python - Django：尝试在 URL 中使用 Slug 时出现 404 错误

Question

我是一名初学者，通过构建一个名为 PhoneReview 的应用程序来学习 Django。它将存储与最新手机相关的评论。它还将显示手机品牌，以及相关的手机型号及其评论。

当我去http://127.0.0.1:8000/index时，我看到了这个页面：

当我点击Samsung时，我看到这个页面：

到此为止还好。但是当我点击任何手机型号时，比如Galaxy S10，我会收到 404 错误。它看起来像这样：

Page not found (404)
Request Method: GET
Request URL:    http://127.0.0.1:8000/details/galaxy-s10
Raised by:  PhoneReview.views.ReviewView
No review found matching the query

You're seeing this error because you have DEBUG = True in your Django settings file. Change that to False, and Django will display a standard 404 page.

当我点击三星时，我应该会看到details.html页面，其中包含对手机的评论以及新闻链接。相反，我收到了 404 错误。

这是我位于 PhoneReview 文件夹中的models.py代码：

from django.db import models
from django.template.defaultfilters import slugify

# Create your models here.
class Brand(models.Model):
    brand_name = models.CharField(max_length=100)
    origin = models.CharField(max_length=100)
    manufacturing_since = models.CharField(max_length=100, null=True, blank=True)
    slug = models.SlugField(max_length=150, null=True, blank=True)

    def __str__(self):
        return self.brand_name

    def save(self, *args, **kwargs):
        self.slug = slugify(self.brand_name)
        super().save(*args, **kwargs)

class PhoneModel(models.Model):
    brand = models.ForeignKey(Brand, on_delete=models.CASCADE)
    model_name = models.CharField(max_length=100)
    launch_date = models.CharField(max_length=100)
    platform = models.CharField(max_length=100)
    slug = models.SlugField(max_length=150, null=True, blank=True)

    def __str__(self):
        return self.model_name

    def save(self, *args, **kwargs):
        self.slug = slugify(self.model_name)
        super().save(*args, **kwargs)

class Review(models.Model):
    phone_model = models.ManyToManyField(PhoneModel, related_name='reviews')
    review_article = models.TextField()
    date_published = models.DateField(auto_now=True)
    slug = models.SlugField(max_length=150, null=True, blank=True)
    link = models.TextField(max_length=150, null=True, blank=True)

    def __str__(self):
        return self.review_article

    def save(self, *args, **kwargs):
        self.slug = slugify(self.phone_model)
        super().save(*args, **kwargs)

这是我位于 PhoneReview 文件夹中的urls.py代码：

from . import views
from django.urls import path

app_name = 'PhoneReview'

urlpatterns = [
    path('index', views.BrandListView.as_view(), name='brandlist'),
    path('phonemodel/<slug:slug>', views.ModelView.as_view(), name='modellist'),
    path('details/<slug:slug>', views.ReviewView.as_view(), name='details'),
]

以下是位于 PhoneReview 文件夹中的views.py代码：

from django.shortcuts import render, get_object_or_404
from django.views import generic
from .models import Brand, PhoneModel, Review


class BrandListView(generic.ListView):
    template_name = 'PhoneReview/index.html'
    context_object_name = 'all_brands'

    def get_queryset(self):
        return Brand.objects.all()


class ModelView(generic.ListView):
    template_name = 'PhoneReview/phonemodel.html'
    context_object_name = 'all_model_name'

    def get_queryset(self):
        self.brand = get_object_or_404(Brand, slug=self.kwargs['slug'])
        return PhoneModel.objects.filter(brand=self.brand)

class ReviewView(generic.DetailView):
    model = Review
    template_name = 'PhoneReview/details.html'

以下是位于 PhoneReview 文件夹中的apps.py代码：

from django.apps import AppConfig


class PhonereviewConfig(AppConfig):
    name = 'PhoneReview'

这是我位于模板文件夹内的index.html代码：

{% extends 'PhoneReview/base.html' %}

{% load static %}

{% block title%}
Brand List
{% endblock %}

{% block content %}
<!--Page content-->
<h1>This is Brand List Page</h1>
<h2>Here is the list of the brands</h2>
    <ul>
        {% for brand in all_brands %}
<!--            <li>{{ brand.brand_name }}</li>-->
            <li><a href = "{% url 'PhoneReview:modellist' brand.slug %}">{{ brand.brand_name }}</a></li>
        {% endfor %}
    </ul>
<img src="{% static "images/brandlist.jpg" %}" alt="Super Mario Odyssey" /> <!-- New line -->
{% endblock %}

这是我位于模板文件夹中的phonemodel.html代码：

{% extends 'PhoneReview/base.html' %}

{% load static %}

{% block title%}
Phone Model Page
{% endblock %}

{% block content %}
<!--Page content-->
<h1>This is Phone Model Page</h1>
<h2>Here is the phone model</h2>
    <ul>
        {% for phonemodel in all_model_name %}
            <li><a href = "{% url 'PhoneReview:details' phonemodel.slug %}">{{ phonemodel.model_name }}</a></li>
        {% endfor %}
    </ul>
<img src="{% static "images/brandlist.jpg" %}" alt="Super Mario Odyssey" /> <!-- New line -->
{% endblock %}

这是我位于模板文件夹内的details.html代码：

{% extends 'PhoneReview/base.html' %}
{% load static %}

<html>

<link rel="stylesheet" type="text/css" href="{% static "css/style.css" %}">


<html lang="en">

{% block title%}Details{% endblock %}

{% block content %}

<h1>This is the Details Page</h1>

<h2>Review:</h2>
<p>{{ review.review_article }}</p>

<h2>News Link:</h2>
<p>{{ review.link }}</p>
{% endblock %}
</html>

我对details.html做错了吗？当我<pk>在 urls.py中使用时<slug:slug>，它运行良好。

更新 1：当我尝试通过 Django 管理员添加对手机型号的评论时，我收到此错误： "<Review: The Galaxy S10 is a fitting 10th anniversary phone for Samsung and its storied S series. >" needs to have a value for field "id" before this many-to-many relationship can be used.

更新 2：我已经通过在class Reviewon中删除这些行来解决上述问题models.py：

def save(self, *args, **kwargs): self.slug = slugify(self.phone_model) super().save(*args, **kwargs)

标签： pythondjango