Idempotency keys for safe retries in Rest API - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to add an idempotency key header to the API request.

Rest API

headers = {"Content-Type": "application/json", "[1]": "12345-abcde"}

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

AAccept

BAuthorization

CIdempotency-Key

DUser-Agent

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Authorization' instead of 'Idempotency-Key'.

Forgetting to add the idempotency key header.

The Idempotency-Key header is used to safely retry requests without creating duplicates.

2fill in blank

medium

Complete the code to check if the idempotency key already exists in the server's storage.

Rest API

if [1] in stored_keys:
    return stored_keys[[1]]

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

Arequest.body

Brequest.headers.get('Idempotency-Key')

Crequest.method

Drequest.url

Attempts:

3 left

💡 Hint

Common Mistakes

Checking the request body instead of headers.

Using the URL or method instead of the idempotency key.

We check if the Idempotency-Key from the request headers is already stored to avoid duplicate processing.

3fill in blank

hard

Fix the error in the code that stores the response using the idempotency key.

Rest API

stored_keys[[1]] = response

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Arequest.headers.get('Idempotency-Key')

Brequest.body

Cresponse.status_code

Drequest.url

Attempts:

3 left

💡 Hint

Common Mistakes

Using request body or URL as the key instead of the idempotency key.

Storing the status code instead of the full response.

The response must be stored with the Idempotency-Key from the request headers as the key.

4fill in blank

hard

Fill both blanks to safely retry a POST request using idempotency key logic.

Rest API

key = request.headers.get('[1]')
if key and key [2] stored_keys:
    return stored_keys[key]

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

AIdempotency-Key

Bnot in

Cin

DAuthorization

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'not in' instead of 'in' for the check.

Using wrong header names like 'Authorization'.

The code gets the Idempotency-Key from headers and checks if it is in stored keys to return the saved response.

5fill in blank

hard

Fill all three blanks to implement idempotency key storage and response retrieval.

Rest API

key = request.headers.get('[1]')
if key [2] stored_keys:
    return stored_keys[key]
response = process_request(request)
stored_keys[[3]] = response

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

AIdempotency-Key

Bin

Ckey

DAuthorization

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Authorization' instead of 'Idempotency-Key'.

Using 'not in' instead of 'in' for the check.

Storing response with wrong dictionary key.

The code gets the Idempotency-Key, checks if it is in stored keys, returns the stored response if found, otherwise processes the request and stores the response with the key.