The static code checks in Airflow are used to verify that the code meets certain quality standards. All the static code checks can be run through pre-commit hooks.
The pre-commit hooks perform all the necessary installation when you run them for the first time. See the table below to identify which pre-commit checks require the Breeze Docker images.
You can also run some static code check via Breeze environment using available bash scripts.
Pre-commit hooks help speed up your local development cycle and place less burden on the CI infrastructure. Consider installing the pre-commit hooks as a necessary prerequisite.
The pre-commit hooks by default only check the files you are currently working on and make them fast. Yet, these checks use exactly the same environment as the CI tests use. So, you can be sure your modifications will also work for CI if they pass pre-commit hooks.
We have integrated the fantastic pre-commit framework in our development workflow. To install and use it, you need at least Python 3.8 locally.
It is the best to use pre-commit hooks when you have your local virtualenv for
Airflow activated since then pre-commit hooks and other dependencies are
automatically installed. You can also install the pre-commit hooks manually
using pip install
.
pip install pre-commit
After installation, pre-commit hooks are run automatically when you commit the code and they will
only run on the files that you change during your commit, so they are usually pretty fast and do
not slow down your iteration speed on your changes. There are also ways to disable the pre-commits
temporarily when you commit your code with --no-verify
switch or skip certain checks that you find
to much disturbing your local workflow. See Available pre-commit checks
and Using pre-commit
Note
Additional prerequisites might be needed
The pre-commit hooks use several external linters that need to be installed before pre-commit is run.
Each of the checks installs its own environment, so you do not need to install those, but there are some
checks that require locally installed binaries. On Linux, you typically install
them with sudo apt install
, on macOS - with brew install
.
The current list of prerequisites is limited to xmllint
:
- on Linux, install via
sudo apt install libxml2-utils
- on macOS, install via
brew install libxml2
Some pre-commit hooks also require the Docker Engine to be configured as the static checks are executed in the Docker environment (See table in the Available pre-commit checks . You should build the images locally before installing pre-commit checks as described in BREEZE.rst.
Sometimes your image is outdated and needs to be rebuilt because some dependencies have been changed. In such cases, the Docker-based pre-commit will inform you that you should rebuild the image.
In case you do not have your local images built, the pre-commit hooks fail and provide instructions on what needs to be done.
To turn on pre-commit checks for commit
operations in git, enter:
pre-commit install
To install the checks also for pre-push
operations, enter:
pre-commit install -t pre-push
For details on advanced usage of the install method, use:
pre-commit install --help
This table lists pre-commit hooks used by Airflow. The Image
column indicates which hooks
require Breeze Docker image to be built locally.
Note
Manual pre-commits
Most of the checks we run are configured to run automatically when you commit the code. However,
there are some checks that are not run automatically and you need to run them manually. Those
checks are marked with manual
in the Description
column in the table below. You can run
them manually by running pre-commit run --hook-stage manual <hook-id>
.
Note
Disabling particular checks
In case you have a problem with running particular pre-commit
check you can still continue using the
benefits of having pre-commit
installed, with some of the checks disabled. In order to disable
checks you might need to set SKIP
environment variable to coma-separated list of checks to skip. For example,
when you want to skip some checks (ruff/mypy for example), you should be able to do it by setting
export SKIP=ruff,mypy-core,
. You can also add this to your .bashrc
or .zshrc
if you
do not want to set it manually every time you enter the terminal.
In case you do not have breeze image configured locally, you can also disable all checks that require breeze
the image by setting SKIP_BREEZE_PRE_COMMITS
to "true". This will mark the tests as "green" automatically
when run locally (note that those checks will anyway run in CI).
Note
Mypy checks
When we run mypy checks locally when committing a change, one of the mypy-*
checks is run, mypy-core
,
mypy-dev
, mypy-providers
, mypy-docs
, depending on the files you are changing. The mypy checks
are run by passing those changed files to mypy. This is way faster than running checks for all files (even
if mypy cache is used - especially when you change a file in airflow core that is imported and used by many
files). However, in some cases, it produces different results than when running checks for the whole set
of files, because mypy
does not even know that some types are defined in other files and it might not
be able to follow imports properly if they are dynamic. Therefore in CI we run mypy
check for whole
directories (airflow
- excluding providers, airflow/providers
, dev
and docs
) to make sure
that we catch all mypy
errors - so you can experience different results when running mypy locally and
in CI. If you want to run mypy checks for all files locally, you can do it by running the following
command (example for airflow
files):
MYPY_PACKAGES="airflow" pre-commit run --hook-stage manual mypy --all-files
Note
Mypy volume cache
MyPy uses a separate docker-volume (called mypy-cache-volume
) that keeps the cache of last MyPy
execution in order to speed MyPy checks up (sometimes by order of magnitude). While in most cases MyPy
will handle refreshing the cache when and if needed, there are some cases when it won't (cache invalidation
is the hard problem in computer science). This might happen for example when we upgrade MyPY. In such
cases you might need to manually remove the cache volume by running breeze down --cleanup-mypy-cache
.
ID | Description | Image |
---|---|---|
bandit | bandit | |
blacken-docs | Run black on Python code blocks in documentation files | |
check-aiobotocore-optional | Check if aiobotocore is an optional dependency only | |
check-airflow-k8s-not-used | Check airflow.kubernetes imports are not used | |
check-airflow-provider-compatibility | Check compatibility of Providers with Airflow | |
check-airflow-providers-bug-report-template | Check airflow-bug-report provider list is sorted/unique | |
check-apache-license-rat | Check if licenses are OK for Apache | |
check-base-operator-partial-arguments | Check BaseOperator and partial() arguments | |
check-base-operator-usage |
|
|
check-boring-cyborg-configuration | Checks for Boring Cyborg configuration consistency | |
check-breeze-top-dependencies-limited | Breeze should have small number of top-level dependencies | |
check-builtin-literals | Require literal syntax when initializing builtin types | |
check-changelog-has-no-duplicates | Check changelogs for duplicate entries | |
check-cncf-k8s-only-for-executors | Check cncf.kubernetes imports used for executors only | |
check-core-deprecation-classes | Verify usage of Airflow deprecation classes in core | |
check-daysago-import-from-utils | Make sure days_ago is imported from airflow.utils.dates | |
check-decorated-operator-implements-custom-name | Check @task decorator implements custom_operator_name | |
check-deferrable-default-value | Check default value of deferrable attribute | |
check-docstring-param-types | Check that docstrings do not specify param types | |
check-example-dags-urls | Check that example dags url include provider versions | |
check-executables-have-shebangs | Check that executables have shebang | |
check-extra-packages-references | Checks setup extra packages | |
check-extras-order | Check order of extras in Dockerfile | |
check-fab-migrations | Check no migration is done on FAB related table | |
check-for-inclusive-language | Check for language that we do not accept as community | |
check-google-re2-as-dependency | Check google-re2 is declared as dependency when needed | |
check-hooks-apply | Check if all hooks apply to the repository | |
check-incorrect-use-of-LoggingMixin | Make sure LoggingMixin is not used alone | |
check-init-decorator-arguments | Check model __init__ and decorator arguments are in sync | |
check-integrations-list-consistent | Sync integrations list with docs | |
check-lazy-logging | Check that all logging methods are lazy | |
check-links-to-example-dags-do-not-use-hardcoded-versions | Verify example dags do not use hard-coded version numbers | |
check-merge-conflict | Check that merge conflicts are not being committed | |
check-newsfragments-are-valid | Check newsfragments are valid | |
check-no-airflow-deprecation-in-providers | Do not use DeprecationWarning in providers | |
check-no-providers-in-core-examples | No providers imports in core example DAGs | |
check-no-relative-imports | No relative imports | |
check-only-new-session-with-provide-session | Check NEW_SESSION is only used with @provide_session | |
check-persist-credentials-disabled-in-github-workflows | Check that workflow files have persist-credentials disabled | |
check-pre-commit-information-consistent | Validate hook IDs & names and sync with docs | |
check-provide-create-sessions-imports | Check provide_session and create_session imports | |
check-provider-docs-valid | Validate provider doc files | |
check-provider-yaml-valid | Validate provider.yaml files | |
check-providers-init-file-missing | Provider init file is missing | |
check-providers-subpackages-init-file-exist | Provider subpackage init files are there | |
check-pydevd-left-in-code | Check for pydevd debug statements accidentally left | |
check-revision-heads-map | Check that the REVISION_HEADS_MAP is up-to-date | |
check-safe-filter-usage-in-html | Don't use safe in templates | |
check-setup-order | Check order of dependencies in setup.cfg and setup.py | |
check-sql-dependency-common-data-structure | Check dependency of SQL Providers with common data structure | |
check-start-date-not-used-in-defaults | start_date not to be defined in default_args in example_dags | |
check-system-tests-present | Check if system tests have required segments of code | |
check-system-tests-tocs | Check that system tests is properly added | |
check-tests-unittest-testcase | Check that unit tests do not inherit from unittest.TestCase | |
check-urlparse-usage-in-code | Don't use urlparse in code | |
check-usage-of-re2-over-re | Use re2 module instead of re | |
check-xml | Check XML files with xmllint | |
codespell | Run codespell to check for common misspellings in files | |
compile-www-assets | Compile www assets (manual) | |
compile-www-assets-dev | Compile www assets in dev mode (manual) | |
create-missing-init-py-files-tests | Create missing init.py files in tests | |
debug-statements | Detect accidentally committed debug statements | |
detect-private-key | Detect if private key is added to the repository | |
doctoc | Add TOC for Markdown and RST files | |
end-of-file-fixer | Make sure that there is an empty line at the end | |
fix-encoding-pragma | Remove encoding header from Python files | |
flynt | Run flynt string format converter for Python | |
generate-airflow-diagrams | Generate airflow diagrams | |
generate-pypi-readme | Generate PyPI README | |
identity | Print input to the static check hooks for troubleshooting | |
insert-license |
|
|
lint-chart-schema | Lint chart/values.schema.json file | |
lint-css | stylelint | |
lint-dockerfile | Lint Dockerfile | |
lint-helm-chart | Lint Helm Chart | |
lint-json-schema |
|
|
lint-markdown | Run markdownlint | |
lint-openapi |
|
|
mixed-line-ending | Detect if mixed line ending is used (r vs. rn) | |
mypy | Run mypy for specified packages (manual) | |
mypy-core | Run mypy for core | |
mypy-dev | Run mypy for dev | |
mypy-docs | Run mypy for /docs/ folder | |
mypy-providers | Run mypy for providers | |
pretty-format-json | Format JSON files | |
python-no-log-warn | Check if there are no deprecate log warn | |
replace-bad-characters | Replace bad characters | |
rst-backticks | Check if RST files use double backticks for code | |
ruff | Run 'ruff' for extremely fast Python linting | |
ruff-format | Run 'ruff format' for extremely fast Python formatting | |
shellcheck | Check Shell scripts syntax correctness | |
trailing-whitespace | Remove trailing whitespace at end of line | |
ts-compile-format-lint-www | TS types generation / ESLint / Prettier against UI files | |
update-black-version | Update black versions everywhere | |
update-breeze-cmd-output | Update output of breeze commands in BREEZE.rst | |
update-breeze-readme-config-hash | Update Breeze README.md with config files hash | |
update-common-sql-api-stubs | Check and update common.sql API stubs | |
update-er-diagram | Update ER diagram | |
update-extras | Update extras in documentation | |
update-in-the-wild-to-be-sorted | Sort INTHEWILD.md alphabetically | |
update-inlined-dockerfile-scripts | Inline Dockerfile and Dockerfile.ci scripts | |
update-installed-providers-to-be-sorted | Sort alphabetically and uniquify installed_providers.txt | |
update-local-yml-file | Update mounts in the local yml file | |
update-migration-references | Update migration ref doc | |
update-providers-dependencies | Update cross-dependencies for providers packages | |
update-spelling-wordlist-to-be-sorted | Sort alphabetically and uniquify spelling_wordlist.txt | |
update-supported-versions | Updates supported versions in documentation | |
update-vendored-in-k8s-json-schema | Vendor k8s definitions into values.schema.json | |
update-version | Update version to the latest version in the documentation | |
validate-pyproject | Validate pyproject.toml | |
yamllint | Check YAML files with yamllint |
After installation, pre-commit hooks are run automatically when you commit the code. But you can run pre-commit hooks manually as needed.
- Run all checks on your staged files by using:
pre-commit run
- Run only mypy check on your staged files (in
airflow/
excluding providers) by using:
pre-commit run mypy-core
- Run only mypy checks on all files by using:
pre-commit run mypy-core --all-files
- Run all checks on all files by using:
pre-commit run --all-files
- Run all checks only on files modified in the last locally available commit in your checked out branch:
pre-commit run --source=HEAD^ --origin=HEAD
- Show files modified automatically by pre-commit when pre-commits automatically fix errors
pre-commit run --show-diff-on-failure
- Skip one or more of the checks by specifying a comma-separated list of checks to skip in the SKIP variable:
SKIP=mypy-core,ruff pre-commit run --all-files
You can always skip running the tests by providing --no-verify
flag to the
git commit
command.
To check other usage types of the pre-commit framework, see Pre-commit website.
The static code checks can be launched using the Breeze environment.
You run the static code checks via breeze static-check
or commands.
You can see the list of available static checks either via --help
flag or by using the autocomplete
option.
Run the mypy
check for the currently staged changes (in airflow/
excluding providers):
breeze static-checks --type mypy-core
Run the mypy
check for all files:
breeze static-checks --type mypy-core --all-files
Run the ruff
check for the tests/core.py
file with verbose output:
breeze static-checks --type ruff --file tests/core.py --verbose
Run the ruff
check for the tests.core
package with verbose output:
breeze static-checks --type ruff --file tests/core/* --verbose
Run the ruff-format
check for the files airflow/example_dags/example_bash_operator.py
and
airflow/example_dags/example_python_operator.py
:
breeze static-checks --type ruff-format --file airflow/example_dags/example_bash_operator.py \
airflow/example_dags/example_python_operator.py
Run all checks for the currently staged files:
breeze static-checks
Run all checks for all files:
breeze static-checks --all-files
Run all checks for last commit:
breeze static-checks --last-commit
Run all checks for all changes in my branch since branched from main:
breeze static-checks --type mypy-core --only-my-changes
More examples can be found in Breeze documentation
Those commits that use Breeze docker image might sometimes fail, depending on your operating system and
docker setup, so sometimes it might be required to run debugging with the commands. This is done via
two environment variables VERBOSE
and DRY_RUN
. Setting them to "true" will respectively show the
commands to run before running them or skip running the commands.
Note that you need to run pre-commit with --verbose command to get the output regardless of the status of the static check (normally it will only show output on failure).
Printing the commands while executing:
VERBOSE="true" pre-commit run --verbose ruff
Just performing dry run:
DRY_RUN="true" pre-commit run --verbose ruff