Contributions are welcome and are greatly appreciated! Every little bit helps, and credit will always be given.
Report bugs through Apache Jira
Please report relevant information and preferably code that exhibits the problem.
Look through the Jira issues for bugs. Anything is open to whoever wants to implement it.
Look through the Apache Jira for features. Any unassigned "Improvement" issue is open to whoever wants to implement it.
We've created the operators, hooks, macros and executors we needed, but we made sure that this part of Airflow is extensible. New operators, hooks, macros and executors are very welcomed!
Airflow could always use better documentation,
whether as part of the official Airflow docs,
in docstrings, docs/*.rst or even on the web as blog posts or
articles.
The best way to send feedback is to open an issue on Apache Jira
If you are proposing a feature:
- Explain in detail how it would work.
- Keep the scope as narrow as possible, to make it easier to implement.
- Remember that this is a volunteer-driven project, and that contributions are welcome :)
The latest API documentation is usually available
here. To generate a local version,
you need to have set up an Airflow development environment (see below). Also
install the doc extra.
pip install -e .[doc]
Generate and serve the documentation by running:
cd docs
./build.sh
./start_doc_server.sh
Only a subset of the API reference documentation builds. Install additional extras to build the full API reference.
Go to your Airflow directory and start a new docker container. You can choose between Python 2 or 3, whatever you prefer.
# Start docker in your Airflow directory
docker run -t -i -v `pwd`:/airflow/ -w /airflow/ -e SLUGIFY_USES_TEXT_UNIDECODE=yes python:2 bash
# Install Airflow with all the required dependencies,
# including the devel which will provide the development tools
pip install -e .[devel,druid,hdfs,hive]
# Init the database
airflow initdb
nosetests -v tests/hooks/test_druid_hook.py
test_get_first_record (tests.hooks.test_druid_hook.TestDruidDbApiHook) ... ok
test_get_records (tests.hooks.test_druid_hook.TestDruidDbApiHook) ... ok
test_get_uri (tests.hooks.test_druid_hook.TestDruidDbApiHook) ... ok
test_get_conn_url (tests.hooks.test_druid_hook.TestDruidHook) ... ok
test_submit_gone_wrong (tests.hooks.test_druid_hook.TestDruidHook) ... ok
test_submit_ok (tests.hooks.test_druid_hook.TestDruidHook) ... ok
test_submit_timeout (tests.hooks.test_druid_hook.TestDruidHook) ... ok
test_submit_unknown_response (tests.hooks.test_druid_hook.TestDruidHook) ... ok
----------------------------------------------------------------------
Ran 8 tests in 3.036s
OK
The Airflow code is mounted inside of the Docker container, so if you change something using your favorite IDE, you can directly test is in the container.
Please install python(2.7.x or 3.4.x), mysql, and libxml by using system-level package managers like yum, apt-get for Linux, or homebrew for Mac OS at first. It is usually best to work in a virtualenv and tox. Install development requirements:
cd $AIRFLOW_HOME
virtualenv env
source env/bin/activate
pip install -e .[devel]
tox
Feel free to customize based on the extras available in setup.py
Before you submit a pull request from your forked repo, check that it meets these guidelines:
- The pull request should include tests, either as doctests, unit tests, or both. The airflow repo uses Travis CI to run the tests and codecov to track coverage. You can set up both for free on your fork (see the "Testing on Travis CI" section below). It will help you making sure you do not break the build with your PR and that you help increase coverage.
- Please rebase your fork, squash commits, and resolve all conflicts.
- Every pull request should have an associated JIRA. The JIRA link should also be contained in the PR description.
- Preface your commit's subject & PR's title with [AIRFLOW-XXX] where XXX is the JIRA number. We compose release notes (i.e. for Airflow releases) from all commit titles in a release. By placing the JIRA number in the commit title and hence in the release notes, Airflow users can look into JIRA and Github PRs for more details about a particular change.
- Add an Apache License header to all new files
- If the pull request adds functionality, the docs should be updated as part of the same PR. Doc string are often sufficient. Make sure to follow the Sphinx compatible standards.
- The pull request should work for Python 2.7 and 3.4. If you need help writing code that works in both Python 2 and 3, see the documentation at the Python-Future project (the future package is an Airflow requirement and should be used where possible).
- As Airflow grows as a project, we try to enforce a more consistent style and try to follow the Python community guidelines. We track this using landscape.io, which you can setup on your fork as well to check before you submit your PR. We currently enforce most PEP8 and a few other linting rules. It is usually a good idea to lint locally as well using flake8 using
flake8 airflow tests.git diff upstream/master -u -- "*.py" | flake8 --diffwill return any changed files in your branch that require linting. - Please read this excellent article on commit messages and adhere to them. It makes the lives of those who come after you a lot easier.
We currently rely heavily on Travis CI for running the full Airflow test suite as running all of the tests locally requires significant setup. You can setup Travis CI in your fork of Airflow by following the Travis CI Getting Started guide.
There are two different options available for running Travis CI which are setup as separate components on GitHub:
- Travis CI GitHub App (new version)
- Travis CI GitHub Services (legacy version)
-
Once installed, you can configure the Travis CI GitHub App at https://github.com/settings/installations/169040.
-
For the Travis CI GitHub App, you can set repository access to either "all repositories" for convenience, or "only select repositories" and choose
<username>/incubator-airflowin the dropdown. -
You can access Travis CI for your fork at
https://travis-ci.com/<username>/incubator-airflow.
The Travis CI GitHub Services versions uses an Authorized OAuth App. Note
that apache/incubator-airflow is currently still using the legacy version.
-
Once installed, you can configure the Travis CI Authorized OAuth App at https://github.com/settings/connections/applications/88c5b97de2dbfc50f3ac.
-
If you are a GitHub admin, click the "Grant" button next to your organization; otherwise, click the "Request" button.
-
For the Travis CI Authorized OAuth App, you may have to grant access to the forked
<organization>/incubator-airflowrepo even though it is public. -
You can access Travis CI for your fork at
https://travis-ci.org/<organization>/incubator-airflow.
The travis-ci.org site for open source projects is now legacy and new projects should instead be created on travis-ci.com for both private repos and open source.
Note that there is a second Authorized OAuth App available called "Travis CI for Open Source" used for the legacy travis-ci.org service. It should not be used for new projects.
More information:
- Open Source on travis-ci.com
- Legacy GitHub Services to GitHub Apps Migration Guide
- Migrating Multiple Repositories to GitHub Apps Guide
Tests can then be run with (see also the Running unit tests section below):
./run_unit_tests.sh
Individual test files can be run with:
nosetests [path to file]
We highly recommend setting up Travis CI on your repo to automate this. It is free for open source projects. If for some reason you cannot, you can use the steps below to run tests.
Here are loose guidelines on how to get your environment to run the unit tests. We do understand that no one out there can run the full test suite since Airflow is meant to connect to virtually any external system and that you most likely have only a subset of these in your environment. You should run the CoreTests and tests related to things you touched in your PR.
To set up a unit test environment, first take a look at run_unit_tests.sh and
understand that your AIRFLOW_CONFIG points to an alternate config file
while running the tests. You shouldn't have to alter this config file but
you may if need be.
From that point, you can actually export these same environment variables in
your shell, start an Airflow webserver airflow webserver -d and go and
configure your connection. Default connections that are used in the tests
should already have been created, you just need to point them to the systems
where you want your tests to run.
Once your unit test environment is setup, you should be able to simply run
./run_unit_tests.sh at will.
For example, in order to just execute the "core" unit tests, run the following:
./run_unit_tests.sh tests.core:CoreTest -s --logging-level=DEBUG
or a single test method:
./run_unit_tests.sh tests.core:CoreTest.test_check_operators -s --logging-level=DEBUG
For more information on how to run a subset of the tests, take a look at the nosetests docs.
See also the list of test classes and methods in tests/core.py.
When developing features the need may arise to persist information to the the metadata database. Airflow has Alembic built-in to handle all schema changes. Alembic must be installed on your development machine before continuing.
# starting at the root of the project
$ pwd
~/airflow
# change to the airflow directory
$ cd airflow
$ alembic revision -m "add new field to db"
Generating
~/airflow/airflow/migrations/versions/12341123_add_new_field_to_db.py
airflow/www_rbac/ contains all npm-managed, front end assets.
Flask-Appbuilder itself comes bundled with jQuery and bootstrap.
While these may be phased out over time, these packages are currently not
managed with npm.
Make sure you are using recent versions of node and npm. No problems have been found with node>=8.11.3 and npm>=6.1.3
First, npm must be available in your environment. If it is not you can run the following commands (taken from this source)
brew install node --without-npm
echo prefix=~/.npm-packages >> ~/.npmrc
curl -L https://www.npmjs.com/install.sh | sh
The final step is to add ~/.npm-packages/bin to your PATH so commands you install globally are usable.
Add something like this to your .bashrc file, then source ~/.bashrc to reflect the change.
export PATH="$HOME/.npm-packages/bin:$PATH"
To install third party libraries defined in package.json, run the
following within the airflow/www_rbac/ directory which will install them in a
new node_modules/ folder within www_rbac/.
# from the root of the repository, move to where our JS package.json lives
cd airflow/www_rbac/
# run npm install to fetch all the dependencies
npm installTo parse and generate bundled files for airflow, run either of the
following commands. The dev flag will keep the npm script running and
re-run it upon any changes within the assets directory.
# Compiles the production / optimized js & css
npm run prod
# Start a web server that manages and updates your assets as you modify them
npm run dev
Should you add or upgrade a npm package, which involves changing package.json, you'll need to re-run npm install
and push the newly generated package-lock.json file so we get the reproducible build.
We try to enforce a more consistent style and try to follow the JS community guidelines. Once you add or modify any javascript code in the project, please make sure it follows the guidelines defined in Airbnb JavaScript Style Guide. Apache Airflow uses ESLint as a tool for identifying and reporting on patterns in JavaScript, which can be used by running any of the following commands.
# Check JS code in .js and .html files, and report any errors/warnings
npm run lint
# Check JS code in .js and .html files, report any errors/warnings and fix them if possible
npm run lint:fix