build workflow (Buuntu/fastapi-react)

The build workflow from Buuntu/fastapi-react, explained and optimized by Latchkey.

What it does

This is the build workflow from the Buuntu/fastapi-react 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

on:
  push:
    branches: [master]
  pull_request:
    branches: [master]

jobs:
  build:
    runs-on: ubuntu-latest

    steps:
      - uses: actions/checkout@v2
      - name: Set up Python 3.8
        uses: actions/setup-python@v2
        with:
          python-version: 3.8
      - name: Install dependencies
        run: |
          sudo python -m pip install --upgrade pip
          sudo pip install cookiecutter
      - name: Prettify code
        uses: creyD/prettier_action@v2.2
        with:
          prettier_options: --write **/*.{ts,tsx,md}
      - name: Black Code Formatter
        uses: lgeiger/black-action@master
        with:
          args: '{{cookiecutter.project_slug}}/backend --check --line-length 79'
      - name: Run tests
        run: |
          sudo ./scripts/test.sh

The same workflow, on Latchkey

Estimated ~20% faster on cache hits, plus fewer wasted runs and a safer supply chain. Added and changed lines are highlighted.

name: build
 
on:
  push:
    branches: [master]
  pull_request:
    branches: [master]
 
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  build:
    timeout-minutes: 30
    runs-on: latchkey-small
 
    steps:
      - uses: actions/checkout@v2
      - name: Set up Python 3.8
        uses: actions/setup-python@v2
        with:
          cache: 'pip'
          python-version: 3.8
      - name: Install dependencies
        run: |
          sudo python -m pip install --upgrade pip
          sudo pip install cookiecutter
      - name: Prettify code
        uses: creyD/prettier_action@v2.2
        with:
          prettier_options: --write **/*.{ts,tsx,md}
      - name: Black Code Formatter
        uses: lgeiger/black-action@master
        with:
          args: '{{cookiecutter.project_slug}}/backend --check --line-length 79'
      - name: Run tests
        run: |
          sudo ./scripts/test.sh
 

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.
• Cache dependency installs on the setup step so they are served from cache.
• 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:

• Dependency installs

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