200 OK and 201 Created in Rest API - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the HTTP status code returned for a successful GET request?

Consider a REST API where a client sends a GET request to retrieve data. Which HTTP status code should the server return to indicate success?

A 200 OK

B 201 Created

C 404 Not Found

D 500 Internal Server Error

💡 Hint

Think about the difference between retrieving existing data and creating new data.

200 OK is the standard response for successful GET requests where data is retrieved without creating anything new.

❓ Predict Output

intermediate

What status code is returned after successfully creating a new resource?

When a client sends a POST request to create a new resource, which HTTP status code should the server return to indicate the resource was created successfully?

A 204 No Content

B 200 OK

C 201 Created

D 400 Bad Request

💡 Hint

This status code means something new was made.

201 Created means the server successfully created a new resource in response to the POST request.

🧠 Conceptual

advanced

Why should a POST request return 201 Created instead of 200 OK?

Explain why it is better REST practice for a POST request that creates a resource to return 201 Created rather than 200 OK.

A 201 Created explicitly indicates a new resource was created, while 200 OK only means the request succeeded without specifying creation.

B 201 Created is used only when the resource is created on the client side, not the server side.

C 201 Created means the server will send the resource again in the response body, 200 OK does not.

D 200 OK is only for GET requests and cannot be used for POST requests.

💡 Hint

Think about the meaning of each status code and what information it conveys to the client.

201 Created clearly tells the client that a new resource was made, which is more informative than the generic 200 OK.

❓ Predict Output

advanced

What is the response status code and body after a successful POST creating a resource with location header?

A client sends a POST request to create a new user. The server creates the user and returns a response with a Location header pointing to the new user URL. What is the expected status code and typical response body?

A Status: 404 Not Found, Body: Error message

B Status: 200 OK, Body: Empty

C Status: 204 No Content, Body: Empty

D Status: 201 Created, Body: JSON with new user details

💡 Hint

Think about what 201 Created means and what the Location header is for.

201 Created with a Location header and a body containing the new resource details is the standard RESTful response after creating a resource.

🧠 Conceptual

expert

How should a REST API handle a POST request that creates a resource but the client sends duplicate data?

A client sends a POST request to create a resource, but the resource already exists with the same data. What is the best RESTful status code and response behavior?

A Return 404 Not Found because the resource cannot be created again.

B Return 409 Conflict with an error message explaining the duplicate resource.

C Return 200 OK with no body to silently ignore the duplicate.

D Return 201 Created again with the existing resource data.

💡 Hint

Think about how to inform the client that the resource already exists and cannot be duplicated.

409 Conflict is the correct status to indicate the request conflicts with the current state of the server, such as duplicate resource creation.