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Python Django Basics Final Details url Tag

Posted by Blaine McCarthy
Blaine McCarthy
17,030 Points

Reverse for 'list' with arguments '()' and keyword arguments '{}' not found. 0 pattern(s) tried: []

Help! I've restarted this whole class twice now because I couldn't get past this - whenever I add a namespace, I immediately receive the error in the subject. Prior to that, all pages and links worked.

The error references the {% url 'courses:list' %} part from layout.html, but that seems fine?

urls.py:

from django.conf.urls import include, url
from django.contrib.staticfiles.urls import staticfiles_urlpatterns
from django.contrib import admin
from . import views

urlpatterns = [
    # Examples:
    # url(r'^$', 'learning_site.views.home', name='home'),
    # url(r'^blog/', include('blog.urls')),

    url(r'^courses/',include('courses.urls',namespace='courses')),
    url(r'^admin/', include(admin.site.urls)),
    url(r'^$',views.home,name='home'),
]
urlpatterns += staticfiles_urlpatterns()

app urls.py

from django.conf.urls import url
from courses import views

urlpatterns = [
    url(r'(?P<course_pk>\d+)/(?P<step_pk>\d+)/$',views.step_detail,name="step"),
    url(r'(?P<pk>\d+)/$',views.course_detail,name="detail"),
    url(r'^$',views.course_list,name="courses"),
]

layout.html:

<!DOCTYPE html>
{% load static from staticfiles %}
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>{% block title %}{% endblock title %}</title>
    <link rel="stylesheet" href="{% static 'css/layout.css' %}">
</head>
<body>
    <div class="site-container">
        <nav>
            <a href="{% url 'home' %}">Home</a>
            <a href="{% url 'courses:list' %}">Course List</a>

        </nav>
    {% block content %}

    {% endblock content %}
    </div>
</body>
</html>

course_list.html

{% extends "layout.html" %}

{% block title %}Available Courses{% endblock title %}

{% block content %}
    <div class="cards">
    {% for course in courses %}
        <div class="card">
            <header><a href="{% url 'courses:detail' pk=course.pk %}">{{course.title}}</a></header>
            <div class="card-copy">
                {{course.description}}
            </div>
        </div>
        {% endfor %}
    </div>


{% endblock content %}

1 Answer

Andreas cormack
.a{fill-rule:evenodd;}techdegree seal-36
Andreas cormack
Python Web Development Techdegree Graduate 33,011 Points

Hi Blaine

You have named the url that lists all the courses in the app.urls as 'courses' , shouldn't this be called 'list'?

urlpatterns = [
    url(r'(?P<course_pk>\d+)/(?P<step_pk>\d+)/$',views.step_detail,name="step"),
    url(r'(?P<pk>\d+)/$',views.course_detail,name="detail"),
    #error is here i think
    url(r'^$',views.course_list,name="courses"),
    # try this
    url(r'^$',views.course_list,name="list"),
]

let me know if this works

Blaine McCarthy
Blaine McCarthy
17,030 Points

omg. That's a little embarrassing.. Thanks Andreas!

Andreas cormack
.a{fill-rule:evenodd;}techdegree seal-36
Andreas cormack
Python Web Development Techdegree Graduate 33,011 Points

Dont worry, i have made so many errors like this

Mihai Dinu
Mihai Dinu
12,763 Points

Thanks, you save my life :)