container from a [Node.js 16 Debian GNU/Linux bullseye image](https://hub.docker.com/_/node/tags?name=16-bullseye) and will run each `step` as root. Since an application container is used, the jobs will inherit the limitations imposed by the engine (Docker for instance). In particular they will not be able to run or install software that depends on `systemd`.
The `runs-on: self-hosted` label will run the jobs in a [LXC](https://linuxcontainers.org/lxc/) container where software that rely on `systemd` can be installed. Nested containers can also be created recursively (see [the `setup-forgejo` integration tests](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/.forgejo/workflows/integration.yml) for an example).
If the default image is unsuitable, a job can specify an alternate container image with `container:`, [as shown in this example](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-container/.forgejo/workflows/test.yml). For instance the following will ensure the job is run using [Alpine 3.18](https://hub.docker.com/_/alpine/tags?name=3.18).
A string of additional options, as documented [docker run](https://docs.docker.com/engine/reference/commandline/run/). For instance: "--workdir /myworkdir --ulimit nofile=1024:1024".
> **NOTE:** the `--volume` option is restricted to a whitelist of volumes configured in the runner executing the task. See the [Forgejo Actions administrator guide](../../admin/actions/) for more information.
-`success()`. returns true when none of the previous steps have failed or been canceled.
-`always()`. causes the step to always execute, and returns true, even when canceled. If you want to run a job or step regardless of its success or failure, use the recommended alternative: **!cancelled()**.
-`failure()`. returns true when any previous step of a job fails.
Check out the workflows in [example-if](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-if/) and [example-if-fail](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-if-fail/).
A relative `Action` such as `uses: actions/checkout@v3` will clone the repository at the URL composed by prepending the default actions URL which is https://code.forgejo.org/. It is the equivalent of providing the fully qualified URL `uses: https://code.forgejo.org/actions/checkout@v3`. In other words the following:
> **NOTE:** the most common mistake when using an action included in the repository under test is to forget to checkout the repository with `uses: actions/checkout@v3`.
For remote actions that are implemented with a `Dockerfile` instead of `action.yml`, the `args` key is used as command line arguments when the container is run.
[checks/check and test] 🐳 docker run image=node:16-bullseye platform= entrypoint=["/bin/sleep" "10800"] cmd=[]
[checks/check and test] ☁ git clone 'https://code.forgejo.org/actions/setup-go' # ref=v3
[checks/check and test] ⭐ Run Main actions/setup-go@v3
[checks/check and test] 🐳 docker cp src=/home/loic/.cache/act/actions-setup-go@v3/ dst=/var/run/act/actions/actions-setup-go@v3/
...
|
| ==> Ok
|
[checks/check and test] ✅ Success - Main test
[checks/check and test] ⭐ Run Post actions/setup-go@v3
[checks/check and test] 🐳 docker exec cmd=[node /var/run/act/actions/actions-setup-go@v3/dist/cache-save/index.js] user= workdir=
[checks/check and test] ✅ Success - Post actions/setup-go@v3
[checks/check and test] Cleaning up services for job check and test
[checks/check and test] Cleaning up container for job check and test
[checks/check and test] Cleaning up network for job check and test, and network name is: FORGEJO-ACTIONS-TASK-push_WORKFLOW-checks_JOB-check-and-test-network
Each example is part of the [setup-forgejo](https://code.forgejo.org/forgejo/end-to-end/) action [test suite](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions). They can be run locally with something similar to:
- [Echo](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-echo/.forgejo/workflows/test.yml) - a single step that prints one sentence.
- [Expression](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-expression/.forgejo/workflows/test.yml) - a collection of various forms of expression.
- [Local actions](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-local-action/.forgejo) - using an action found in a directory instead of a remote repository.
- [PostgreSQL service](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-service/.forgejo/workflows/test.yml) - a PostgreSQL service and a connection to display the (empty) list of tables of the default database.
- [Using services](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-service/.forgejo/workflows/test.yml) - illustrates how to configure and use services.
- [Choosing the image with `container`](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-container/.forgejo/workflows/test.yml) - replacing the `runs-on: docker` image with the `alpine:3.18` image using `container:`.
- [Docker action](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-docker-action/.forgejo/workflows/test.yml) - using a action implemented as a `Dockerfile`.
- [`on.pull_request` and `on.pull_request_target` events](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-pull-request/.forgejo/workflows/test.yml).
- [Artifacts upload and download](https://code.forgejo.org/forgejo/end-to-end/src/branch/main/actions/example-artifacts/.forgejo/workflows/test.yml) - sharing files between `jobs`.
