Linters workflow (aio-libs/multidict)
The Linters workflow from aio-libs/multidict, explained and optimized by Latchkey.
CI health: B - good
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What it does
This is the Linters workflow from the aio-libs/multidict repository, a real project running GitHub Actions. It is shown here with attribution under its Apache-2.0 license.
Below, Latchkey shows a faster, safer version produced by its optimization engine.
The workflow
---
name: Linters
on:
workflow_call:
env:
COLOR: >- # Supposedly, pytest or coveragepy use this
yes
FORCE_COLOR: 1 # Request colored output from CLI tools supporting it
MYPY_FORCE_COLOR: 1 # MyPy's color enforcement
PIP_DISABLE_PIP_VERSION_CHECK: 1
PIP_NO_PYTHON_VERSION_WARNING: 1
PIP_NO_WARN_SCRIPT_LOCATION: 1
PRE_COMMIT_COLOR: always
PY_COLORS: 1 # Recognized by the `py` package, dependency of `pytest`
PYTHONIOENCODING: utf-8
PYTHONUTF8: 1
PYTHON_LATEST: 3.12
jobs:
lint:
name: Linter
runs-on: ubuntu-latest
timeout-minutes: 5
steps:
- name: Checkout
uses: actions/checkout@v7
- name: Setup Python ${{ env.PYTHON_LATEST }}
uses: actions/setup-python@v6
with:
python-version: ${{ env.PYTHON_LATEST }}
- name: Cache PyPI
uses: actions/cache@v6
with:
key: pip-lint-${{ hashFiles('requirements/*.txt') }}
path: ~/.cache/pip
restore-keys: |
pip-lint-
- name: Cache pre-commit.com virtualenvs
uses: actions/cache@v6
with:
path: ~/.cache/pre-commit
key: >-
${{
runner.os
}}-pre-commit-${{
hashFiles('.pre-commit-config.yaml')
}}
- name: Install dependencies
uses: py-actions/py-dependency-install@v4
with:
path: requirements/lint.txt
- name: Run linters
run: |
make lint
- name: Send coverage data to Coveralls
uses: coverallsapp/github-action@v2
with:
debug: ${{ runner.debug == 1 && true || false }}
fail-on-error: ${{ runner.debug == 1 && false || true }}
files: >-
.tox/.tmp/.mypy/python-3.13/cobertura.xml
.tox/.tmp/.mypy/python-3.11/cobertura.xml
flag-name: MyPy
format: cobertura
measure: ${{ runner.debug == 1 && true || false }}
- name: Install spell checker
run: |
pip install -r requirements/doc.txt
- name: Run docs spelling
run: |
make doc-spelling
- name: Prepare twine checker
run: |
pip install -U build twine
python -m build
env:
MULTIDICT_NO_EXTENSIONS: 1
- name: Run twine checker
run: |
twine check --strict dist/*
...
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: Linters on: workflow_call: env: COLOR: >- # Supposedly, pytest or coveragepy use this yes FORCE_COLOR: 1 # Request colored output from CLI tools supporting it MYPY_FORCE_COLOR: 1 # MyPy's color enforcement PIP_DISABLE_PIP_VERSION_CHECK: 1 PIP_NO_PYTHON_VERSION_WARNING: 1 PIP_NO_WARN_SCRIPT_LOCATION: 1 PRE_COMMIT_COLOR: always PY_COLORS: 1 # Recognized by the `py` package, dependency of `pytest` PYTHONIOENCODING: utf-8 PYTHONUTF8: 1 PYTHON_LATEST: 3.12 jobs: lint: name: Linter runs-on: latchkey-small timeout-minutes: 5 steps: - name: Checkout uses: actions/checkout@v7 - name: Setup Python ${{ env.PYTHON_LATEST }} uses: actions/setup-python@v6 with: cache: 'pip' python-version: ${{ env.PYTHON_LATEST }} - name: Cache PyPI uses: actions/cache@v6 with: key: pip-lint-${{ hashFiles('requirements/*.txt') }} path: ~/.cache/pip restore-keys: | pip-lint- - name: Cache pre-commit.com virtualenvs uses: actions/cache@v6 with: path: ~/.cache/pre-commit key: >- ${{ runner.os }}-pre-commit-${{ hashFiles('.pre-commit-config.yaml') }} - name: Install dependencies uses: py-actions/py-dependency-install@v4 with: path: requirements/lint.txt - name: Run linters run: | make lint - name: Send coverage data to Coveralls uses: coverallsapp/github-action@v2 with: debug: ${{ runner.debug == 1 && true || false }} fail-on-error: ${{ runner.debug == 1 && false || true }} files: >- .tox/.tmp/.mypy/python-3.13/cobertura.xml .tox/.tmp/.mypy/python-3.11/cobertura.xml flag-name: MyPy format: cobertura measure: ${{ runner.debug == 1 && true || false }} - name: Install spell checker run: | pip install -r requirements/doc.txt - name: Run docs spelling run: | make doc-spelling - name: Prepare twine checker run: | pip install -U build twine python -m build env: MULTIDICT_NO_EXTENSIONS: 1 - name: Run twine checker run: | twine check --strict dist/* ...
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 useslatchkey-small; pick the runner size that fits the job. - Cache dependency installs on the setup step so they are served from cache.
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.