Mailfix Docker Build and Push workflow (cdhigh/KindleEar)

The Mailfix Docker Build and Push workflow from cdhigh/KindleEar, explained and optimized by Latchkey.

What it does

This is the Mailfix Docker Build and Push workflow from the cdhigh/KindleEar 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: Mailfix Docker Build and Push
permissions: read-all

on:
  workflow_dispatch:

jobs:
  build-and-push:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout code
        uses: actions/checkout@v2

      - name: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_PASSWORD }}

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v1

      - name: Build and push Docker image
        run: |
          cd docker/postfix
          docker buildx build --push --platform=linux/amd64,linux/arm64 -t kindleear/mailfix -f Dockerfile .

The same workflow, on Latchkey

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

name: Mailfix Docker Build and Push
permissions: read-all
 
on:
  workflow_dispatch:
 
jobs:
  build-and-push:
    timeout-minutes: 30
    runs-on: latchkey-small
    steps:
      - name: Checkout code
        uses: actions/checkout@v2
 
      - name: Login to Docker Hub
        uses: docker/login-action@v3
        with:
          username: ${{ secrets.DOCKER_USERNAME }}
          password: ${{ secrets.DOCKER_PASSWORD }}
 
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v1
 
      - name: Build and push Docker image
        run: |
          cd docker/postfix
          docker buildx build --push --platform=linux/amd64,linux/arm64 -t kindleear/mailfix -f Dockerfile .
 

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.
• 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