Fixed #8630: finished the custom comment app API that was left out of 1.0. This means it's now possible to override any of the models, forms, or views used by the comment app; see the new custom comment app docs for details and an example. Thanks to Thejaswi Puthraya for the original patch, and to carljm for docs and tests.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@9890 bcc190cf-cafb-0310-a4f2-bffc1f526a37

docs/ref/contrib/comments/custom.txt

@@ -0,0 +1,180 @@
+.. _ref-contrib-comments-custom:
+
+==================================
+Customizing the comments framework
+==================================
+
+.. currentmodule:: django.contrib.comments
+
+If the built-in comment framework doesn't quite fit your needs, you can extend
+the comment app's behavior to add custom data and logic. The comments framework
+lets you extend the built-in comment model, the built-in comment form, and the
+various comment views.
+
+The :setting:`COMMENTS_APP` setting is where this customization begins. Set
+:setting:`COMMENTS_APP` to the name of the app you'd like to use to provide
+custom behavior. You'll use the same syntax as you'd use for
+:setting:`INSTALLED_APPS`, and the app given must also be in the
+:setting:`INSTALLED_APPS` list.
+
+For example, if you wanted to use an app named ``my_comment_app``, your
+settings file would contain::
+
+    INSTALLED_APPS = [
+        ...
+        'my_comment_app',
+        ...
+    ]
+    
+    COMMENTS_APP = 'my_comment_app'
+
+The app named in :setting:`COMMENTS_APP` provides its custom behavior by
+defining some module-level functions in the app's ``__init__.py``. The
+:ref:`complete list of these functions <custom-comment-app-api>` can be found
+below, but first let's look at a quick example.
+
+An example custom comments app
+==============================
+
+One of the most common types of customization is modifying the set of fields
+provided on the built-in comment model. For example, some sites that allow
+comments want the commentator to provide a title for their comment; the built-in
+comment model has no field for that title.
+
+To make this kind of customization, we'll need to do three things:
+
+    #. Create a custom comment :class:`~django.db.models.Model` that adds on the
+       "title" field.
+    
+    #. Create a custom comment :class:`~django.forms.Form` that also adds this
+       "title" field.
+    
+    #. Inform Django of these objects by defining a few functions in a
+       custom :setting:`COMMENTS_APP`.
+       
+So, carrying on the example above, we're dealing with a typical app structure in
+the ``my_custom_app`` directory::
+
+    my_custom_app/
+        __init__.py
+        models.py
+        forms.py
+
+In the ``models.py`` we'll define a ``CommentWithTitle`` model::
+
+    from django.db import models
+    from django.contrib.comments.models import BaseCommentAbstractModel
+
+    class CommentWithTitle(BaseCommentAbstractModel):
+        title = models.CharField(max_length=300)
+    
+All custom comment models must subclass :class:`BaseCommentAbstractModel`.
+
+Next, we'll define a custom comment form in ``forms.py``. This is a little more
+tricky: we have to both create a form and override
+:meth:`CommentForm.get_comment_model` and
+:meth:`CommentForm.get_comment_create_data` to return deal with our custom title
+field::
+
+    from django import forms
+    from django.contrib.comments.forms import CommentForm
+    from my_comment_app.models import CommentWithTitle
+
+    class CommentFormWithTitle(CommentForm):
+        title = forms.CharField(max_length=300)
+        
+        def get_comment_model(self):
+            # Use our custom comment model instead of the built-in one.
+            return CommentWithTitle
+        
+        def get_comment_create_data(self):
+            # Use the data of the superclass, and add in the title field
+            data = super(CommentFormWithTitle, self).get_comment_create_data()
+            data['title'] = self.cleaned_data['title']
+            return data
+
+Finally, we'll define a couple of methods in ``my_custom_app/__init__.py`` to point Django at these classes we've created::
+
+    from my_comments_app.models import CommentWithTitle
+    from my_comments_app.forms import CommentFormWithTitle
+
+    def get_model():
+        return CommentWithTitle
+
+    def get_form():
+        return CommentFormWithTitle
+
+The above process should take care of most common situations. For more advanced usage, there are additional methods you can define. Those are explained in the next section.
+
+.. _custom-comment-app-api:
+
+Custom comment app API
+======================
+
+The :mod:`django.contrib.comments` app defines the following methods; any custom comment app must define at least one of them. All are optional, however.
+
+.. function:: get_model()
+
+    Return the :class:`~django.db.models.Model` class to use for comments. This
+    model should inherit from
+    :class:`django.contrib.comments.models.BaseCommentAbstractModel`, which
+    defines necessary core fields.
+
+    The default implementation returns
+    :class:`django.contrib.comments.models.Comment`.
+
+.. function:: get_form()
+
+    Return the :class:`~django.forms.Form` class you want to use for
+    creating, validating, and saving your comment model.  Your custom
+    comment form should accept an additional first argument,
+    ``target_object``, which is the object the comment will be
+    attached to.
+
+    The default implementation returns
+    :class:`django.contrib.comments.forms.CommentForm`.
+
+    .. note::
+
+        The default comment form also includes a number of unobtrusive
+        spam-prevention features (see
+        :ref:`notes-on-the-comment-form`).  If replacing it with your
+        own form, you may want to look at the source code for the
+        built-in form and consider incorporating similar features.
+
+.. function:: get_form_target()
+
+    Return the URL for POSTing comments. This will be the ``<form action>``
+    attribute when rendering your comment form.
+
+    The default implementation returns a reverse-resolved URL pointing
+    to the :func:`post_comment` view.
+
+    .. note::
+
+        If you provide a custom comment model and/or form, but you
+        want to use the default :func:`post_comment` view, you will
+        need to be aware that it requires the model and form to have
+        certain additional attributes and methods: see the
+        :func:`post_comment` view documentation for details.
+
+.. function:: get_flag_url()
+
+    Return the URL for the "flag this comment" view.
+
+    The default implementation returns a reverse-resolved URL pointing
+    to the :func:`django.contrib.comments.views.moderation.flag` view.
+
+.. function:: get_delete_url()
+
+    Return the URL for the "delete this comment" view.
+
+    The default implementation returns a reverse-resolved URL pointing
+    to the :func:`django.contrib.comments.views.moderation.delete` view.
+
+.. function:: get_approve_url()
+
+    Return the URL for the "approve this comment from moderation" view.
+
+    The default implementation returns a reverse-resolved URL pointing
+    to the :func:`django.contrib.comments.views.moderation.approve` view.

docs/ref/contrib/comments/index.txt

@@ -42,7 +42,7 @@ To get started using the ``comments`` app, follow these steps:
     #. Use the `comment template tags`_ below to embed comments in your
        templates.
     
-You might also want to examine the :ref:`ref-contrib-comments-settings`
+You might also want to examine :ref:`ref-contrib-comments-settings`.
     
 Comment template tags
 =====================
@@ -161,7 +161,7 @@ A complete form might look like::
     </form>
     
 Be sure to read the `notes on the comment form`_, below, for some special
-considerations you'll need to make if you're using this aproach.
+considerations you'll need to make if you're using this approach.
 
 .. templatetag:: comment_form_target
 
@@ -175,6 +175,8 @@ you'll always want to use it like above::
 
     <form action="{% comment_form_target %}" method="POST">
 
+.. _notes-on-the-comment-form:
+
 Notes on the comment form
 -------------------------
 
@@ -212,4 +214,4 @@ More information
    settings
    signals
    upgrade
-
+   custom

docs/ref/contrib/comments/settings.txt

@@ -29,6 +29,7 @@ this will be rejected. Defaults to 3000.
 COMMENTS_APP
 ------------
 
-The app (i.e. entry in ``INSTALLED_APPS``) responsible for all "business logic."
-You can change this to provide custom comment models and forms, though this is
-currently undocumented.
+An app which provides :ref:`customization of the comments framework
+<ref-contrib-comments-custom>`.  Use the same dotted-string notation
+as in :setting:`INSTALLED_APPS`.  Your custom :setting:`COMMENTS_APP`
+must also be listed in :setting:`INSTALLED_APPS`.