HTTP status code for update and delete?
RFC 2616 describes which status codes to use.
And no, it's not always 200.
For a PUT request: HTTP 200, HTTP 204 should imply "resource updated successfully". HTTP 201 if the PUT request created a new resource.
For a DELETE request: HTTP 200 or HTTP 204 should imply "resource deleted successfully".
HTTP 202 can also be returned by either operation and would imply that the instruction was accepted by the server, but not fully applied yet. It's possible that the operation fails later, so the client shouldn't fully assume that it was success.
A client that receives a status code it doesn't recognize, but it's starting with 2 should treat it as a 200 OK.
PUT
If an existing resource is modified, either the 200 (OK) or 204 (No Content) response codes SHOULD be sent to indicate successful completion of the request.
DELETE
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.
Source: W3.org: HTTP/1.1 Method Definitions
HTTP 200 OK: Standard response for successful HTTP requests. The actual response will depend on the request method used.
HTTP 204 No Content: The server successfully processed the request, but is not returning any content
Source: List of HTTP status codes: 2xx Success
Here are some Tips:
DELETE
200 (if you want send some additional data in the Response) or 204 (recommended).
202 Operation deleted has not been committed yet.
If there's nothing to delete, use 204 or 404 (DELETE operation is idempotent, delete an already deleted item is operation successful, so you can return 204, but it's true that idempotent doesn't necessarily imply the same response)
Other errors:
- 400 Bad Request (Malformed syntax or a bad query is strange but possible).
- 401 Unauthorized Authentication failure
- 403 Forbidden: Authorization failure or invalid Application ID.
- 405 Not Allowed. Sure.
- 409 Resource Conflict can be possible in complex systems.
- And 501, 502 in case of errors.
PUT
If you're updating an element of a collection
- 200/204 with the same reasons as DELETE above.
- 202 if the operation has not been commited yet.
The referenced element doesn't exists:
PUT can be 201 (if you created the element because that is your behaviour)
404 If you don't want to create elements via PUT.
400 Bad Request (Malformed syntax or a bad query more common than in case of DELETE).
401 Unauthorized
403 Forbidden: Authentication failure or invalid Application ID.
405 Not Allowed. Sure.
409 Resource Conflict can be possible in complex systems, as in DELETE.
422 Unprocessable entity It helps to distinguish between a "Bad request" (e.g. malformed XML/JSON) and invalid field values
And 501, 502 in case of errors.
Short answer: for both PUT and DELETE, you should send either 200 (OK) or 204 (No Content).
Long answer: here's a complete decision diagram (click to magnify).
Source: https://github.com/for-GET/http-decision-diagram