RESTful HTTP Response Codes

Recently I have been building RESTful APIs in Ruby on Rails so I decided to compile a list of HTTP Status Codes to use. This is just a guideline.

Successful Responses:

• 200 (OK) – everything is fine
• 201 (Created)– resource successfully created
• 202 (Accepted) – the call returned but the request was queued up. Somewhat async behavior. Unclear how to communicate error, possibly through the resource state
• 204 (No Content) – A successful DELETE

Unsuccessful Responses:

• 400 (Bad Request) – the request could not be understood
• 401 (Unauthorized Access) – need to authenticate the client
• 404 (Not found) – the resource was not found, for requests like /resource/id
• 415 (Unsupported Media Type) – wrong content type in either “Content-Type” header or “Accept” header
• 422 (Un-processable Entity) – The request had right content type and the request was understood but the logic of the app prevented it from being complete
• 500 (Server Error) – something bad happened on the server, unexpected error