Setup Erlang

This repository contains a JavaScript action to setup Erlang in your Github Actions workflows. It detects the platform of your runners and install a pre-built version of Erlang/OTP accordingly.

- uses: erlangsters/setup-erlang@v1
  with:
    erlang-version: 27
    install-rebar3: true

Additionally, you may also request the action to install the rebar3 script.

Binaries provenance

The pre-built binaries used by this action are the ones maintained by the Erlangsters community and therefore it supports Linux, macOS and Windows. See the Erlang builder for more information.

Basic usage

No input is required to use this action and therefore the most basic usage is the following.

- uses: erlangsters/setup-erlang@v1

It will simply use the latest version of Erlang/OTP and install just that.

Of course, you may specify an Erlang version with the erlang-version input field.

- uses: erlangsters/setup-erlang@v1
  with:
    erlang-version: 25

In this example, it will use the latest version 25.x that exists but you may give an even more specific version.

Advanced usage

There really is nothing more to this action other than the possibility to install the rebar3 script.

- uses: erlangsters/setup-erlang@v1
  with:
    install-rebar3: true

The install-rebar3 input field is optional and defaults to false.

Supported platforms

Like stated, it does not build Erlang and instead use pre-built binaries that are provided by the Erlangsters community. That implies that the supported platforms derived from their policy.

Erlang versions are available starting from version 25.x and are built for the following combination of OSes and architectures.

• Linux (amd64|arm64, glibc|musl)
• macOS (arm64)
• Windows (amd64)

If you're confused about what "glibc" and "musl" are, they are the C libraries used system-wide. Most Linux distros use the "GNU C Library"; however, distros like Alpine use musl, which has a smaller footprint.

XXX: Current limitation of Github is that the Alpine ARM64 will not accept JavaScript actions. Until it's supported, this action cannot support Linux arm64/musl.

Dummy applications

What's with the dummy-release/ and dummy-escript/ folders in this repository? Well, they're real-life Erlang applications that are used by the Github Actions workflow to test the setup-erlang action against them.

The dummy-release/ folder contains an OTP release which uses the popular cowboy framework to implement a basic HTTP server that runs locally. It exposes the /hello endpoint which takes a "name" and will reply with "Hello <name>!".

The dummy-escript/ folder on the other side contains an Erlang script, or "escript", that uses the popular gun library to make a HTTP request to that previous /hello endpoint. It takes the name as argument.

You got it, they're meant to be used together to test if the applications not only build successfully, but also runs flawlessly (after they're distributed, on a different machine).

More examples

Distributing cross-platform Erlang applications can be a pain. That's why setting up proper CI/CD from the start of your project is important.

To help with this task, you can consult those examples which use this Github action, and get inspiration.