Django| Reverse for 'user-posts' with arguments '('',)' not found. 1 pattern(s) tried: ['user/(?P[^/]+)$']

Question

I am following django tutorial by @CoreyMSchafer. I got error while practicing i can't find solution to it.

According to my understanding its problem with reversing of url. but can't find out what is wrong

Error: NoReverseMatch at /

Reverse for 'user-posts' with arguments '('',)' not found. 1 pattern(s) tried: ['user/(?P[^/]+)$']

For some reason error is in head of base.html where I'm linking bootstrap.

I also tried removing that link then its giving same error but at line 0 of base.html

views.py:

class UserPostListView(ListView):
    model = Post
    context_object_name = 'posts'
    template_name = 'blog/user_posts.html'

    paginate_by = 5

    def get_queryset(self):
        user = get_object_or_404(User, username=self.kwargs.get('username'))
        return Post.objects.all().filter(author= user).order_by('-date_posted')

urls.py file:

from django.urls import path, include
from .views import PostListView, PostDetailView, PostCreateView, PostUpdateView, PostDeletelView, UserPostListView
from . import views

urlpatterns = [
    path('',                        PostListView.as_view(),         name='blog-home'),
    path('user/',    UserPostListView.as_view(),     name='user-posts'),
    path('post//',          PostDetailView.as_view(),       name='post-detail'),
    path('post/new/',               PostCreateView.as_view(),       name='post-create'),
    path('post//update/',   PostUpdateView.as_view(),       name='post-update'),
    path('post//delete/',   PostDeletelView.as_view(),      name='post-delete'),
    path('about/',                  views.about,                    name='blog-about'),
]

user_posts.html:


    {% if is_paginated %}

      {% if page_obj.has_previous %}
        First
        Previous
      {% endif %}

      {% for num in page_obj.paginator.page_range %}
        {% if page_obj.number == num %}
          {{ num }}
        {% elif num > page_obj.number|add:'-3' and num < page_obj.number|add:'3' %}
          {{ num }}
        {% endif %}
      {% endfor %}

      {% if page_obj.has_next %}
        Next
        Last
      {% endif %}

    {% endif %}
{% endblock content %}

home.html

{% if is_paginated %}

      {% if page_obj.has_previous %}
        First
        Previous
      {% endif %}

      {% for num in page_obj.paginator.page_range %}
        {% if page_obj.number == num %}
          {{ num }}
        {% elif num > page_obj.number|add:'-3' and num < page_obj.number|add:'3' %}
          {{ num }}
        {% endif %}
      {% endfor %}

      {% if page_obj.has_next %}
        Next
        Last
      {% endif %}

    {% endif %}

post_detail.html

{% extends "blog/base.html" %}
{% block content %}

    
        
        
        
            {{ object.author }}
            {{ object.date_posted|date:"M d, Y"}}
            {% if object.author == user %}
                
                    Update
                    Delete
                
            {% endif %}
        
        {{ object.title }}
        {{ object.content }}
        
    

{% endblock content %}

base.html

{% extends "blog/base.html" %}
{% block content %}

    
        
        
        
            {{ object.author }}
            {{ object.date_posted|date:"M d, Y"}}
            {% if object.author == user %}
                
                    Update
                    Delete
                
            {% endif %}
        
        {{ object.title }}
        {{ object.content }}
        
    

{% endblock content %}

user_14031929 · Answer

url(r'^user/(?P\w{0,50})/$', UserPostListView.as_view(), name='user-posts'),

just add it in your url
not this

path('user//', UserPostListView.as_view(),name='user-posts'),

user_14104286 · Answer

I had the same question before. In your user_posts.html and base.html, change all the name of the 'object' stuff to 'post'. Example:

"object.author" -> "post.author", 
"object.title" -> "post.title", 
"object.author.username" -> "post.author.username"

that's a fix for me.

PS: Actually, u didn't post out the above mentioned part of the code. XD

user_12061754 · Answer

In the urls.py file -

path('user//', UserPostListView.as_view(),name='user-posts'),

You forget to add backslash after

user_12971916 · Answer

i was watching the same course and i had the same problem. following two steps made this work for me: first make sure that you are referring to a correct HTML and then add a forward slash after your url like this:

path('user//', UserPostListView.as_view(), name='user-posts'),

if it didnt work for you use url instead of path like this:

url(r'^user/(?P\w{0,50})/$', UserPostListView.as_view(), name='user-posts'),

user_9330353 · Answer

I had the same error . My mistake was I misspelled 'object' in this line posts_detail.html

            {{ object.author }}

this might not be the reason for your error, but anyone else stuck with this error check for typos in your HTML files.

user_6513055 · Answer

Replace post.author.username with post.author. It helped me.

Django| Reverse for 'user-posts' with arguments '('',)' not found. 1 pattern(s) tried: ['user/(?P<username>[^/]+)$']

6 Answers