Why middleware processes requests globally in FastAPI - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a middleware function in FastAPI.

FastAPI

from fastapi import FastAPI
app = FastAPI()

@app.middleware("[1]")
async def log_requests(request, call_next):
    response = await call_next(request)
    return response

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

Arequest

Bhttp

Cmiddleware

Droute

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'request' or 'route' instead of 'http' in the decorator.

Forgetting to make the middleware function async.

The middleware decorator in FastAPI uses the string "http" to indicate it processes HTTP requests globally.

2fill in blank

medium

Complete the code to call the next middleware or route handler inside the middleware.

FastAPI

async def log_requests(request, call_next):
    response = await [1](request)
    return response

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

Arequest

Bhandle_request

Cnext_call

Dcall_next

Attempts:

3 left

💡 Hint

Common Mistakes

Calling 'request' or other variables instead of 'call_next'.

Not using await before call_next.

Inside middleware, you call the next handler using the 'call_next' function with the request.

3fill in blank

hard

Fix the error in the middleware function to ensure it processes all requests globally.

FastAPI

from fastapi import FastAPI
app = FastAPI()

@app.middleware("http")
async def [1](request, call_next):
    response = await call_next(request)
    return response

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

Alog_requests

Bprocess_request

Chandle_request

Dmiddleware_func

Attempts:

3 left

💡 Hint

Common Mistakes

Using generic or unclear function names.

Using reserved keywords as function names.

The middleware function name can be anything, but 'log_requests' is the conventional name used here to indicate its purpose.

4fill in blank

hard

Fill both blanks to create a middleware that adds a custom header to every response.

FastAPI

from fastapi import FastAPI
app = FastAPI()

@app.middleware("http")
async def add_header(request, call_next):
    response = await call_next(request)
    response.headers[[1]] = [2]
    return response

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

A"X-Custom-Header"

B"Content-Type"

C"Hello"

D"application/json"

Attempts:

3 left

💡 Hint

Common Mistakes

Using standard headers like 'Content-Type' instead of a custom one.

Not using quotes around header names and values.

The middleware adds a custom header named "X-Custom-Header" with the value "Hello" to every response.

5fill in blank

hard

Fill both blanks to create a middleware that logs the request method and path before processing.

FastAPI

from fastapi import FastAPI
app = FastAPI()

@app.middleware("http")
async def log_request_info(request, call_next):
    print(f"Request: [1] [2]")
    response = await call_next(request)
    return response

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

Arequest.method

Brequest.url.path

Crequest.headers

Drequest.body

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'request.headers' or 'request.body' instead of method and path for logging.

Not using f-string formatting correctly.

The middleware prints the HTTP method and URL path of the incoming request before calling the next handler.