Which header would you inspect to determine the client’s preferred response format, such as JSON?

Which header would you inspect to determine the client’s preferred response format, such as JSON?

• A. Content-Type
• B. Accept
• C. Server
• D. User-Agent

Answer: (B)

Clients tell servers what response formats they can handle with the Accept header. This is how content negotiation decides whether the server should return JSON, XML, HTML, or another representation. If the client wants JSON, it sends Accept: application/json, and the server should respond with a representation in JSON if possible. The server may choose the best match or return a 406 Not Acceptable if none of the offered formats are available. The Content-Type header, on the other hand, indicates the actual format of the data in the message body (what is sent or what is returned), not the client’s stated preferences. The other headers identify who is making the request or details about the server, not the requested format. So inspecting the Accept header reveals the client’s preferred response format, such as JSON.

Clients tell servers what response formats they can handle with the Accept header. This is how content negotiation decides whether the server should return JSON, XML, HTML, or another representation. If the client wants JSON, it sends Accept: application/json, and the server should respond with a representation in JSON if possible. The server may choose the best match or return a 406 Not Acceptable if none of the offered formats are available. The Content-Type header, on the other hand, indicates the actual format of the data in the message body (what is sent or what is returned), not the client’s stated preferences. The other headers identify who is making the request or details about the server, not the requested format. So inspecting the Accept header reveals the client’s preferred response format, such as JSON.