URL parameter type converters in Django - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ component_behavior

intermediate

What is the output of this Django URL pattern matching?

Given the URL pattern and view below, what will be the value of year inside the view when the URL /archive/2023/ is accessed?

Django

from django.urls import path
from django.http import HttpResponse

def archive_view(request, year):
    return HttpResponse(f"Year: {year}")

urlpatterns = [
    path('archive/<int:year>/', archive_view),
]

A "Year: 2023"

B "Year: '2023'" (string with quotes)

C "Year: 2023.0" (float value)

D Raises a ValueError because year is not converted

💡 Hint

The int converter converts the URL part to an integer type.

The <int:year> converter converts the URL segment to an integer before passing it to the view. So, year is an integer 2023, and the response is Year: 2023.

📝 Syntax

intermediate

Which URL pattern correctly uses the slug converter?

Select the URL pattern that correctly captures a slug parameter named post_slug.

A path('post/<slug_post>/', views.post_detail)

B path('post/<slug:post_slug>/', views.post_detail)

C path('post/<str:post_slug>/', views.post_detail)

D path('post/<slug>/', views.post_detail)

💡 Hint

The syntax is <converter:name>.

The correct syntax for a slug converter is <slug:post_slug>. Option B uses str converter which is valid but not slug. Option B and D have incorrect parameter names or missing converter.

🔧 Debug

advanced

Why does this URL pattern cause a 404 error for /user/abc123/?

Consider this URL pattern:

path('user//', views.user_profile)

Why does accessing /user/abc123/ return a 404 error?

A Because the user_id parameter is not passed as a string

B Because the view function is missing a required argument

C Because the URL pattern is missing a trailing slash

D Because 'abc123' is not a valid integer, so the pattern does not match

💡 Hint

The int converter only matches digits.

The <int:user_id> converter only matches digits. The string 'abc123' contains letters, so the URL pattern does not match and Django returns 404.

❓ state_output

advanced

What is the type and value of pk in this view?

Given this URL pattern and view:

path('item//', views.item_detail)

def item_detail(request, pk):
    return HttpResponse(type(pk).__name__ + ' ' + str(pk))

What will be the response content when accessing /item/123e4567-e89b-12d3-a456-426614174000/?

A "int 123e4567"

B "str 123e4567-e89b-12d3-a456-426614174000"

C "UUID 123e4567-e89b-12d3-a456-426614174000"

D Raises a ValueError because UUID is not converted

💡 Hint

The uuid converter converts the string to a UUID object.

The <uuid:pk> converter converts the URL string to a UUID object. So, pk is a UUID instance, and type(pk).__name__ is 'UUID'.

🧠 Conceptual

expert

Which statement about Django URL converters is true?

Select the correct statement about Django's built-in URL parameter type converters.

A The <code>slug</code> converter matches only letters, numbers, underscores, and hyphens

B The <code>path</code> converter matches any non-empty string including slashes

C The <code>int</code> converter matches any integer including negative numbers

D The <code>uuid</code> converter matches only lowercase hexadecimal digits without hyphens

💡 Hint

Think about what characters a slug can contain.

The slug converter matches ASCII letters, numbers, underscores, and hyphens. The path converter matches any non-empty string including slashes. The int converter matches only positive integers (digits). The uuid converter matches UUID strings with hyphens and both uppercase and lowercase hex digits.