View decorators (require_GET, require_POST) in Django - Mini Project: Build & Apply

Using Django View Decorators require_GET and require_POST

📖 Scenario: You are building a simple Django web app that handles user requests differently based on whether the request is a GET or a POST.For example, a GET request will show a welcome message, and a POST request will process form data.

🎯 Goal: Create two Django view functions named welcome_view and submit_view. Use the require_GET decorator on welcome_view to allow only GET requests, and use the require_POST decorator on submit_view to allow only POST requests.

📋 What You'll Learn

Create a Django view function called welcome_view that returns an HttpResponse with the text 'Welcome to the site!'

Create a Django view function called submit_view that returns an HttpResponse with the text 'Form submitted successfully!'

Use the require_GET decorator on welcome_view

Use the require_POST decorator on submit_view

💡 Why This Matters

🌍 Real World

Web developers often need to restrict views to specific HTTP methods to ensure correct behavior and security, such as only allowing form submissions via POST.

💼 Career

Understanding and using Django view decorators like require_GET and require_POST is essential for backend web development roles using Django.

1

Create the initial Django view functions

Create two Django view functions named welcome_view and submit_view. Each should take a request parameter and return an HttpResponse with the exact text 'Welcome to the site!' for welcome_view and 'Form submitted successfully!' for submit_view. Import HttpResponse from django.http.

Django

from django.http import HttpResponse

# Create welcome_view function
# Create submit_view function

Hint

Remember to import HttpResponse from django.http. Define two functions with the exact names and return the specified text.

2

Import the decorators require_GET and require_POST

Add import statements to import require_GET and require_POST from django.views.decorators.http.

Django

from django.http import HttpResponse
# Import require_GET and require_POST decorators here

def welcome_view(request):
    return HttpResponse('Welcome to the site!')

def submit_view(request):
    return HttpResponse('Form submitted successfully!')

Hint

Use a single import line to import both require_GET and require_POST from django.views.decorators.http.

3

Apply the require_GET decorator to welcome_view

Add the @require_GET decorator above the welcome_view function definition to allow only GET requests.

Django

from django.http import HttpResponse
from django.views.decorators.http import require_GET, require_POST

# Add @require_GET decorator here

def welcome_view(request):
    return HttpResponse('Welcome to the site!')

def submit_view(request):
    return HttpResponse('Form submitted successfully!')

Hint

Place @require_GET directly above the welcome_view function definition.

4

Apply the require_POST decorator to submit_view

Add the @require_POST decorator above the submit_view function definition to allow only POST requests.

Django

from django.http import HttpResponse
from django.views.decorators.http import require_GET, require_POST

@require_GET
def welcome_view(request):
    return HttpResponse('Welcome to the site!')

# Add @require_POST decorator here

def submit_view(request):
    return HttpResponse('Form submitted successfully!')

Hint

Place @require_POST directly above the submit_view function definition.

Practice

1. What is the main purpose of the @require_GET decorator in Django views?

easy

A. To allow only GET requests to access the view

B. To allow only POST requests to access the view

C. To allow both GET and POST requests to access the view

D. To disable all HTTP requests to the view

Solution

1. Step 1: Understand the decorator's role

   The @require_GET decorator restricts the view to accept only GET requests.

2. Step 2: Compare with other decorators

   Unlike @require_POST which allows only POST, @require_GET is specific to GET requests.

3. Final Answer:

   To allow only GET requests to access the view -> Option A

4. Quick Check:

   @require_GET = allows GET only [OK]

Hint: Remember GET is for reading data, require_GET allows only that [OK]

Common Mistakes:

• Confusing @require_GET with @require_POST
• Thinking it allows all request types
• Assuming it disables the view

2. Which of the following is the correct way to import and use the @require_POST decorator in a Django view?

easy

A. from django.views.decorators import require_POST

@require_POST
def my_view(request):
pass

B. from django.views.decorators.http import require_GET

@require_POST
def my_view(request):
pass

C. from django.http import require_POST

@require_POST
def my_view(request):
pass

D. from django.views.decorators.http import require_POST

@require_POST
def my_view(request):
pass

Solution

1. Step 1: Identify the correct import path

   The @require_POST decorator is imported from django.views.decorators.http.

2. Step 2: Check usage syntax

   The decorator is applied directly above the view function with @require_POST.

3. Final Answer:

   from django.views.decorators.http import require_POST @require_POST def my_view(request): pass -> Option D

4. Quick Check:

   Correct import and decorator usage = from django.views.decorators.http import require_POST @require_POST def my_view(request): pass [OK]

Hint: Import from django.views.decorators.http for both decorators [OK]

Common Mistakes:

• Importing from wrong module like django.http
• Using @require_GET instead of @require_POST
• Missing the decorator above the function

3. Consider this Django view code snippet:

from django.views.decorators.http import require_GET
from django.http import HttpResponse

@require_GET
def sample_view(request):
    return HttpResponse('Hello GET')

What will happen if a POST request is sent to sample_view?

medium

A. The view will return 'Hello GET' response

B. The view will raise a 405 Method Not Allowed error

C. The view will ignore the POST and treat it as GET

D. The view will crash with a server error

Solution

1. Step 1: Understand @require_GET behavior

   The decorator allows only GET requests; other methods are blocked.

2. Step 2: Check response to disallowed methods

   When a POST request is sent, Django returns a 405 Method Not Allowed error automatically.

3. Final Answer:

   The view will raise a 405 Method Not Allowed error -> Option B

4. Quick Check:

   @require_GET blocks POST with 405 error [OK]

Hint: require_GET blocks non-GET with 405 error [OK]

Common Mistakes:

• Assuming POST is accepted and returns normal response
• Thinking it crashes the server
• Believing it silently converts POST to GET

4. You have this Django view:

from django.views.decorators.http import require_POST
from django.http import HttpResponse

@require_POST
def submit_data(request):
    return HttpResponse('Data submitted')

When testing, you accidentally send a GET request and get an error. What is the most likely cause?

medium

A. The @require_POST decorator blocks GET requests causing a 405 error

B. The HttpResponse is not imported correctly

C. The view is missing a return statement

D. The view function name is invalid

Solution

1. Step 1: Analyze decorator effect on request methods

   The @require_POST decorator allows only POST requests and blocks others.

2. Step 2: Understand error cause on GET request

   Sending a GET request triggers a 405 Method Not Allowed error because GET is disallowed.

3. Final Answer:

   The @require_POST decorator blocks GET requests causing a 405 error -> Option A

4. Quick Check:

   @require_POST blocks GET with 405 error [OK]

Hint: GET requests fail on @require_POST with 405 error [OK]

Common Mistakes:

• Thinking missing return causes error
• Assuming HttpResponse import issue
• Blaming function name for HTTP method errors

5. You want a Django view to accept only POST requests but also want to add a custom message when a GET request is made instead of the default 405 error. Which approach correctly combines @require_POST with custom handling?

hard

A. Manually check request.method inside the view and return custom response without @require_POST

B. Use @require_POST and add a try-except block inside the view to catch MethodNotAllowed

C. Use @require_POST and catch the 405 error globally in middleware

D. Use @require_GET instead and handle POST requests manually

Solution

1. Step 1: Understand @require_POST behavior

   The @require_POST decorator returns an HttpResponseNotAllowed (405) directly without calling the view or raising an exception.

2. Step 2: Combine with custom handling

   To customize the 405 response while using the decorator, implement middleware that checks response.status_code == 405 in process_response and returns a custom message.

3. Final Answer:

   Use @require_POST and catch the 405 error globally in middleware -> Option C

4. Quick Check:

   @require_POST + middleware process_response for custom 405 [OK]

Hint: Middleware process_response customizes decorator's 405 response [OK]

Common Mistakes:

• Manually checking method without decorator (doesn't combine)
• Try-except in view (view not executed)
• Using @require_GET when POST is needed