HEAD and OPTIONS methods in Rest API - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this HEAD request?

Given a REST API endpoint that returns the following response for a GET request:

Status: 200 OK
Headers: Content-Type: application/json
Body: {"message": "Hello"}

What will be the response body when a HEAD request is made to the same endpoint?

A Body: empty

B Body: {"message": "Hello"}

C Body: null

D Body: "HEAD request not supported"

💡 Hint

Remember, HEAD requests return headers only, no body.

The HEAD method returns the same headers as GET but does not return a message body. So the body is empty.

❓ Predict Output

intermediate

What headers does an OPTIONS request return?

An OPTIONS request is sent to a REST API endpoint. Which header is expected in the response to indicate allowed methods?

A Cache-Control: no-cache

B Content-Type: application/json

C Allow: GET, POST, OPTIONS

D Authorization: Bearer token

💡 Hint

OPTIONS tells the client what methods are allowed on the resource.

The Allow header lists HTTP methods supported by the resource, returned in response to OPTIONS requests.

🧠 Conceptual

advanced

Why use HEAD instead of GET?

Which is the main reason to use the HEAD method instead of GET in REST APIs?

A To retrieve only headers without the response body, saving bandwidth

B To update a resource partially

C To delete a resource

D To create a new resource

💡 Hint

Think about checking resource metadata without downloading the content.

HEAD requests return headers only, useful to check metadata or existence without downloading the body.

❓ Predict Output

advanced

What error occurs if OPTIONS is not supported?

If a client sends an OPTIONS request to a REST API endpoint that does not support OPTIONS, what is the typical HTTP status code returned?

A 404 Not Found

B 405 Method Not Allowed

C 500 Internal Server Error

D 200 OK

💡 Hint

Think about what happens when a method is not allowed on a resource.

405 indicates the method is not allowed on the resource, which applies if OPTIONS is unsupported.

🧠 Conceptual

expert

How do HEAD and OPTIONS improve REST API efficiency?

Which statement best explains how HEAD and OPTIONS methods help improve REST API efficiency?

A HEAD creates new resources; OPTIONS modifies existing resources

B HEAD caches responses automatically; OPTIONS encrypts data for security

C HEAD updates resource metadata; OPTIONS deletes unused resources

D HEAD reduces data transfer by sending headers only; OPTIONS informs clients of allowed methods without extra requests

💡 Hint

Consider how these methods reduce unnecessary data and requests.

HEAD avoids sending body data when only headers are needed; OPTIONS lets clients know allowed methods to avoid trial-and-error requests.