build workflow (Mayukhdeb/torch-dreams)

The build workflow from Mayukhdeb/torch-dreams, explained and optimized by Latchkey.

What it does

This is the build workflow from the Mayukhdeb/torch-dreams 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

# This is a basic workflow to help you get started with Actions

name: build

# Controls when the action will run. 
on:
  # Triggers the workflow on push or pull request events but only for the master branch
  push:
    branches: [ master, dev ]
  pull_request:
    branches: [ master ]

# A workflow run is made up of one or more jobs that can run sequentially or in parallel
jobs:
  # This workflow contains a single job called "build"
  build:
    # The type of runner that the job will run on
    runs-on: ubuntu-20.04

    # Steps represent a sequence of tasks that will be executed as part of the job
    steps:
      - uses: actions/checkout@v2
      - name: Install Python 3
        uses: actions/setup-python@v1
        with:
          python-version: 3.8
      - name: Install dependencies
        run: |
          python -m pip install --upgrade pip
          pip install -r requirements.txt
          pip install pytest
      - name: Run tests
        run: pytest torch_dreams/tests/*

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.

# This is a basic workflow to help you get started with Actions
 
name: build
 
# Controls when the action will run. 
on:
  # Triggers the workflow on push or pull request events but only for the master branch
  push:
    branches: [ master, dev ]
  pull_request:
    branches: [ master ]
 
# A workflow run is made up of one or more jobs that can run sequentially or in parallel
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
jobs:
  # This workflow contains a single job called "build"
  build:
    timeout-minutes: 30
    # The type of runner that the job will run on
    runs-on: latchkey-small
 
    # Steps represent a sequence of tasks that will be executed as part of the job
    steps:
      - uses: actions/checkout@v2
      - name: Install Python 3
        uses: actions/setup-python@v1
        with:
          cache: 'pip'
          python-version: 3.8
      - name: Install dependencies
        run: |
          python -m pip install --upgrade pip
          pip install -r requirements.txt
          pip install pytest
      - name: Run tests
        run: pytest torch_dreams/tests/*
 

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.

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