yyafl 0.2.1 is now available

Yann — Fri, 23 Jan 2009 05:59:19 +0000

yyafl, a Python web form library operating on domain objects, now has version 0.2.1 available for download. This release includes numerous fixes for decorators, including the ability to attach multiple decorators to a form field or the wildcard ‘*’ field.

An example is given below, in the context of a CherryPy handler. This example is available in the download as

examples/layout02.py

import cherrypy
import yyafl
import yyafl.layout
from yyafl import fields
from yyafl.widgets import HiddenInput
 
# This example covers the user of custom decorators for required form fields
 
class Form1(yyafl.Form):
    name = fields.CharField(label = "User name", required = True)
    email = fields.CharField(label = "Your e-mail address", required = True)
    optional = fields.CharField(label = "Optional field", required = False)
    hidden = fields.CharField(widget = HiddenInput, default = "123")
    _layout = yyafl.layout.TableLayout()
 
class RequiredDecorator(yyafl.layout.NullDecorator):
    """ Draw a * next to all required fields """
    def extra_markup_widget(self, field, rendered_text):
        if field.required:
            return rendered_text + " * "
        return rendered_text
 
class FormTest(object):
 
    @cherrypy.expose
    def index(self, **kwargs):
        f = Form1(data = kwargs)
        # Add a global decorator
        f.layout().add_decorator('*', RequiredDecorator())
        content = ""
        content += ""
 
        if f.is_valid() == False:
            content += "Errors: "
            for error in f.errors:
                content += error + " : " + f.errors[error] + "
"
        elif f.is_bound() and f.is_valid():
            content += "Thanks for the data!"
 
 
        content += "
\"GET\" action=\"/\">"
 
        # Render using the layout specified in _layout above.
        content += f.render()
        # Or invoke the layout explicitly
        # l = yyafl.layout.TableLayout()
        # l.render(f)
 
        content += "
 "
        return content
 
 
if __name__ == '__main__':
    cherrypy.quickstart(root = FormTest())

yyafl now has layout support, with decorators

Yann — Tue, 30 Sep 2008 07:35:17 +0000

Just finished adding in a flexible layout system to yyafl, my reimplementation of Django newforms for other Python web frameworks or WSGI adapters. Now its simple to add default layouts or render a different layout on demand.

For example, to add a simple TableLayout() to a form:

class Form1(yyafl.Form):
    name = fields.CharField(label = "User name", required = True)
    email = fields.CharField(label = "Your e-mail address", required = True)
    hidden = fields.CharField(widget = HiddenInput, default = "123")
    _layout = yyafl.layout.TableLayout()

and to render the form to HTML:

# Render using the layout specified in _layout above.
content += f.render()
# Or invoke the layout explicitly
l = yyafl.layout.TableLayout()
content += l.render(f)

yyafl Layout()s also understand decorators:

decorators = { '*' : MarkRequiredDecorator(),
    'name_field' : HighlightDecorator() }
layout = yyafl.layout.TableLayout(decorators = decorators)
layout.render(f)

Decorators can change attributes and wrap fields in markup blocks. In the above example, the ‘*’ signifies the decorator should apply to all fields, and the HighlightDecorator should only apply to the field called ‘name_field’.

There are still some not yet implemented ideas:

It doesn’t generated the
blocks yet, you need to roll your own.
Field reordering and grouping isn’t supported by the default layout engines yet, though you could write your own.
No AJAX form support (though its coming!)
Automatic CSRF prevention forms.
Error message printing in the form.

You can find these latest changes in the Git repository linked from the main yyafl web page.

Yann's Blog » yyafl

yyafl 0.2.1 is now available

yyafl now has layout support, with decorators