Is REST DELETE really idempotent?

Question

DELETE is supposed to be idempotent.

If I DELETE http://example.com/account/123 it\'s going to delete the account.

If I do it again would I expect a 404, sin

Answer 1

The important distinction is that idempotent refers to side-effects, not all-effects or responses. If you do a DELETE http://example.com/account/123 then the effect is that account 123 is now deleted from the server. That is the one and only effect, the one and only change to the state of the server. Now lets say you do the same DELETE http://example.com/account/123 request again, the server will respond differently, but its state is the same.

Its not like the DELETE request decided to change the server state in a different way because the account was missing, such as removing another account, or leaving an error log. Nay, you could call the same DELETE request a million times and you can be sure that the server is in the same state as it was the first time you called it.