Valid JSON in Response

Question

I am working on a client and server application and came across an interesting problem. We are creating a restful API and communicating to the clients with JSON responses. When doing a DELETE, we are returning a 200 OK with a blank response. Our clients are getting the 200 OK, but failing on parsing the JSON.

We completely understand the failed parse (there is nothing to parse), but we had a bigger question. Is sending a blank response valid JSON, or should we be returning {} or something to that effect? Thanks.

Answer 1

From the HTTP/1.1 definition concerning the DELETE method:

A successful response SHOULD be 200 (OK) if the response includes an entity describing the status, 202 (Accepted) if the action has not yet been enacted, or 204 (No Content) if the action has been enacted but the response does not include an entity.

So if your server is deleting the item immediately, then the suggested responses would be:

• 200 OK - return some kind of status code (like a boolean true, or a string saying "success")
• 204 No Content - return nothing, and have your client look out for this response and not attempt JSON parsing, while still knowing the request was successful

Answer 2

Just doing a quick test here: http://jsonlint.com/ reveals that a blank is not valid JSON, while {} is valid JSON.