为什么 Django 模板没有显示任何输出？

Question

所以，在这里我正在使用 django 编写一个简单的新闻应用程序，但模板似乎不起作用，它没有显示从views.py传递的任何输出。 我已经检查了settings.py ， INSTALLED_APPS设置它正在工作

views.py

from django.shortcuts import render,HttpResponse

import bs4
from bs4 import BeautifulSoup as soup
from urllib.request import urlopen


def get_news():
    news_link = "https://news.google.com/news/rss"
    page = urlopen(news_link)
    xml_page = page.read()
    page.close()

    soup_page = soup(xml_page,"xml")
    news_list = soup_page.findAll("item")
    return news_list



def index(request):
    news_list = get_news()
    return render(request,'main/index.html',{'news_list' : news_list})

和模板

    {% for news in news_list %}
    <h3> {{ news.title.text }} </h3>
    <h3> {{ news.pubDate.text }} </h3>
    {% endfor %}

如果我从 render() 字典传递任何其他数据，它正在工作，但是在传递列表时，它不会在模板中显示任何数据

我尝试检查列表是否为 None 或为空，但不，它不是空的。 谢谢！

Answer 1

你得到了类似的东西（ __str__ of bs4.element.Tag 实例）：

<title>lorem ipsum, dolor...</title>, <link>https://news.google.com/__i/rss/rd/articles/CBMiaGh0dHBzOi8vd3d3LmNubi5jb20vMjAyMC8wMi8wNS9wb2xpdGljcy9kb25hbGQtdHJ1bXAtbmFuY3ktcGVsb3NpLXN0YXRlLW9mLXRoZS11bmlvbi1hbmFseXNpcy9pbmRleC5odG1s0gFsaHR0cHM6Ly9hbXAuY25uLmNvbS9jbm4vMjAyMC8wMi8wNS9wb2xpdGljcy9kb25hbGQtdHJ1bXAtbmFuY3ktcGVsb3NpLXN0YXRlLW9mLXRoZS11bmlvbi1hbmFseXNpcy9pbmRleC5odG1s?oc=5</link>, <guid isPermaLink="false">52780574934659</guid>, <pubDate>Wed, 05 Feb 2020 08:15:00 GMT</pubDate>, <description>&lt;ol&gt;&lt;li&gt;&lt;a href="https://news.google.com/__i/rss/rd/articles/CBMiaGh0dHBzOi8vd3d3LmNubi5jb20vMjAyMC8wMi8wNS9wb2xpdGljcy9kb25hbGQtdHJ1bXAtbmFuY3ktcGVsb3NpLXN0YXRlLW9mLXRoZS11bmlvbi1hbmFseXNpcy9pbmRleC5odG1s0gFsaHR0cHM6Ly9hbXAuY25uLmNvbS9jbm4vMjAyMC8wMi8wNS9wb2xpdGljcy9kb25hbGQtdHJ1bXAtbmFuY3ktcGVsb3NpLXN0YXRlLW9mLXRoZS11bmlvbi1hbmFseXNpcy9pbmRleC5odG1s?oc=5" target="_blank"&gt;Trump makes dazzling, divisive reelection pitch in State of the Union&lt;/a&gt;&amp;nbsp;&amp;nbsp;&lt;font color="#6f6f6f"&gt;CNN&lt;/font&gt;&lt;/li&gt;&lt;li&gt;&lt;a href="https://news.google.com/__i/rss/rd/articles/CBMiK2h0dHBzOi8vd3d3LnlvdXR1YmUuY29tL3dhdGNoP3Y9QlNnYzd3dWlOMzDSAQA?oc=5" target="_blank"&gt;Nancy Pelosi rips up Trump's State of the Union speech&lt;/a&gt;&amp;nbsp;&amp;nbsp;&lt;font color="#6f6f6f"&gt;CNN&lt;/font&gt;&lt;/li&gt;&lt;li&gt;&lt;a href="https://news.google.com/__i/rss/rd/articles/CBMiZWh0dHBzOi8vd3d3Lm5iY25ld3MuY29tL3RoaW5rL29waW5pb24vc3RhdGUtdW5pb24taXNuLXQtc3Ryb25nLXRydW1wLXByZXRlbmRzLWl0LXMtYmV0dGVyLW5jbmExMTI5OTIx0gEtaHR0cHM6Ly93d3cubmJjbmV3cy5jb20vdGhpbmsvYW1wL25jbmExMTI5OTIx?oc=5" target="_blank"&gt;The state of the union isn't as strong as Trump pretends, but it's better than Democrats say&lt;/a&gt;&amp;nbsp;&amp;nbsp;&lt;font color="#6f6f6f"&gt;NBC News&lt;/font&gt;&lt;/li&gt;&lt;li&gt;&lt;a href="https://news.google.com/__i/rss/rd/articles/CBMicWh0dHBzOi8vbnlwb3N0LmNvbS8yMDIwLzAyLzA1L3N0YXRlLW9mLXRoZS11bmlvbi1hZGRyZXNzLXRydW1wLWhpdHMtZ3JhbmQtc2xhbS13aGlsZS1wZWxvc2ktanVzdC1sb29rcy1sb29rcy1zYWQv0gF1aHR0cHM6Ly9ueXBvc3QuY29tLzIwMjAvMDIvMDUvc3RhdGUtb2YtdGhlLXVuaW9uLWFkZHJlc3MtdHJ1bXAtaGl0cy1ncmFuZC1zbGFtLXdoaWxlLXBlbG9zaS1qdXN0LWxvb2tzLWxvb2tzLXNhZC9hbXAv?oc=5" target="_blank"&gt;State of the Union address: Trump hits grand slam, while Pelosi just looks looks sad&lt;/a&gt;&amp;nbsp;&amp;nbsp;&lt;font color="#6f6f6f"&gt;New York Post &lt;/font&gt;&lt;/li&gt;&lt;li&gt;&lt;a href="https://news.google.com/__i/rss/rd/articles/CBMiZmh0dHBzOi8vd3d3LmZveG5ld3MuY29tL29waW5pb24vbGVzbGllLW1hcnNoYWxsLXNvdHUtYWRkcmVzcy1jb250aW51ZXMtdHJ1bXBzLXJvbGUtYXMtZGl2aWRlci1pbi1jaGllZtIBamh0dHBzOi8vd3d3LmZveG5ld3MuY29tL29waW5pb24vbGVzbGllLW1hcnNoYWxsLXNvdHUtYWRkcmVzcy1jb250aW51ZXMtdHJ1bXBzLXJvbGUtYXMtZGl2aWRlci1pbi1jaGllZi5hbXA?oc=5" target="_blank"&gt;Leslie Marshall: SOTU address continues Trump’s role as divider in chief&lt;/a&gt;&amp;nbsp;&amp;nbsp;&lt;font color="#6f6f6f"&gt;Fox News&lt;/font&gt;&lt;/li&gt;&lt;li&gt;&lt;strong&gt;&lt;a href="https://news.google.com/stories/CAAqOQgKIjNDQklTSURvSmMzUnZjbmt0TXpZd1NoTUtFUWlEamE3N2pvQU1FU1YxUEo2emxrYWRLQUFQAQ?oc=5" target="_blank"&gt;View full coverage on Google News&lt;/a&gt;&lt;/strong&gt;&lt;/li&gt;&lt;/ol&gt;</description>, <source url="https://www.cnn.com">CNN</source>

存储在news 。

您无法使用{{ news.title.text }}访问此实例。 这就是为什么您最终在模板中得到一个空结果的原因。 试试 {{ news }} 你会看到里面有什么。

您可以创建一个自定义模板过滤器，它可以从该实例中提取必要的数据 --> https://docs.djangoproject.com/en/3.0/howto/custom-template-tags/

或者你将你的get_news方法中的数据准备成一个get_news的 python 结构list of dicts

工作示例：

def get_news():
    news_link = "https://news.google.com/news/rss"
    page = urlopen(news_link)
    xml_page = page.read()
    page.close()

    soup_page = soup(xml_page, "xml")
    news_list = map(
        lambda item: {'title': item.title.text, 'date': item.pubDate.text},
        soup_page.findAll("item"))
    return news_list

在模板中：

    {% for news in news_list %}
        <h3> {{ news.title }} </h3>
        <h3> {{ news.date }} </h3>
    {% endfor %}

Answer 2

在news_list你得到<class 'bs4.element.ResultSet'>漂亮的汤对象，这就是为什么你可以在视图中打印它而不能在模板中使用它。

您可以使用 feedparser 模块作为替代。

import feedparser
news_link = "https://news.google.com/news/rss"
print(feedparser.parse(news_link))