Reverse for 'post-list' not found. 'post-list' is not a valid view function or pattern name

Question

I'm still within the very early stages of learning Django and I have just ran in to this error (I am following a tutorial, not too sure where I've messed up!)

"Reverse for 'post-list' not found. 'post-list' is not a valid view function or pattern name."

In my template file here is how my template tag looks:

{% if user.is_authenticated %}
    href="{% url 'post-list' %}" 
    {% else %}

As for my URLs.py:

urlpatterns = [
    path('', PostListView.as_view(), name='post-list'),
    path('post/<int:pk>/', PostDetailView.as_view(), name='post-detail'),
    path('post/edit/<int:pk>/', PostEditView.as_view(), name='post-edit'),
    path('post/delete/<int:pk>/', PostDeleteView.as_view(), name='post-delete'),
    path('post/<int:post_pk>/comment/delete/<int:pk>/', CommentDeleteView.as_view(), name='comment-delete'),
    path('post/<int:post_pk>/comment/<int:pk>/like', AddCommentLike.as_view(), name='comment-like'),
    path('post/<int:post_pk>/comment/<int:pk>/dislike', AddCommentDislike.as_view(), name='comment-dislike'),
    path('post/<int:post_pk>/comment/<int:pk>/reply', CommentReplyView.as_view(), name='comment-reply'),
    path('post/<int:pk>/like', AddLike.as_view(), name='like'),
    path('post/<int:pk>/dislike', AddDislike.as_view(), name='dislike'),
    path('profile/<int:pk>/', ProfileView.as_view(), name='profile'),
    path('profile/edit/<int:pk>/', ProfileEditView.as_view(), name='profile-edit'),
    path('profile/<int:pk>/followers/', ListFollowers.as_view(), name='list-followers'),
    path('profile/<int:pk>/followers/add', AddFollower.as_view(), name='add-follower'),
    path('profile/<int:pk>/followers/remove', RemoveFollower.as_view(), name='remove-follower'),
    path('search/', UserSearch.as_view(), name='profile-search'),
    path('notification/<int:notification_pk>/post/<int:post_pk>', PostNotification.as_view(), name='post-notification'),
    path('notification/<int:notification_pk>/profile/<int:profile_pk>', FollowNotification.as_view(), name='follow-notification'),
    path('notification/<int:notification_pk>/thread/<int:object_pk>', ThreadNotification.as_view(), name='thread-notification'),
    path('notification/delete/<int:notification_pk>', RemoveNotification.as_view(), name='notification-delete'),
    path('inbox/', ListThreads.as_view(), name='inbox'),
    path('inbox/create-thread/', CreateThread.as_view(), name='create-thread'),
    path('inbox/<int:pk>/', ThreadView.as_view(), name='thread'),
    path('inbox/<int:pk>/create-message/', CreateMessage.as_view(), name='create-message'),
]

EDIT: Traceback provided below:

Environment:


Request Method: GET
Request URL: http://*/

Django Version: 3.2.2
Python Version: 3.6.8
Installed Applications:
['social',
 'core',
 'crispy_forms',
 'allauth',
 'allauth.account',
 'allauth.socialaccount',
 'django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'django.contrib.sites']
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 /home/myapp/core/templates/landing/navbar.html, error at line 11
   Reverse for 'post-list' not found. 'post-list' is not a valid view function or pattern name.
   1 : {% load custom_tags %}
   2 : 
   3 : <div class="container">
   4 : <nav class="navbar navbar-expand-lg navbar-light">
   5 :   <div class="container-fluid">
   6 :     <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarTogglerDemo03" aria-controls="navbarTogglerDemo03" aria-expanded="false" aria-label="Toggle navigation">
   7 :       <span class="navbar-toggler-icon"></span>
   8 :     </button>
   9 :     <a class="navbar-brand" 
   10 :     {% if user.is_authenticated %}
   11 :     href=" {% url 'post-list' %} " 
   12 :     {% else %}
   13 :     href="{% url 'index' %}"
   14 :     {% endif %}
   15 : 
   16 :     ><i class="fas fa-comment"></i> Social Network</a>
   17 :     <div class="collapse navbar-collapse" id="navbarTogglerDemo03">
   18 :       <ul class="navbar-nav me-auto mb-2 mb-lg-0">
   19 :       </ul>
   20 :       <form class="d-flex" method="GET" action="">
   21 :         <div class="input-group">


Traceback (most recent call last):
  File "/usr/local/lib64/python3.6/site-packages/django/core/handlers/exception.py", line 47, in inner
    response = get_response(request)
  File "/usr/local/lib64/python3.6/site-packages/django/core/handlers/base.py", line 181, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "/usr/local/lib64/python3.6/site-packages/django/views/generic/base.py", line 70, in view
    return self.dispatch(request, *args, **kwargs)
  File "/usr/local/lib64/python3.6/site-packages/django/views/generic/base.py", line 98, in dispatch
    return handler(request, *args, **kwargs)
  File "/home/myapp/core/views.py", line 6, in get
    return render(request, 'landing/index.html')
  File "/usr/local/lib64/python3.6/site-packages/django/shortcuts.py", line 19, in render
    content = loader.render_to_string(template_name, context, request, using=using)
  File "/usr/local/lib64/python3.6/site-packages/django/template/loader.py", line 62, in render_to_string
    return template.render(context, request)
  File "/usr/local/lib64/python3.6/site-packages/django/template/backends/django.py", line 61, in render
    return self.template.render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 170, in render
    return self._render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 162, in _render
    return self.nodelist.render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 938, in render
    bit = node.render_annotated(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 905, in render_annotated
    return self.render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/loader_tags.py", line 150, in render
    return compiled_parent._render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 162, in _render
    return self.nodelist.render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 938, in render
    bit = node.render_annotated(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 905, in render_annotated
    return self.render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/loader_tags.py", line 195, in render
    return template.render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 172, in render
    return self._render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 162, in _render
    return self.nodelist.render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 938, in render
    bit = node.render_annotated(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 905, in render_annotated
    return self.render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/defaulttags.py", line 312, in render
    return nodelist.render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 938, in render
    bit = node.render_annotated(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/base.py", line 905, in render_annotated
    return self.render(context)
  File "/usr/local/lib64/python3.6/site-packages/django/template/defaulttags.py", line 446, in render
    url = reverse(view_name, args=args, kwargs=kwargs, current_app=current_app)
  File "/usr/local/lib64/python3.6/site-packages/django/urls/base.py", line 86, in reverse
    return resolver._reverse_with_prefix(view, prefix, *args, **kwargs)
  File "/usr/local/lib64/python3.6/site-packages/django/urls/resolvers.py", line 694, in _reverse_with_prefix
    raise NoReverseMatch(msg)

Exception Type: NoReverseMatch at /
Exception Value: Reverse for 'post-list' not found. 'post-list' is not a valid view function or pattern name.

Updated (root) URLs.py

"""socialnetwork URL Configuration

The `urlpatterns` list routes URLs to views. For more information please see:
    https://docs.djangoproject.com/en/2.1/topics/http/urls/
Examples:
Function views
    1. Add an import:  from my_app import views
    2. Add a URL to urlpatterns:  path('', views.home, name='home')
Class-based views
    1. Add an import:  from other_app.views import Home
    2. Add a URL to urlpatterns:  path('', Home.as_view(), name='home')
Including another URLconf
    1. Import the include() function: from django.urls import include, path
    2. Add a URL to urlpatterns:  path('blog/', include('blog.urls'))
"""
from django.contrib import admin
from django.urls import path, include
from django.conf import settings
from django.conf.urls.static import static

urlpatterns = [
    path('admin/', admin.site.urls),
    path('', include('core.urls')),
    path('accounts/', include('allauth.urls')),
    path('social/', include('social.urls')),
]

if settings.DEBUG:
    urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)

Could anyone give me any pointers with this?

Thanks, Jay.

Answer 1

Based on your comments, you defined the path in the urls.py of the social module. As a result there is no path from the "root url" to the url that triggers the post-list view, and thus it can not determine the path of that view name.

You should include this, for example with:

urlpatterns = [
    path('admin/', admin.site.urls)
  , path('', include('core.urls'))
  , path('accounts/', include('allauth.urls'))
  , path('social/', include('social.urls'))
]