.NoReverseMatch：未找到参数为 '('',)' 的 'author-detail' 反转。尝试了 1 个模式：['目录/作者/(?P<pk> [0-9]+)$']

Question

Many people have already ask similar question to this, but I still cannot figure out the solution unfortunately.很多人已经问过类似的问题，但不幸的是我仍然找不到解决方案。 I am doing a django tutorial from https://developer.mozilla.org/en-US/docs/Learn/Server-side/Django/Tutorial_local_library_website .我正在做一个来自https://developer.mozilla.org/en-US/docs/Learn/Server-side/Django/Tutorial_local_library_website的 Django 教程。 I compared my code with their's on Github but I do not see the difference.我将我的代码与 Github 上的代码进行了比较，但我看不出有什么区别。 The current state of my code is here https://github.com/diveki/webdev/tree/master/django_projects/locallibrary it works well except for showing the details of the Author model.我的代码的当前状态在这里https://github.com/diveki/webdev/tree/master/django_projects/locallibrary除了显示作者模型的详细信息外，它运行良好。

The error message I get is: django.urls.exceptions.NoReverseMatch: Reverse for 'author-detail' with arguments '('',)' not found. 1 pattern(s) tried: ['catalog/author/(?P<pk>[0-9]+)$']我得到的错误消息是： django.urls.exceptions.NoReverseMatch: Reverse for 'author-detail' with arguments '('',)' not found. 1 pattern(s) tried: ['catalog/author/(?P<pk>[0-9]+)$'] django.urls.exceptions.NoReverseMatch: Reverse for 'author-detail' with arguments '('',)' not found. 1 pattern(s) tried: ['catalog/author/(?P<pk>[0-9]+)$'] . django.urls.exceptions.NoReverseMatch: Reverse for 'author-detail' with arguments '('',)' not found. 1 pattern(s) tried: ['catalog/author/(?P<pk>[0-9]+)$'] 。

The full error that django gives when I click on the Author list items:当我单击作者列表项时 django 给出的完整错误：

NoReverseMatch at /catalog/author/1
Reverse for 'author-detail' with arguments '('',)' not found. 1 pattern(s) tried: ['catalog/author/(?P<pk>[0-9]+)$']
Request Method: GET
Request URL:    http://127.0.0.1:8000/catalog/author/1
Django Version: 3.0.4
Exception Type: NoReverseMatch
Exception Value:    
Reverse for 'author-detail' with arguments '('',)' not found. 1 pattern(s) tried: ['catalog/author/(?P<pk>[0-9]+)$']
Exception Location: C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\urls\resolvers.py in _reverse_with_prefix, line 677
Python Executable:  C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\python.exe
Python Version: 3.7.3
Python Path:    
['C:\\Users\\divekizs\\Python\\Scripts\\WebDev\\django_projects\\locallibrary',
 'C:\\Users\\divekizs\\AppData\\Local\\Continuum\\anaconda3\\envs\\django\\python37.zip',
 'C:\\Users\\divekizs\\AppData\\Local\\Continuum\\anaconda3\\envs\\django\\DLLs',
 'C:\\Users\\divekizs\\AppData\\Local\\Continuum\\anaconda3\\envs\\django\\lib',
 'C:\\Users\\divekizs\\AppData\\Local\\Continuum\\anaconda3\\envs\\django',
 'C:\\Users\\divekizs\\AppData\\Local\\Continuum\\anaconda3\\envs\\django\\lib\\site-packages',
 'C:\\Users\\divekizs\\AppData\\Local\\Continuum\\anaconda3\\envs\\django\\lib\\site-packages\\win32',
 'C:\\Users\\divekizs\\AppData\\Local\\Continuum\\anaconda3\\envs\\django\\lib\\site-packages\\win32\\lib',
 'C:\\Users\\divekizs\\AppData\\Local\\Continuum\\anaconda3\\envs\\django\\lib\\site-packages\\Pythonwin']
Server time:    Wed, 18 Mar 2020 18:34:15 +0100

Traceback:追溯：

Environment:


Request Method: GET
Request URL: http://127.0.0.1:8000/catalog/author/1

Django Version: 3.0.4
Python Version: 3.7.3
Installed Applications:
['django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'catalog']
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.messages.middleware.MessageMiddleware',
 'django.middleware.clickjacking.XFrameOptionsMiddleware']


Template error:
In template C:\Users\divekizs\Python\Scripts\WebDev\django_projects\locallibrary\catalog\templates\base_generic.html, error at line 6
   Reverse for 'author-detail' with arguments '('',)' not found. 1 pattern(s) tried: ['catalog/author/(?P<pk>[0-9]+)$']
   1 : <!DOCTYPE html>
   2 : <html lang="en">
   3 : <head>
   4 :   {% block title %}<title>Local Library</title>{% endblock %}
   5 :   <meta charset="utf-8">
   6 :   <meta name="viewport" co ntent="width=device-width, initial-scale=1" >
   7 :   <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" integrity="sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" crossorigin="anonymous">
   8 :   <!-- Add additional CSS in static file -->
   9 :   {% load static %}
   10 :   <link rel="stylesheet" href="{% static 'css/styles.css' %}">
   11 : </head>
   12 : <body>
   13 :   <div class="container-fluid">
   14 :     <div class="row">
   15 :       <div class="col-sm-2">
   16 :       {% block sidebar %}


Traceback (most recent call last):
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\core\handlers\exception.py", line 34, in inner
    response = get_response(request)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\core\handlers\base.py", line 145, in _get_response
    response = self.process_exception_by_middleware(e, request)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\core\handlers\base.py", line 143, in _get_response
    response = response.render()
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\response.py", line 105, in render
    self.content = self.rendered_content
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\response.py", line 83, in rendered_content
    return template.render(context, self._request)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\backends\django.py", line 61, in render
    return self.template.render(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\base.py", line 171, in render
    return self._render(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\base.py", line 163, in _render
    return self.nodelist.render(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\base.py", line 936, in render
    bit = node.render_annotated(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\base.py", line 903, in render_annotated
    return self.render(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\loader_tags.py", line 150, in render
    return compiled_parent._render(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\base.py", line 163, in _render
    return self.nodelist.render(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\base.py", line 936, in render
    bit = node.render_annotated(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\base.py", line 903, in render_annotated
    return self.render(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\loader_tags.py", line 62, in render
    result = block.nodelist.render(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\base.py", line 936, in render
    bit = node.render_annotated(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\base.py", line 903, in render_annotated
    return self.render(context)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\template\defaulttags.py", line 443, in render
    url = reverse(view_name, args=args, kwargs=kwargs, current_app=current_app)
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\urls\base.py", line 87, in reverse
    return iri_to_uri(resolver._reverse_with_prefix(view, prefix, *args, **kwargs))
  File "C:\Users\divekizs\AppData\Local\Continuum\anaconda3\envs\django\lib\site-packages\django\urls\resolvers.py", line 677, in _reverse_with_prefix
    raise NoReverseMatch(msg)

Exception Type: NoReverseMatch at /catalog/author/1
Exception Value: Reverse for 'author-detail' with arguments '('',)' not found. 1 pattern(s) tried: ['catalog/author/(?P<pk>[0-9]+)$']

I do not copy here all the code I wrote for this (unless you need it), but here is my models.py , urls.py from catalog , the relevant code from views.py and the templates:我不会在这里复制我为此编写的所有代码（除非您需要它），但这里是我的models.py 、 catalog urls.py 、 views.py的相关代码和模板：

Part of my catalog/models.py :我的catalog/models.py ：

from django.db import models
from django.urls import reverse # Used to generate URLs by reversing the URL patterns
import uuid # Required for unique book instances

class Author(models.Model):
    """Model representing an author."""
    first_name = models.CharField(max_length=100)
    last_name = models.CharField(max_length=100)
    date_of_birth = models.DateField(null=True, blank=True)
    date_of_death = models.DateField('died', null=True, blank=True)

    class Meta:
        ordering = ['last_name', 'first_name']

    def get_absolute_url(self):
        """Returns the url to access a particular author instance."""
        return reverse('author-detail', args=[str(self.id)])

    def __str__(self):
        """String for representing the Model object."""
        return '{0}, {1}'.format(self.last_name, self.first_name)

catalog/urls.py : catalog/urls.py ：

from django.urls import path
from . import views

urlpatterns = [
    path('', views.index, name='index'),
    path('books/', views.BookListView.as_view(), name='books'),
    path('book/<int:pk>', views.BookDetailView.as_view(), name='book-detail'),
    path('authors/', views.AuthorListView.as_view(), name='authors'),
    path('author/<int:pk>',
         views.AuthorDetailView.as_view(), name='author-detail'),
]

Complete catalog/views.py :完整的catalog/views.py ：

from django.shortcuts import render
from catalog.models import Book, Author, BookInstance, Genre
from django.views import generic

# Create your views here.
def index(request):
    num_books = Book.objects.all().count()
    num_instances = BookInstance.objects.all().count()

    #Available Books
    num_instances_available = BookInstance.objects.filter(status__exact='a').count()
    num_authors = Author.objects.count()
    biography_num = Book.objects.filter(genre__name__icontains='horror').count()

    context = {
        'filtered': biography_num,
        'title': 'Changed from index view',
        'num_books': num_books,
        'num_instances': num_instances,
        'num_instances_available': num_instances_available,
        'num_authors': num_authors,
    }

    return render(request, 'index.html', context=context)

class BookListView(generic.ListView):
    model = Book
    paginate_by = 5
    # context_object_name = 'book_list'
    # queryset = Book.objects.filter(title__icontains='zsolt')[:5]
   # 


class BookDetailView(generic.DetailView):
    model = Book
    # context_object_name = 'details'
    # template_name = 'catalog/book_detail.html'


class AuthorListView(generic.ListView):
    model = Author
    paginate_by = 5


class AuthorDetailView(generic.DetailView):
    model = Author

And finally here are the templates:最后是模板：

catalog/templates/base_generic.html : catalog/templates/base_generic.html ：

<!DOCTYPE html>
<html lang="en">
<head>
  {% block title %}<title>Local Library</title>{% endblock %}
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" integrity="sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" crossorigin="anonymous">
  <!-- Add additional CSS in static file -->
  {% load static %}
  <link rel="stylesheet" href="{% static 'css/styles.css' %}">
</head>
<body>
  <div class="container-fluid">
    <div class="row">
      <div class="col-sm-2">
      {% block sidebar %}
        <ul class="sidebar-nav">
          <li><a href="{% url 'index' %}">Home</a></li>
          <li><a href="{% url 'books' %}">All books</a></li>
          <li><a href="{% url 'authors' %}">All authors</a></li>
        </ul>
     {% endblock %}
      </div>
      <div class="col-sm-10 ">{% block content %}{% endblock %}
        {% block pagination %}
        {% if is_paginated %}
          <div class="pagination">
            <span class="page-links">
              {% if page_obj.has_previous %}
                <a href="{{ request.path }}?page={{ page_obj.previous_page_number }}">previous</a>
              {% endif %}
              <span class="page-current">
                Page {{ page_obj.number }} of {{ page_obj.paginator.num_pages }}.
              </span>
              {% if page_obj.has_next %}
                <a href="{{ request.path }}?page={{ page_obj.next_page_number }} ">next</a>
              {% endif %}
            </span>
          </div>
        {% endif %}
      {% endblock %}
      </div>
    </div>
  </div>
</body>
</html>

catalog/templates/catalog/book_details.html : catalog/templates/catalog/book_details.html ：

{% extends "base_generic.html" %}

{% block content %}
  <h1>Title: {{ book.title }}</h1>

  <p><strong>Author:</strong> <a href="{% url 'author-detail' book.author.pk %}">{{ book.author }}</a></p> <!-- author detail link not yet defined -->
  <p><strong>Summary:</strong> {{ book.summary }}</p>
  <p><strong>ISBN:</strong> {{ book.isbn }}</p> 
  <p><strong>Language:</strong> {{ book.language }}</p>  
  <p><strong>Genre:</strong> {{ book.genre.all|join:", " }}</p>   

  <div style="margin-left:20px;margin-top:20px">
    <h4>Copies</h4>

    {% for copy in book.bookinstance_set.all %}
      <hr>
      <p class="{% if copy.status == 'a' %}text-success{% elif copy.status == 'm' %}text-danger{% else %}text-warning{% endif %}">
        {{ copy.get_status_display }}
      </p>
      {% if copy.status != 'a' %}
        <p><strong>Due to be returned:</strong> {{ copy.due_back }}</p>
      {% endif %}
      <p><strong>Imprint:</strong> {{ copy.imprint }}</p>
      <p class="text-muted"><strong>Id:</strong> {{ copy.id }}</p>
    {% endfor %}
  </div>
{% endblock %}

catalog/templates/catalog/book_list.html : catalog/templates/catalog/book_list.html ：

{% extends "base_generic.html" %}

{% block content %}
  <h1>Book List</h1>
  {% if book_list %}
  <ul>
    {% for book in book_list %}
      <li>
        <a href="{{ book.get_absolute_url }}">{{ book.title }}</a> ({{ book.author }}) {{ book.get_absolute_url }}
      </li>
    {% endfor %}
  </ul>
  {% else %}
    <p>There are no books in the library.</p>
  {% endif %}       
{% endblock %}

catalog/templates/catalog/author_list.html : catalog/templates/catalog/author_list.html ：

{% extends "base_generic.html" %}

{% block content %}

<h1>Author List</h1>

{% if author_list %}
  <ul>

  {% for author in author_list %}
    <li>
      <a href="{{ author.get_absolute_url }}">
      {{ author }} ({{author.date_of_birth}} - {% if author.date_of_death %}{{author.date_of_death}}{% endif %})
      </a>
    </li>
  {% endfor %}

 </ul>
{% else %}
  <p>There are no authors available.</p>
{% endif %}



{% endblock %}

catalog/templates/catalog/author_detail.html : catalog/templates/catalog/author_detail.html ：

{% extends "base_generic.html" %}

{% block content %}
hello
{% endblock %}

The problem is that author_detail.html does not show up because django cannot reverse the 'author-detail' name.问题是author_detail.html没有显示，因为 django 无法反转'author-detail'名称。 I know that the {{ author.get_absolute_url }} gives the right url back. I did everything in the same way for the Book model and the我知道{{ author.get_absolute_url }} gives the right url back. I did everything in the same way for the Book model and the {{ author.get_absolute_url }} gives the right url back. I did everything in the same way for the Book model and the book_list.html and book_detail.html` work fine. {{ author.get_absolute_url }} gives the right url back. I did everything in the same way for the Book model and the book_list.html and book_detail.html` 工作正常。

Could you please help me resolve the issue?你能帮我解决这个问题吗？

Answer 1

It seems like the get_absolute_url is not returning the correct value似乎get_absolute_url没有返回正确的值

def get_absolute_url(self): """Returns the url to access a particular author instance.""" return reverse('author-detail', args=[str(self.id)])

I would try something more along the lines of我会尝试更多的东西

def get_absolute_url(self, pk): author = Author.objects.get(pk=pk) return reverse('author-detail', args=pk ) def get_absolute_url(self, pk): author = Author.objects.get(pk=pk) return reverse('author-detail', args=pk )

how to redirect a url with pk to url with pk and slug in django? 如何将带有 pk 的 url 重定向到带有 pk 和 slug 的 django 的 url？

.NoReverseMatch：未找到参数为 '('',)' 的 'author-detail' 反转。尝试了 1 个模式：['目录/作者/(?P<pk> [0-9]+)$']

问题描述

1 个解决方案

解决方案1
0 2020-03-18 17:17:36

.NoReverseMatch：未找到参数为 &#39;(&#39;&#39;,)&#39; 的 &#39;author-detail&#39; 反转。 尝试了 1 个模式：[&#39;目录/作者/(?P<pk> [0-9]+)$&#39;]

问题描述

1 个解决方案

解决方案1 0 2020-03-18 17:17:36

.NoReverseMatch：未找到参数为 '('',)' 的 'author-detail' 反转。尝试了 1 个模式：['目录/作者/(?P<pk> [0-9]+)$']

解决方案1
0 2020-03-18 17:17:36