我正在通过示例实现Django一书中的博客应用程序。到第2章它工作正常但是当我尝试实现rss feed时，它在我运行浏览器时出现以下错误：
Request Method: GET
Request URL: http://127.0.0.1:8000/blog/feed/
Django Version: 1.9.6
Python Version: 3.5.1
Installed Applications:
['django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'blog',
'taggit',
'django.contrib.sites',
'django.contrib.sitemaps']
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware']
Traceback:
File "d:\virEnv\lib\site-packages\django\core\handlers\base.py" in get_response
149. response = self.process_exception_by_middleware(e, request)
File "d:\virEnv\lib\site-packages\django\core\handlers\base.py" in get_response
147. response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "d:\virEnv\lib\site-packages\django\contrib\syndication\views.py" in __call__
41. feedgen = self.get_feed(obj, request)
File "d:\virEnv\lib\site-packages\django\contrib\syndication\views.py" in get_feed
169. for item in self.__get_dynamic_attr('items', obj):
Exception Type: TypeError at /blog/feed/
Exception Value: 'NoneType' object is not iterable
这是我的feeds.py:
from django.contrib.syndication.views import Feed
from django.template.defaultfilters import truncatewords
from .models import Post
class LatestPostsFeed(Feed):
title = 'My blog'
link = '/blog/'
description = 'New posts of my blog.'
def items(self):
return Post.published.all()[:5]
def item_title(self, item):
return item.title
def item_description(self, item):
return truncatewords(item.body, 30)
这是我的网址：
from .feeds import LatestPostsFeed
url(r'^feed/$', LatestPostsFeed(), name='post_feed')
为什么不在浏览器中使用此代码？以前我安装了markdown == 2.6.6。它会导致任何阻碍吗？
编辑：我的views.py文件：
from django.db.models import Count
from django.core.paginator import (Paginator, EmptyPage, PageNotAnInteger)
from django.views.generic import ListView
from .forms import EmailPostForm, CommentForm
from django.shortcuts import render, get_object_or_404
from django.core.mail import send_mail
from .models import Post, Comment
from taggit.models import Tag
# Create your views here.
def post_list(request, tag_slug=None):
object_list = Post.published.all()
tag = None
if tag_slug:
tag = get_object_or_404(Tag, slug=tag_slug)
object_list = object_list.filter(tags__in=[tag])
paginator = Paginator(object_list, 3) # 3 posts in each page
page = request.GET.get('page')
try:
posts = paginator.page(page)
except PageNotAnInteger:
# If page is not an integer deliver the first page
posts = paginator.page(1)
except EmptyPage:
# If page is out of range deliver last page of results
posts = paginator.page(paginator.num_pages)
return render(request, 'blog/post/list.html', {'page': page,
'posts': posts,
'tag': tag})
def post_detail(request, year, month, day, post):
post = get_object_or_404(Post, slug=post,
status='published',
publish__year=year,
publish__month=month,
publish__day=day)
# List of active comments for this post
comments = post.comments.filter(active=True)
if request.method == 'POST':
# A comment was posted
comment_form = CommentForm(data=request.POST)
if comment_form.is_valid():
# Create Comment object but don't save to database yet
new_comment = comment_form.save(commit=False)
# Assign the current post to the comment
new_comment.post = post
# Save the comment to the database
new_comment.save()
else:
comment_form = CommentForm()
# List of similar posts
post_tags_ids = post.tags.values_list('id', flat=True)
similar_posts = Post.published.filter(tags__in=post_tags_ids)\
.exclude(id=post.id)
similar_posts = similar_posts.annotate(same_tags=Count('tags'))\
.order_by('-same_tags','-publish')[:4]
return render(request,
'blog/post/detail.html',
{'post': post,
'comments': comments,
'comment_form': comment_form,
'similar_posts': similar_posts,})
def post_share(request, post_id):
# Retrieve post by id
post = get_object_or_404(Post,id=post_id,status='published')
sent = False
if request.method == 'POST':
# Form was submitted
form = EmailPostForm(request.POST)
if form.is_valid():
# Form fields passed validation
cd = form.cleaned_data
# ... send email
post_url = request.build_absolute_uri( post.get_absolute_url())
subject = '{} ({}) recommends you reading "{}"'.format(cd['name'], cd['email'], post.title)
message = 'Read "{}" at {}\n\n{}\'s comments: {}'.format(post.title, post_url, cd['name'], cd['comments'])
send_mail(subject, message, 'admin@example.com',[cd['to']])
sent = True
else:
form = EmailPostForm()
return render(request,
'blog/post/share.html', {'post': post,
'form': form,
'sent': sent,
})