Development setup

This tutorial helps you to get started hacking with pretix on your own computer. You need this to be able to contribute to pretix, but it might also be helpful if you want to write your own plugins. If you want to install pretix on a server for actual usage, go to the Administrator documentation instead.

Obtain a copy of the source code

You can just clone our git repository:

git clone https://github.com/pretix/pretix.git
cd pretix/

External Dependencies

Your should install the following on your system:

  • Python 3.5 or newer

  • pip for Python 3 (Debian package: python3-pip)

  • python-dev for Python 3 (Debian package: python3-dev)

  • On Debian/Ubuntu: python-venv for Python 3 (Debian package: python3-venv)

  • libffi (Debian package: libffi-dev)

  • libssl (Debian package: libssl-dev)

  • libxml2 (Debian package libxml2-dev)

  • libxslt (Debian package libxslt1-dev)

  • libenchant-2-2 (Debian package libenchant-2-2)

  • msgfmt (Debian package gettext)

  • git

Your local python environment

Please execute python -V or python3 -V to make sure you have Python 3.4 (or newer) installed. Also make sure you have pip for Python 3 installed, you can execute pip3 -V to check. Then use Python’s internal tools to create a virtual environment and activate it for your current session:

python3 -m venv env
source env/bin/activate

You should now see a (env) prepended to your shell prompt. You have to do this in every shell you use to work with pretix (or configure your shell to do so automatically). If you are working on Ubuntu or Debian, we strongly recommend upgrading your pip and setuptools installation inside the virtual environment, otherwise some of the dependencies might fail:

pip3 install -U pip setuptools

Working with the code

If you do not have a recent installation of nodejs, install it now:

curl -sL https://deb.nodesource.com/setup_17.x | sudo -E bash -
sudo apt install nodejs

To make sure it is on your path variable, close and reopen your terminal. Now, install the Python-level dependencies of pretix:

pip3 install -e ".[dev]"

Next, you need to copy the SCSS files from the source folder to the STATIC_ROOT directory:

cd src/
python manage.py collectstatic --noinput

Then, create the local database:

python manage.py migrate

A first user with username admin@localhost and password admin will be automatically created.

You will also need to install a few JavaScript dependencies:

make npminstall

If you want to see pretix in a different language than English, you have to compile our language files:

make localecompile

Run the development server

To run the local development webserver, execute:

python manage.py runserver

and head to http://localhost:8000/

As we did not implement an overall front page yet, you need to go directly to http://localhost:8000/control/ for the admin view.

Note

If you want the development server to listen on a different interface or port (for example because you develop on pretixdroid), you can check Django’s documentation for more options.

When running the local development webserver, ensure Celery is not configured in pretix.cfg. i.e., you should remove anything such as:

[celery]
backend=redis://redis:6379/2
broker=redis://redis:6379/2

If you choose to use Celery for development, you must also start a Celery worker process:

celery -A pretix.celery_app worker -l info

However, beware that code changes will not auto-reload within Celery.

Code checks and unit tests

Before you check in your code into git, always run static checkers and linters. If any of these commands fail, your pull request will not be merged into pretix. If you have trouble figuring out why they fail, create your pull request nevertheless and ask us for help, we are happy to assist you.

Execute the following commands to check for code style errors:

flake8 .
isort -c .
python manage.py check

Execute the following command to run pretix’ test suite (might take a couple of minutes):

py.test

Note

If you have multiple CPU cores and want to speed up the test suite, you can install the python package pytest-xdist using pip3 install pytest-xdist and then run py.test -n NUM with NUM being the number of threads you want to use.

It is a good idea to put this command into your git hook .git/hooks/pre-commit, for example, to check for any errors in any staged files when committing:

#!/bin/bash

source ../env/bin/activate  # Adjust to however you activate your virtual environment
for file in $(git diff --cached --name-only | grep -E '\.py$' | grep -Ev "migrations|mt940\.py|pretix/settings\.py|make_testdata\.py|testutils/settings\.py|tests/settings\.py|pretix/base/models/__init__\.py|.*_pb2\.py")
do
  echo $file
  git show ":$file" | flake8 - --stdin-display-name="$file" || exit 1 # we only want to lint the staged changes, not any un-staged changes
  git show ":$file" | isort -c - | grep ERROR && exit 1 || true
done

This keeps you from accidentally creating commits violating the style guide.

Working with mails

If you want to test anything regarding emails in your development setup, we recommend starting Python’s debugging SMTP server in a separate shell and configuring pretix to use it. Every email will then be printed to the debugging SMTP server’s stdout.

Add this to your src/pretix.cfg:

[mail]
port = 1025

Then execute python -m smtpd -n -c DebuggingServer localhost:1025.

Working with periodic tasks

Periodic tasks (like sendmail rules) are run when an external scheduler (like cron) triggers the runperiodic command.

To run periodic tasks, execute python manage.py runperiodic.

Working with translations

If you want to translate new strings that are not yet known to the translation system, you can use the following command to scan the source code for strings to be translated and update the *.po files accordingly:

make localegen

However, most of the time you don’t need to care about this. Just create your pull request with functionality and English strings only, and we’ll push the new translation strings to our translation platform after the merge.

To actually see pretix in your language, you have to compile the *.po files to their optimized binary *.mo counterparts:

make localecompile

Working with the documentation

First, you should install the requirements necessary for building the documentation. Make sure you have your virtual python environment activated (see above). Then, install the packages by executing:

cd doc/
pip3 install -r requirements.txt

To build the documentation, run the following command from the doc/ directory:

make html

You will now find the generated documentation in the doc/_build/html/ subdirectory. If you work with the documentation a lot, you might find it useful to use sphinx-autobuild:

pip3 install sphinx-autobuild
sphinx-autobuild . _build/html -p 8081

Then, go to http://localhost:8081 for a version of the documentation that automatically re-builds whenever you change a source file.

Working with frontend assets

To update the frontend styles of shops with a custom styling, run the following commands inside your virtual environment.:

python -m pretix collectstatic --noinput
python -m pretix updateassets