Writing Your First Django App, part 3: server broken after trying to edit URL

Using Django Getting Started
1

On part 3 of the tutorial, I got down to “Removing hardcoded URLs in templates”. I tried changing the name of the polls detail view to “custom”, but when I tried accessing the server using /custom, I got the following error:

Page not found (404)
Request Method:	GET
Request URL:	http://127.0.0.1:8000/polls/custom/
Using the URLconf defined in mysite.urls, Django tried these URL patterns, in this order:

polls/ [name='index']
polls/ custom/<int:question_id>/ [name='custom']
polls/ <int:question_id>/results/ [name='results']
polls/ <int:question_id>/vote/ [name='vote']
admin/
The current path, polls/custom/, didn’t match any of these.

I did some troubleshooting and ended up changing the function name for the view in views.py, but it didn’t resolve the error. I then changed a few other things (I can’t remember what exactly), it still didn’t work, then I ended up changing “custom” back to the original “detail”. However, now I get a different error when trying to access the server:

# Page not found (404)

|Request Method:|GET|
| --- | --- |
|Request URL:|http://127.0.0.1:8000/|

Using the URLconf defined in `mysite.urls`, Django tried these URL patterns, in this order:

1. polls/
2. admin/

The empty path didn’t match any of these.

Clearly I’m missing something, or I unwittingly edited something while troubleshooting that has broken access to the entire server.

2

Post your urls.py, your views.py and your template code in order to get better help.

3

urls.py

from django.urls import path

from . import views

urlpatterns = [
    path("", views.index, name="index"),
    path("<int:question_id>/", views.detail, name="detail"),
    path("<int:question_id>/results/", views.results, name="results"),
    path("<int:question_id>/vote/", views.vote, name="vote"),
]

views.py

from django.http import HttpResponse
from django.http import Http404
from django.shortcuts import get_object_or_404, render

from .models import Question

'''
def index(request):
    return HttpResponse("Hello, world. You're at the polls index.")'''

def index(request):
    latest_question_list = Question.objects.order_by("-pub_date")[:5]
    context = {"latest_question_list": latest_question_list}
    return render(request, "polls/index.html", context)
    #output = ", ".join([q.question_text for q in latest_question_list])
    return HttpResponse(template.render(context, request))

def detail(request, question_id):
    question = get_object_or_404(Question, pk=question_id)
    return render(request, "polls/detail.html", {"question": question})


def results(request, question_id):
    response = "You're looking at the results of question %s."
    return HttpResponse(response % question_id)


def vote(request, question_id):
    return HttpResponse("You're voting on question %s." % question_id)

templates

detail.html

{h1}{{ question.question_text }}</h1>
<ul>
{% for choice in question.choice_set.all %}
    <li>{{ choice.choice_text }}</li>
{% endfor %}
</ul>

index.html

{h1}{{ question.question_text }}</h1>
<ul>
{% for choice in question.choice_set.all %}
    <li>{{ choice.choice_text }}</li>
{% endfor %}
</ul>
4

The name “custom” is used within your Django code to create the url. You do not use that name as a url in your browser.

You should roll your changes back to the point where you were when you made this change.

5

2 Questions.

  1. I thought the whole point of doing this was to change the URL itself? If not, what is the purpose of doing this?
  2. How do I roll back to a previous state?
6

You need a version control system like git

7

The full description is at Removing hardcoded URLs in templates. Briefly, it’s exactly what the title describes, you’re removing full hard-coded urls from your templates. It does not change the urls themselves.

That depends upon whether you’re using a version control system like git, or if your editor / IDE maintains file history, or if your editor’s undo function tracks these recent changes back far enough.