tri.form 1.7.0

tri.form is a form library

.. image:: https://travis-ci.org/TriOptima/tri.form.svg?branch=master
:target: https://travis-ci.org/TriOptima/tri.form

.. image:: http://codecov.io/github/TriOptima/tri.form/coverage.svg?branch=master
:target: http://codecov.io/github/TriOptima/tri.form?branch=master


tri.form
==========

tri.form is alternative forms library for Django. It is inspired by, and comes from a frustration with, the standard Django forms.

Major features compared to Django forms:

- Supports :code:`__` syntax for going across table boundaries, similar to how Django does with QuerySets.
- Send in a callable that is late evaluated to determine if a field should be displayed (:code:`show`). This is very handy for showing a slightly different form to administrators for example.
- Easy configuration without writing entire classes that are only used in one place anyway.


Example
-------

You can either create a subclass of :code:`Form`...

.. code:: python

class UserForm(Form):
name = Field.text()
username = Field.text(is_valid=lambda form, field, parsed_data: parsed_data.startswith('demo_'))
is_admin = Field.boolean(
show=lambda form, field: form.request.user.is_staff, # show only for staff
label_template='tweak_label_tag.html')

def edit_user_view(request, username):
form = UserForm(request=request)

user = User.objects.get(username=username)
if form.is_valid() and request.method == 'POST':
form.apply(user)
user.save()
return HttpRedirect('..')

return render(
template_name='edit_user.html',
context_instance=RequestContext(request, {'form': form}))

.. code:: html

<!-- edit_user.html -->
<form action="" method="post">{% csrf_token %}
<div>
<table>
{{ form }}
</table>
</div>
<input type="submit" value="Save" />
</form>

or just instantiate a :code:`Form` with a :code:`Field` list and use it directly:

.. code:: python

def edit_user_view(request, username):
form = Form(fields=[
Field.text(
name='name',
is_valid=lambda form, field, parsed_data: parsed_data.startswith('demo_')),
Field.text(name='username'),
Field.boolean(
name='is_admin',
show=lambda form, field: form.request.user.is_staff, # show only for staff
label_template='tweak_label_tag.html',)])

# rest of view function...


You can also generate forms from Django models automatically (but still change the behavior!). The above example
is equivalent to:

.. code:: python

def edit_user_view(request, username):
form = Form.from_model(
request.POST,
User,
# the field 'name' is generated automatically and we are fine with the defaults
username__is_valid=lambda form, field, parsed_data: parsed_data.startswith('demo_'),
is_admin__label_template='tweak_label_tag.html',
is_admin__show=lambda form, field: form.request.user.is_staff) # show only for staff

# rest of view function...

or even better: use :code:`tri.form.views.create_or_edit_object`:

.. code:: python

def edit_user_view(request, username):
return create_or_edit_object(
request,
model=User,
is_create=False,
instance=User.objects.get(username=username),

form__username__is_valid=lambda form, field, parsed_data: parsed_data.startswith('demo_'),
form__is_admin__label_template='tweak_label_tag.html',
form__is_admin__show=lambda form, field: form.request.user.is_staff) # show only for staff
# no html template! tri.form has a nice default for you :P

tri.form pre-packages sets of defaults for common field types as 'shortcuts'. Some examples include :code:`Field.boolean`,
:code:`Field.integer` and :code:`Field.choice`. The full list of shortcuts can be found in the `API documentation for Field <api.html#tri.form.Field>`_.


Running tests
-------------

You need tox installed then just `make test`.


License
-------

BSD


Documentation
-------------

http://triform.readthedocs.org.


Changelog
=========

1.7.0 (2016-01-13)
~~~~~~~~~~~~~~~~~~

* Made evaluation of choices lazy even when there is a None alternative.