WebSocket endpoint creation in FastAPI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the WebSocket class from FastAPI.

FastAPI

from fastapi import [1]

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

AWebSocket

BRequest

CDepends

DHTTPException

Attempts:

3 left

💡 Hint

Common Mistakes

Importing unrelated classes like Request or Depends.

Forgetting to import WebSocket causes errors when defining the endpoint.

The WebSocket class is imported from FastAPI to create WebSocket endpoints.

2fill in blank

medium

Complete the code to define a WebSocket endpoint path '/ws'.

FastAPI

@app.websocket("[1]")
def websocket_endpoint(websocket: WebSocket):
    await websocket.accept()

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

A/socket

B/ws

C/websocket

D/chat

Attempts:

3 left

💡 Hint

Common Mistakes

Using HTTP route decorators like @app.get instead of @app.websocket.

Missing the leading slash in the path string.

The WebSocket endpoint is defined at path /ws using the @app.websocket decorator.

3fill in blank

hard

Fix the error in the code to accept the WebSocket connection properly.

FastAPI

async def websocket_endpoint(websocket: WebSocket):
    await websocket.[1]()

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

Aconnect

Bstart

Caccept

Dopen

Attempts:

3 left

💡 Hint

Common Mistakes

Using non-existent methods like connect() or open() causes runtime errors.

Forgetting to accept the connection leads to client connection failures.

The method accept() is used to accept an incoming WebSocket connection.

4fill in blank

hard

Fill both blanks to receive a text message and send it back to the client.

FastAPI

data = await websocket.[1]()
await websocket.[2](data)

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

Areceive_text

Bsend_text

Creceive_bytes

Dsend_bytes

Attempts:

3 left

💡 Hint

Common Mistakes

Using receive_bytes() when expecting text causes type errors.

Sending bytes when client expects text causes message format errors.

Use receive_text() to get a text message and send_text() to send it back.

5fill in blank

hard

Fill all three blanks to create a complete WebSocket echo endpoint that accepts, receives, sends, and closes the connection.

FastAPI

from fastapi import FastAPI, WebSocket

app = FastAPI()

@app.websocket("/echo")
async def echo_endpoint(websocket: WebSocket):
    await websocket.[1]()
    data = await websocket.[2]()
    await websocket.[3](data)
    await websocket.close()

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

Aaccept

Breceive_text

Csend_text

Dconnect

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'connect' instead of 'accept' causes errors.

Mixing receive_text with send_bytes or vice versa causes message format issues.

This code accepts the WebSocket connection, receives a text message, sends it back, and then closes the connection.