HTTP cheatsheet
HTTP: Methods and idempotency
6 common HTTP tasks.
GET: read a resource
Fetches data and must not change anything. It is safe and idempotent, so it can be cached and retried.
GET /users/42
POST: create or trigger something
Sends data to be processed, usually creating a resource. It is not idempotent: repeating it can create duplicates.
POST /users
PUT: replace a resource
Replaces the whole resource at a URL. It is idempotent: repeating it leaves the same result.
PUT /users/42
DELETE: remove a resource
Deletes the resource. It is idempotent: deleting twice leaves the same state.
DELETE /users/42
HEAD and OPTIONS
HEAD returns only the headers. OPTIONS asks what a server allows, and browsers use it for CORS preflight requests.
HEAD /users/42
OPTIONS /users