Post coverage comment workflow (Diaoul/subliminal)

The Post coverage comment workflow from Diaoul/subliminal, explained and optimized by Latchkey.

CI health: B - good

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Source: Diaoul/subliminal.github/workflows/coverage.yamlLicense MITView source

What it does

This is the Post coverage comment workflow from the Diaoul/subliminal 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: Post coverage comment

on:
  workflow_run:
    workflows: ["CI"]
    types:
      - completed

permissions: {}

concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true

env:
  FORCE_COLOR: "1"
  PIP_DISABLE_PIP_VERSION_CHECK: "1"
  PIP_NO_PYTHON_VERSION_WARNING: "1"

jobs:
  display-coverage:
    name: Display coverage comment
    runs-on: ubuntu-latest
    if: github.event.workflow_run.event == 'pull_request' && github.event.workflow_run.conclusion == 'success'
    permissions:
      pull-requests: write
      contents: write
      actions: read
    steps:
      # DO NOT run actions/checkout here, for security reasons
      # For details, refer to https://securitylab.github.com/research/github-actions-preventing-pwn-requests/
      - name: Post comment
        uses: py-cov-action/python-coverage-comment-action@v3
        with:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          GITHUB_PR_RUN_ID: ${{ github.event.workflow_run.id }}
          # Update those if you changed the default values:
          # COMMENT_ARTIFACT_NAME: python-coverage-comment-action
          # COMMENT_FILENAME: python-coverage-comment-action.txt

The same workflow, on Latchkey

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

name: Post coverage comment
 
on:
  workflow_run:
    workflows: ["CI"]
    types:
      - completed
 
permissions: {}
 
concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}
  cancel-in-progress: true
 
env:
  FORCE_COLOR: "1"
  PIP_DISABLE_PIP_VERSION_CHECK: "1"
  PIP_NO_PYTHON_VERSION_WARNING: "1"
 
jobs:
  display-coverage:
    timeout-minutes: 30
    name: Display coverage comment
    runs-on: latchkey-small
    if: github.event.workflow_run.event == 'pull_request' && github.event.workflow_run.conclusion == 'success'
    permissions:
      pull-requests: write
      contents: write
      actions: read
    steps:
      # DO NOT run actions/checkout here, for security reasons
      # For details, refer to https://securitylab.github.com/research/github-actions-preventing-pwn-requests/
      - name: Post comment
        uses: py-cov-action/python-coverage-comment-action@v3
        with:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
          GITHUB_PR_RUN_ID: ${{ github.event.workflow_run.id }}
          # Update those if you changed the default values:
          # COMMENT_ARTIFACT_NAME: python-coverage-comment-action
          # COMMENT_FILENAME: python-coverage-comment-action.txt

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.

1 third-party action is referenced by a movable tag. Pin it to the commit SHA (Latchkey resolves and applies this automatically) so a repointed tag cannot change what runs.

This workflow runs 1 job per trigger. On Latchkey the same minutes cost up to 58% less than GitHub-hosted, with zero queue time.