How to handle REST Exceptions?

Question

We are in the middle of a ongoing discussion about how to handle REST exceptions.

Response Content type : JSON

Two solutions we have:

1. Throw all the unchecked exceptions as a JSON response.
2. Send Request Invalid Response code.

Arguments:

• When its a error, why return JSON? Just send a invalid response code.

Counter Argument:

• Response code are too technical to handle for normal developers.

Whats your say??

Answer 1

For a JSON API I recently developed I do both. I always respond with valid JSON (well, assuming I respond at all). If I detect an invalid request, I use status 400. If I detect a server error (which I don't believe is caused by an invalid request), I use a 5xx status. The JSON object contains a special key that is only set for errors, with a string value.

I think this is a good solution that respects REST principles, and can be used in multiple ways. The same solution is used by some other JSON APIs, such as Yahoo Search. Try http://search.yahooapis.com/ImageSearchService/V1/imageSearch?appid=YahooDemo&output=json .