github-act-runner

A reverse engineered github actions compatible self-hosted runner using nektos/act to execute your workflow steps. Unlike the official actions/runner, this works on more systems like freebsd.

Usage

Dependencies

Docker Daemon via DOCKER_HOST

(*1) Reachable docker daemon use DOCKER_HOST to specify a remote host.

NodeJS via PATH

(*2) For best compatibility with existing nodejs actions, please add nodejs in version 12 to your PATH, newer nodejs versions might lead to workflow failures.

Usage for github releases

Follow the instruction of https://github.com/ChristopherHX/github-act-runner/releases/latest.

Usage for debian repository

Add debian repository

/etc/apt/sources.list.d/github-act-runner.list file:

deb https://gagis.hopto.org/repo/chrishx/deb all main

Import repository public key

curl -sS https://gagis.hopto.org/repo/chrishx/pubkey.gpg | sudo tee -a /etc/apt/trusted.gpg.d/chrishx-github-act-runner.asc

Install the runner

sudo apt update
sudo apt install github-act-runner

Add new runner

github-act-runner new --url <url> --name <runner-name> --labels <labels> --token <runner-registration-token>

where

• <url> - github repository (e.g. https://github.com/user/repo), organization (e.g. https://github.com/organization) or enterprise URL
• <runner-name> - choose a name for your runner
• <labels> - comma-separated list of labels, e.g. label1,label2. Optional.
• <runner-registration-token>

The new runner will be registered and started as background service.

See help:

github-act-runner --help

For more info about managing runners.

Usage from source

You need at least go 1.21 to use this runner from source.

Getting Source

git clone https://github.com/ChristopherHX/github-act-runner.git --recursive

Update Source

git pull
git submodule update

Configure

go run . configure --url <github-repo-or-org-or-enterprise> --name <name of this runner> -l label1,label2 --token <runner registration token>

<github-repo-or-org-or-enterprise>

E.g. https://github.com/ChristopherHX/github-act-runner for this repo

<name of this runner>

E.g. Test

<runner registration token>

E.g. AWWWWWWWWWWWWWAWWWWWWAWWWWWWW

Labels

Replace label1,label2 with a custom list of runner labels.

Run

go run . run

Breaking changes in 0.6.0

• runner.os changed from darwin to macOS
• runner.arch changed from x86_64 to x64
• runner.arch changed from 386 to x86
• runner.arch changed from aarch64 to arm64
• shell parameter might behave differently
• based on nektos/act@65ef31f102ceb75623973921099454637bab55b0
• the docker client has been removed from openbsd builds
• windows runners now prefers pwsh and powershell as default shell, while running directly on windows
• all other systems now fallback to sh if bash is not found
• now requires go 1.18 to compile
• protocol.JobLogger moved to "protocol/logger" package

Breaking changes in 0.7.0

• based on nektos/act@f3350e2acbd2812cf3dd9bd8324387be05fce755
• removed openbsd/mips binaries, because this prevents updates to go and dependencies
• go 1.21 now required

Known Limitations

• This runner ignores pre and post steps of javascript actions Is now working in 0.6.0
• actions/cache is incompatible and won't be able to save your cache
  • Using https://github.com/actions/toolkit/tree/main/packages/cache directly should allow you to save your cache Is now working in 0.6.0, including hashfiles
• You won't be able to run steps after a failure without using continue-on-error: true Implemented since v0.2.0 via nektos/act contribution ( https://github.com/nektos/act/commit/1891c72ab158508e36009d16b24913fa5836422b )
• The expression interpreter of this runner doesn't always behave like you would expect and you might see errors or other expressions which shouldn't work are working here ( based on javascript, not on actions/runner ) v0.2.0 uses rhysd/actionlint instead with much better compatibility https://github.com/nektos/act/pull/908
• add-mask command not implemented Is now working in 0.6.0
• Running steps after cancellation Is now working in 0.6.0
• steps.timeout-minutes not implemented Is now working in 0.6.0
• Service Container are not implemented Is now working in 0.7.0
• Step Summaries are not implemented (only file command is provided)
• Annotations are not implemented
• Problem Matcher are not implemented
• Expressions in with and env (also applies to workflow and job env blocks) keys / directly assign to a mapping expression are not implemented
• Secret masking may leak more secrets than the one of actions/runner
• Job Outputs are sent regardless if they would leak secret data to non secret storage
• You need to provide the node program yourself in all containers / host configurations
• You need to manually update the runner
• Most issues of https://github.com/nektos/act/issues applies to this runner as well

How does it work?

This runner implements the same protocol as the actions/runner in a different way, as such it can be used as a self-hosted runner exactly like the official one. To get this working, I initially built an actions service replacement ChristopherHX/runner.server for the official actions/runner. My own actions service allowed me to implement the base protocol for this runner and debug how the protocol is serializeing and parsing json messages, while still being incompatible with github. After testing against github, the first thing happend was loosing the ability to run any github action workflows on my test repository. My invalid attempts to register a custom runner caused unrecoverable Internal Server Errors on githubs side, I decided to delete this test repository. After some work everything worked and finally it is safe to register this runner against github. To execute steps this runner translates the github actions job request to be compatible with a modified version of nektos/act ( ChristopherHX/act ), which adds a local task runner without the need for docker and increased platform support, also the log output of act gets redirected to github for live logs and storing log files.

Does this runner work without github?

Yes, you can use this runner together with ChristopherHX/runner.server locally on your PC without depending on compatibility with github. Also CI tests for this runner are using ChristopherHX/runner.server, this avoids requiring a PAT for github to run tests and enshures that you are always able to run it locally without github.