Development

Setting up a local copy of the Wagtail git repository is slightly more involved than running a release package of Wagtail, as it requires Node.js and NPM for building Javascript and CSS assets. (This is not required when running a release version, as the compiled assets are included in the release package.)

If you’re happy to develop on a virtual machine, the vagrant-wagtail-develop setup script is the fastest way to get up and running. This will provide you with a running instance of the Wagtail demo site, with the Wagtail and wagtaildemo codebases available as shared folders for editing on your host machine.

(Build scripts for other platforms would be very much welcomed - if you create one, please let us know via the Wagtail Developers group!)

If you’d prefer to set up all the components manually, read on. These instructions assume that you’re familiar with using pip and virtualenv to manage Python packages.

Setting up the Wagtail codebase

Install Node.js, version 4.x, 5.x or 6.x. Instructions for installing Node.js can be found on the Node.js download page. You can also use Node version manager (nvm) since Wagtail supplies a .nvmrc file in the root of the project with the minimum required Node version - see nvm’s installation instructions.

You will also need to install the libjpeg and zlib libraries, if you haven’t done so already - see Pillow’s platform-specific installation instructions.

Clone a copy of the Wagtail codebase:

$ git clone https://github.com/wagtail/wagtail.git
$ cd wagtail

With your preferred virtualenv activated, install the Wagtail package in development mode with the included testing and documentation dependencies:

$ pip install -e '.[testing,docs]' -U

Install Node through nvm (optional):

$ nvm install

Install the tool chain for building static assets:

$ npm install

Compile the assets:

$ npm run build

Any Wagtail sites you start up in this virtualenv will now run against this development instance of Wagtail. We recommend using the Wagtail demo site as a basis for developing Wagtail.

Testing

From the root of the Wagtail codebase, run the following command to run all the tests:

$ python runtests.py

Running only some of the tests

At the time of writing, Wagtail has well over 2500 tests, which takes a while to run. You can run tests for only one part of Wagtail by passing in the path as an argument to runtests.py:

$ python runtests.py wagtail.wagtailcore

You can also run tests for individual TestCases by passing in the path as an argument to runtests.py

$ python runtests.py wagtail.wagtailcore.tests.test_blocks.TestIntegerBlock

Testing against PostgreSQL

By default, Wagtail tests against SQLite. You can switch to using PostgreSQL by using the --postgres argument:

$ python runtests.py --postgres

If you need to use a different user, password or host. Use the PGUSER, PGPASSWORD and PGHOST environment variables.

Testing against a different database

If you need to test against a different database, set the DATABASE_ENGINE environment variable to the name of the Django database backend to test against:

$ DATABASE_ENGINE=django.db.backends.mysql python runtests.py

This will create a new database called test_wagtail in MySQL and run the tests against it.

Testing Elasticsearch

You can test Wagtail against Elasticsearch by passing the --elasticsearch argument to runtests.py:

$ python runtests.py --elasticsearch

Wagtail will attempt to connect to a local instance of Elasticsearch (http://localhost:9200) and use the index test_wagtail.

If your Elasticsearch instance is located somewhere else, you can set the ELASTICSEARCH_URL environment variable to point to its location:

$ ELASTICSEARCH_URL=http://my-elasticsearch-instance:9200 python runtests.py --elasticsearch

Browser and device support

Wagtail is meant to be used on a wide variety of devices and browsers. Supported browser / device versions include:

Browser Device/OS Version(s)
Mobile Safari iOS Phone Last 2
Mobile Safari iOS Tablet Last 2
Chrome Android Last 2
IE Desktop 11
Chrome Desktop Last 2
MS Edge Desktop Last 2
Firefox Desktop Latest
Firefox ESR Desktop Latest
Safari macOS Last 2

We aim for Wagtail to work in those environments. Our development standards ensure that the site is usable on other browsers and will work on future browsers. To test on IE, install virtual machines made available by Microsoft.

Unsupported browsers / devices include:

Browser Device/OS Version(s)
Stock browser Android All
IE Desktop 10 and below
Safari Windows All

Compiling static assets

All static assets such as JavaScript, CSS, images, and fonts for the Wagtail admin are compiled from their respective sources by gulp. The compiled assets are not committed to the repository, and are compiled before packaging each new release. Compiled assets should not be submitted as part of a pull request.

To compile the assets, run:

$ npm run build

This must be done after every change to the source files. To watch the source files for changes and then automatically recompile the assets, run:

$ npm start

Compiling the documentation

The Wagtail documentation is built by Sphinx. To install Sphinx and compile the documentation, run:

$ cd /path/to/wagtail
$ # Install the documentation dependencies
$ pip install -e .[docs]
$ # Compile the docs
$ cd docs/
$ make html

The compiled documentation will now be in docs/_build/html. Open this directory in a web browser to see it. Python comes with a module that makes it very easy to preview static files in a web browser. To start this simple server, run the following commands:

$ cd docs/_build/html/
$ # Python 2
$ python2 -mSimpleHTTPServer 8080
$ # Python 3
$ python3 -mhttp.server 8080

Now you can open <http://localhost:8080/> in your web browser to see the compiled documentation.

Sphinx caches the built documentation to speed up subsequent compilations. Unfortunately, this cache also hides any warnings thrown by unmodified documentation source files. To clear the built HTML and start fresh, so you can see all warnings thrown when building the documentation, run:

$ cd docs/
$ make clean
$ make html

Wagtail also provides a way for documentation to be compiled automatically on each change. To do this, you can run the following command to see the changes automatically at localhost:4000:

$ cd docs/
$ make livehtml