==================================================== Howto extend the comment form with additional fields ==================================================== This document explains how to extend the plone.app.discussion comment form with additional fields in an add-on product. plone.app.discussion uses the `plone.z3cform.fieldsets `_ package which provides support for modifications via "extender" adapters. The idea is that a third party component can modify the fields in a form and the way that they are grouped and ordered. .. note:: This howto applies only to plone.app.discussion >= 2.0.4 and >= 1.1.2. Prior versions will not store the extended fields on the comment. .. seealso:: The source code of this howto can be found here: https://github.com/collective/example.commentextender/ Howto extend the comment form with an additional "website" field ================================================================ First, create a new plone package:: $ paster create -t plone example.commentextender Go to the main directory of the package (example.commentextender/example/commentextender) and create a new file *commentextender.py*. This file contains the ICommentExtenderFields interface definition with a "website" field, a persistent CommentExtenderFields class to store the value of the "website" field, a CommentExtenderFactory to create the CommentExtenderFields, and a CommentExtender class to extend the default comment form with the "website" field:: from persistent import Persistent from z3c.form.field import Fields from zope import interface from zope import schema from zope.annotation import factory from zope.component import adapter from zope.interface import Interface from zope.publisher.interfaces.browser import IDefaultBrowserLayer from plone.z3cform.fieldsets import extensible from plone.app.discussion.browser.comments import CommentForm from plone.app.discussion.comment import Comment # Interface to define the fields we want to add to the comment form. class ICommentExtenderFields(Interface): website = schema.TextLine(title=u"Website", required=False) # Persistent class that implements the ICommentExtenderFields interface @adapter(Comment) class CommentExtenderFields(Persistent): interface.implements(ICommentExtenderFields) website = u"" # CommentExtenderFields factory CommentExtenderFactory = factory(CommentExtenderFields) # Extending the comment form with the fields defined in the # ICommentExtenderFields interface. @adapter(Interface, IDefaultBrowserLayer, CommentForm) class CommentExtender(extensible.FormExtender): fields = Fields(ICommentExtenderFields) def __init__(self, context, request, form): self.context = context self.request = request self.form = form def update(self): # Add the fields defined in ICommentExtenderFields to the form. self.add(ICommentExtenderFields, prefix="") # Move the website field to the top of the comment form. self.move('website', before='text', prefix="") .. seealso:: * See the plone.z3cform pypi page for more documentation about how to add, hide, and reorder fields: http://pypi.python.org/pypi/plone.z3cform#fieldsets-and-form-extenders Now register the CommentExtenderFactory and CommentExtender Classes that has been created by adding the following lines to your configure.zcml:: Create a new Plone instance, globally allow commenting, allow commenting on a content object and you will see a comment form with an additional "website" field. Since we do not only want to store the "website" value on the comments, but also to show these values for existing comments, we have to override the comments viewlet. The easiest way to do this is to use z3c.jbot. First, add `z3c.jbot `_. to the setup.py of the example.commentextender package:: install_requires=[ ... 'z3c.jbot', ], Next, create a new directory called "overrides" inside the example.commentextender package and register it together with z3c.jbot in your configure.zcml:: ... Copy plone.app.discussion/plone/app/discussion/browser/comments.pt to the overrides directory we just created and rename comments.pt to plone.app.discussion.browser.comments.pt. You can now add code to show the website attribute to the documentByLine::
...
Restart your Plone instance and you will see the "website" field in the documentByLine next to the comments.