Build Docker image workflow (Spenhouet/confluence-markdown-exporter)

The Build Docker image workflow from Spenhouet/confluence-markdown-exporter, explained and optimized by Latchkey.

What it does

This is the Build Docker image workflow from the Spenhouet/confluence-markdown-exporter 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: Build Docker image

on:
  pull_request:
    branches: [main]
    paths:
      - Dockerfile
      - .dockerignore
      - .github/workflows/docker-build.yml
      - pyproject.toml
      - uv.lock
      - confluence_markdown_exporter/**
  # Also build on push to main so the GHA cache is primed on the default
  # branch. Tag-triggered publish runs fall back to the default branch's
  # cache, which would otherwise stay cold until the first release.
  push:
    branches: [main]
    paths:
      - Dockerfile
      - .dockerignore
      - .github/workflows/docker-build.yml
      - pyproject.toml
      - uv.lock
      - confluence_markdown_exporter/**

permissions:
  contents: read

jobs:
  build:
    name: Build image (PR verification)
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v7

      - name: Set up QEMU
        uses: docker/setup-qemu-action@v4

      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4

      - name: Build (no push)
        uses: docker/build-push-action@v7
        with:
          context: .
          file: ./Dockerfile
          platforms: linux/amd64,linux/arm64
          push: false
          cache-from: type=gha
          cache-to: type=gha,mode=max,ignore-error=true

The same workflow, on Latchkey

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

name: Build Docker image
 
on:
  pull_request:
    branches: [main]
    paths:
      - Dockerfile
      - .dockerignore
      - .github/workflows/docker-build.yml
      - pyproject.toml
      - uv.lock
      - confluence_markdown_exporter/**
  # Also build on push to main so the GHA cache is primed on the default
  # branch. Tag-triggered publish runs fall back to the default branch's
  # cache, which would otherwise stay cold until the first release.
  push:
    branches: [main]
    paths:
      - Dockerfile
      - .dockerignore
      - .github/workflows/docker-build.yml
      - pyproject.toml
      - uv.lock
      - confluence_markdown_exporter/**
 
permissions:
  contents: read
 
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  build:
    timeout-minutes: 30
    name: Build image (PR verification)
    runs-on: latchkey-small
    steps:
      - name: Checkout
        uses: actions/checkout@v7
 
      - name: Set up QEMU
        uses: docker/setup-qemu-action@v4
 
      - name: Set up Docker Buildx
        uses: docker/setup-buildx-action@v4
 
      - name: Build (no push)
        uses: docker/build-push-action@v7
        with:
          context: .
          file: ./Dockerfile
          platforms: linux/amd64,linux/arm64
          push: false
          cache-from: type=gha
          cache-to: type=gha,mode=max,ignore-error=true
 

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.

3 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