==================
Writing Extensions
==================
.. versionadded:: 0.2

This tutorial will explain to you how to write extensions to Formular. An
extension can provide field, form and widget types. Once your extension is
installed these can be imported seamlessly.

You write an extension just like any other application. In your setup.py you
have to specifiy an entry point::

    from setuptools import setup

    setup(
        name="Your Plugin",
        version="0.1",
        description="Spam fields for Formular",
        entry_points="""
        [formular.extensions]
        whatever = your_module:data
        """
    )

As you can see `formular.extensions` is the entry point but what is `data`?
It's simply a dictionary which looks like this::

    data = {
        "fields": {"YourField": YourField}
    }

Possible keys are ``"fields"``, ``"widgets"`` and ``"forms"``. ``"YourField"``
will be the name under which ``YourField`` will be reachable.