containerize workflow (pcottle/learnGitBranching)

The containerize workflow from pcottle/learnGitBranching, explained and optimized by Latchkey.

CI health: C - fair

Point runs-on at Latchkey and get run de-duplication, job timeouts, self-healing for flaky steps, and up to 58% lower cost, applied automatically.

Grade your own workflow free or run it on Latchkey →

Source: pcottle/learnGitBranching.github/workflows/containerize.ymlLicense MITView source

What it does

This is the containerize workflow from the pcottle/learnGitBranching 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

workflow (.yml)

name: containerize

on:
  push:
    branches: [ main ]
  workflow_dispatch:

jobs:
  build:
    runs-on: ubuntu-latest

    env:
      REPO_PREFIX: ghcr.io/${{ github.repository }}

    steps:
      - uses: actions/checkout@v4

      - name: login-ghcr
        run: echo ${{ secrets.GHCR_PAT }} | docker login ghcr.io -u ${{ github.actor }} --password-stdin

      - name: build-docker-image
        run: |
          REPO_PREFIX_LOWER=$(echo "$REPO_PREFIX" | tr '[:upper:]' '[:lower:]')
          docker build -t $REPO_PREFIX_LOWER:${{ github.sha }} -f Dockerfile .
          docker push $REPO_PREFIX_LOWER:${{ github.sha }}
          docker tag $REPO_PREFIX_LOWER:${{ github.sha }} $REPO_PREFIX_LOWER:latest
          docker push $REPO_PREFIX_LOWER:latest

The same workflow, on Latchkey

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

name: containerize
 
on:
  push:
    branches: [ main ]
  workflow_dispatch:
 
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  build:
    timeout-minutes: 30
    runs-on: latchkey-small
 
    env:
      REPO_PREFIX: ghcr.io/${{ github.repository }}
 
    steps:
      - uses: actions/checkout@v4
 
      - name: login-ghcr
        run: echo ${{ secrets.GHCR_PAT }} | docker login ghcr.io -u ${{ github.actor }} --password-stdin
 
      - name: build-docker-image
        run: |
          REPO_PREFIX_LOWER=$(echo "$REPO_PREFIX" | tr '[:upper:]' '[:lower:]')
          docker build -t $REPO_PREFIX_LOWER:${{ github.sha }} -f Dockerfile .
          docker push $REPO_PREFIX_LOWER:${{ github.sha }}
          docker tag $REPO_PREFIX_LOWER:${{ github.sha }} $REPO_PREFIX_LOWER:latest
          docker push $REPO_PREFIX_LOWER:latest

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.

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

actions/checkout