Publish Repo image workflow (engineer-man/piston)

The Publish Repo image workflow from engineer-man/piston, explained and optimized by Latchkey.

What it does

This is the Publish Repo image workflow from the engineer-man/piston repository, a real project running GitHub Actions. It is shown here with attribution under its MIT license.

Below, Latchkey shows a faster, safer version produced by its optimization engine.

The workflow

name: Publish Repo image
on:
    push:
        branches:
            - master
            - v3
        paths:
            - repo/**

jobs:
    push_to_registry:
        runs-on: ubuntu-latest
        name: Build and Push Docker image to Github Packages
        steps:
            - name: Check out repo
              uses: actions/checkout@v3
            - name: Login to GitHub registry
              uses: docker/login-action@v2
              with:
                  username: ${{ github.actor }}
                  password: ${{ secrets.GITHUB_TOKEN }}
                  registry: docker.pkg.github.com

            - name: Build and push repo
              uses: docker/build-push-action@v4
              with:
                  context: repo
                  pull: true
                  push: true
                  tags: |
                      docker.pkg.github.com/engineer-man/piston/repo-builder

The same workflow, on Latchkey

Removes redundant runs and caps runaway jobs. Added and changed lines are highlighted.

name: Publish Repo image
on:
    push:
        branches:
            - master
            - v3
        paths:
            - repo/**
 
concurrency:
    group: ${{ github.workflow }}-${{ github.ref }}
    cancel-in-progress: true
 
jobs:
    push_to_registry:
        timeout-minutes: 30
        runs-on: latchkey-small
        name: Build and Push Docker image to Github Packages
        steps:
            - name: Check out repo
              uses: actions/checkout@v3
            - name: Login to GitHub registry
              uses: docker/login-action@v2
              with:
                  username: ${{ github.actor }}
                  password: ${{ secrets.GITHUB_TOKEN }}
                  registry: docker.pkg.github.com
 
            - name: Build and push repo
              uses: docker/build-push-action@v4
              with:
                  context: repo
                  pull: true
                  push: true
                  tags: |
                      docker.pkg.github.com/engineer-man/piston/repo-builder
 

What changed

• Run on Latchkey managed runners with one line (runs-on), which apply the fixes below automatically and self-heal transient failures. This example uses latchkey-small; pick the runner size that fits the job.
• Cancel superseded runs when a branch or PR gets a newer push.
• Add a job timeout so a hung step cannot burn hours of runner time.

2 third-party actions are referenced by a movable tag. Pin them to the commit SHA (Latchkey resolves and applies this automatically) so a repointed tag cannot change what runs.

What Latchkey heals here

This workflow has steps that commonly fail on transient issues (network, registries, flaky browsers). On Latchkey managed runners they are detected, retried, and self-healed instead of failing your build:

• Container pulls and builds

This workflow runs 1 job per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.

Actions used in this workflow