flatpak-builder-lint

flatpak-builder-lint is a linter for Flatpak artifacts like Flatpak manifests, Flatpak Builder build artifacts and repos. It is primarily developed for Flathub, but can be useful for general use as well.

Checks

There are four checks available right now - the appstream check, the manifest check, the builddir check and the repo check. The manifest and the repo checks are run on Flathub infrastructure.

• The appstream check expects path to a Metainfo file as input.
• The manifest check expects path to a Flatpak manifest as input.
• The builddir check expects path to a build directory generated by Flatpak Builder as input.
• The repo check expects path to an OSTree repository exported by Flatpak Builder as input.

The last two are created when building the application with the proper arguments to Flatpak Builder.

Some checks may require network connectivity.

Errors can be overridden through exceptions. Exceptions must be submitted to Flathub.

Installation

The only supported ways to install and use are Flatpak and Docker.

Flatpak

flatpak-builder-lint is part of the org.flatpak.Builder flatpak package available on Flathub. Set up FlatHub first, then install org.flatpak.Builder:

flatpak install flathub -y org.flatpak.Builder
flatpak run --command=flatpak-builder-lint org.flatpak.Builder --help

# Run the manifest check
flatpak run --command=flatpak-builder-lint org.flatpak.Builder manifest com.foo.bar.json

# Run the repo check
flatpak run --command=flatpak-builder-lint org.flatpak.Builder repo repo

The Flatpak package tracks the git commit currently used on the Flathub infrastructure.

Docker

The latest build of flatpak-builder-linter can be used with Docker.

docker run --rm -it ghcr.io/flathub/flatpak-builder-lint:latest --help

# Run the manifest check
docker run -v $(pwd):/mnt --rm -it ghcr.io/flathub/flatpak-builder-lint:latest manifest /mnt/com.foo.bar.json

# Run the repo check
docker run -v $(pwd):/mnt --rm -it ghcr.io/flathub/flatpak-builder-lint:latest repo /mnt/repo

You may need to pass :Z if your distro is using SELinux like so -v $(pwd):/mnt:Z.

Local environment

Installing flatpak-builder-lint locally with Poetry or pip is not recommended unless for development purposes. It depends on patches that are found in the org.flatpak.Builder flatpak package and on external tools.

Contributing

The following system dependencies must be installed:

• libgirepository1.0-dev, gir1.2-ostree-1.0
• flatpak-builder for validating flatpak-builder manifests
• appstreamcli from org.flatpak.Builder for validating MetaInfo files

#!/bin/sh

exec flatpak run --branch=stable --command=appstreamcli org.flatpak.Builder ${@}

• desktop-file-validate to validate desktop files
• git to check if a directory is a git repository

Debiab/Ubuntu:

# apt install git appstream flatpak-builder libgirepository1.0-dev gir1.2-ostree-1.0 libcairo2-dev desktop-file-utils

ArchLinux:

# pacman -S --needed git appstream flatpak-builder desktop-file-utils ostree glib2

Fedora:

# dnf install git appstream flatpak-builder desktop-file-utils ostree-libs glib2-devel cairo-devel

Then the project can be installed with:

git clone https://github.com/flathub/flatpak-builder-lint.git && cd flatpak-builder-lint
poetry install
poetry run flatpak-builder-lint --help

After making changes to any dependencies run poetry lock --no-update to regenerate the lockfile and poetry install --sync to synchronise the virtual environment.

When adding new checks, please do not increase the minimum requirements set in {builddir, repo}/min_success_metadata.

The virtual enviroment can be listed with poetry env list and removed with poetry env remove flatpak-builder-lint-xxxxxxxx-py3.xx.

The following Python dependencies are installed by Poetry and needed to run jsonschema^4.19.1, requests^2.32.2, requests-cache^1.2.1, lxml^5.2.2, sentry-sdk^2.8.0, PyGObject^3.48.2. Additionally poetry-core>=1.0.0 is necessary to build. poetry-dynamic-versioning is used to generate a version from the git commit, since no tags or releases are done.

Ruff is used to lint and format code. MyPy is used to check Python types. To run them:

# Formatting
poetry run ruff format .

# Linting
poetry run ruff check .

# Auto fix some lint errrors
poetry run ruff check --fix .

# Check python types
poetry run mypy .

A pre-commit hook is provided to automate the formatting and linting:

poetry run pre-commit install
poetry run pre-commit run --all-files

# Uninstall hooks
poetry run pre-commit uninstall

Tests

Pytest is used to run tests:

poetry run pytest -v tests

An additional Flat manager test can be run when modifying code relying on the flatmanager check. The test is meant to be run on CI and not locally. If it is being run locally, it must be run from the root of the git repository using

./tests/flatmanager.sh

# Avoid repeated rebuilds
NO_CLEAN_UP=1 ./tests/flatmanager.sh

To write tests for manifest checks, recreate a minimal Flatpak builder manifest with the cases to check against and put it in tests/manifests. Then add the test using it (or modify the existing tests) in tests/test_manifest.py.

Similarly to add a test for builddir check, recreate the metadata file and the build directory contents that Flatpak builder creates. Then put it in tests/builddir and add the test in tests/test_builddir.py. Please avoid adding large files or binary files that aren't readable (compressed appstream catalogue data is fine).

Usage

usage: flatpak-builder-lint [-h] [--version] [--exceptions] [--appid APPID] [--cwd] [--ref REF] {appstream,manifest,builddir,repo} path

A linter for Flatpak builds and flatpak-builder manifests

positional arguments:
  {appstream,manifest,builddir,repo}
                        Type of artifact to lint

                        appstream expects a MetaInfo file
                        manifest expects a flatpak-builder manifest
                        builddir expects a flatpak-builder build directory
                        repo expects an OSTree repo exported by flatpak-builder
  path                  Path to the artifact

options:
  -h, --help            Show this help message and exit
  --version             Show the version number and exit
  --exceptions
                        Skip warnings or errors added to exceptions.
                        Exceptions must be submitted to Flathub
  --appid APPID         Override the app ID
  --cwd                 Override the path parameter with current working directory
  --ref REF             Override the primary ref detection

If you consider the detected issues incorrect, please report it here: https://github.com/flathub/flatpak-builder-lint

Documentation

A list of errors and warnings and their explanations are available in the Flatpak builder lint page.