ASGI vs WSGI in Django - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the correct Django server interface for synchronous applications.

Django

from django.core.handlers.[1] import WSGIHandler

Drag options to blanks, or click blank then click option'

Async

Bwsgi

Chttp

Dasgi

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'asgi' instead of 'wsgi' for synchronous handler import.

Confusing the module name with 'http' or 'sync'.

The WSGIHandler is imported from django.core.handlers.wsgi for synchronous Django apps.

2fill in blank

medium

Complete the code to import the correct Django server interface for asynchronous applications.

Django

from django.core.handlers.[1] import ASGIHandler

Drag options to blanks, or click blank then click option'

Awsgi

Bhttp

Casync

Dasgi

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'wsgi' instead of 'asgi' for asynchronous handler import.

Confusing 'async' or 'http' as module names.

The ASGIHandler is imported from django.core.handlers.asgi for asynchronous Django apps.

3fill in blank

hard

Fix the error in the code to correctly create an ASGI application callable.

Django

application = [1]()

Drag options to blanks, or click blank then click option'

AASGIHandler

BDjangoHandler

CWSGIHandler

DHttpHandler

Attempts:

3 left

💡 Hint

Common Mistakes

Using WSGIHandler for ASGI application callable.

Using non-existent handler names.

For an ASGI app, the callable must be an instance of ASGIHandler.

4fill in blank

hard

Fill both blanks to complete the ASGI application setup with Django's async interface.

Django

import django

django.setup()
application = [1]()  # Create the [2] callable

Drag options to blanks, or click blank then click option'

AASGIHandler

BWSGIHandler

Csynchronous

Dasynchronous

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing ASGIHandler with 'synchronous' callable.

Using WSGIHandler for async callable.

ASGIHandler creates the asynchronous callable needed for async Django apps.

5fill in blank

hard

Fill all three blanks to create a dictionary mapping server interfaces to their Django handlers.

Django

handlers = {
    'wsgi': [1],
    'asgi': [2],
    'default': [3]
}

Drag options to blanks, or click blank then click option'

AWSGIHandler()

BASGIHandler()

CNone

DHttpHandler()

Attempts:

3 left

💡 Hint

Common Mistakes

Using handler classes without parentheses.

Assigning HttpHandler which does not exist.

Setting default to a handler instance instead of None.

The dictionary maps 'wsgi' to a WSGIHandler instance, 'asgi' to an ASGIHandler instance, and 'default' to None when no handler is set.

Practice

1. What is the main difference between WSGI and ASGI in Django?

easy

A. WSGI is faster than ASGI in all cases.

B. WSGI supports WebSocket, ASGI only supports HTTP.

C. WSGI is used for databases, ASGI is used for templates.

D. WSGI handles synchronous requests, ASGI supports asynchronous and real-time features.

Solution

1. Step 1: Understand WSGI's role

   WSGI is designed for synchronous web applications, handling one request at a time.

2. Step 2: Understand ASGI's role

   ASGI supports asynchronous code and real-time features like WebSocket, allowing multiple requests concurrently.

3. Final Answer:

   WSGI handles synchronous requests, ASGI supports asynchronous and real-time features. -> Option D

4. Quick Check:

   WSGI = synchronous, ASGI = asynchronous [OK]

Hint: Remember: ASGI = async and real-time support [OK]

Common Mistakes:

• Thinking WSGI supports WebSocket
• Confusing ASGI with database handling
• Assuming WSGI is always faster

2. Which of the following is the correct way to specify an ASGI application in Django's asgi.py file?

easy

A. application = get_wsgi_application()

B. application = get_application()

C. application = get_asgi_application()

D. application = asgi_application()

Solution

1. Step 1: Recall Django's ASGI setup

   Django provides get_asgi_application() to create the ASGI application instance.

2. Step 2: Compare options

   get_wsgi_application() is for WSGI, others are incorrect function names.

3. Final Answer:

   application = get_asgi_application() -> Option C

4. Quick Check:

   ASGI uses get_asgi_application() [OK]

Hint: ASGI uses get_asgi_application(), WSGI uses get_wsgi_application() [OK]

Common Mistakes:

• Using get_wsgi_application() in asgi.py
• Misspelling function names
• Confusing application variable names

3. Given this Django ASGI consumer code snippet, what will happen when a WebSocket connection is accepted?

from channels.generic.websocket import AsyncWebsocketConsumer

class ChatConsumer(AsyncWebsocketConsumer):
    async def connect(self):
        await self.accept()

medium

A. The server will crash due to missing HTTP response.

B. The WebSocket connection is accepted and ready to receive messages asynchronously.

C. The connection will be rejected because accept() is synchronous.

D. Nothing happens because connect() is not called automatically.

Solution

1. Step 1: Understand AsyncWebsocketConsumer behavior

   The connect method is called automatically on WebSocket connection attempts.

2. Step 2: Analyze the accept() call

   Calling await self.accept() accepts the WebSocket connection asynchronously, enabling message exchange.

3. Final Answer:

   The WebSocket connection is accepted and ready to receive messages asynchronously. -> Option B

4. Quick Check:

   Async accept() means connection accepted [OK]

Hint: Async accept() means WebSocket connection is accepted [OK]

Common Mistakes:

• Thinking accept() is synchronous
• Assuming connect() is not called automatically
• Confusing WebSocket with HTTP requests

4. You wrote this snippet in your Django asgi.py file but get an error:

from django.core.asgi import get_asgi_application

application = get_wsgi_application()

What is the problem?

medium

A. You imported get_asgi_application but called get_wsgi_application, causing a NameError.

B. You must import get_wsgi_application to use it.

C. The application variable name is incorrect.

D. There is no problem; this code works fine.

Solution

1. Step 1: Check imports and function calls

   The code imports get_asgi_application but calls get_wsgi_application(), which is not imported.

2. Step 2: Understand the error cause

   This mismatch causes a NameError because get_wsgi_application is undefined in this context.

3. Final Answer:

   You imported get_asgi_application but called get_wsgi_application, causing a NameError. -> Option A

4. Quick Check:

   Import and call must match [OK]

Hint: Import and function call must match exactly [OK]

Common Mistakes:

• Calling a function not imported
• Mixing ASGI and WSGI functions
• Assuming variable name causes error

5. You want to build a Django app that supports both HTTP requests and WebSocket connections for chat. Which setup should you choose and why?

hard

A. Use ASGI because it supports asynchronous HTTP and WebSocket connections.

B. Use WSGI because it handles HTTP and WebSocket natively.

C. Use WSGI with a separate WebSocket server.

D. Use ASGI but disable asynchronous features for compatibility.

Solution

1. Step 1: Identify requirements

   The app needs to handle HTTP requests and WebSocket connections for chat, which requires async support.

2. Step 2: Match server capabilities

   WSGI only supports synchronous HTTP, no WebSocket support. ASGI supports both async HTTP and WebSocket natively.

3. Step 3: Evaluate options

   Use ASGI because it supports asynchronous HTTP and WebSocket connections. correctly chooses ASGI for full async and WebSocket support in one server.

4. Final Answer:

   Use ASGI because it supports asynchronous HTTP and WebSocket connections. -> Option A

5. Quick Check:

   ASGI supports async HTTP + WebSocket [OK]

Hint: ASGI supports both HTTP and WebSocket asynchronously [OK]

Common Mistakes:

• Assuming WSGI supports WebSocket
• Using separate servers unnecessarily
• Disabling async features in ASGI