HTTP Reference Tables

Status codes, request methods and common header fields.

Request methods

MethodSafeIdempotentBodyNotes
GETyesyesnoTransfer a current representation of the target resource.
HEADyesyesnoSame as GET but without a response body.
POSTnonoyesPerform resource specific processing on the payload.
PUTnoyesyesReplace the target resource with the payload.
PATCHnonoyesApply a partial modification to the resource.
DELETEnoyesoptionalRemove the association between target and function.
OPTIONSyesyesoptionalDescribe the communication options for the target.
TRACEyesyesnoPerform a loop back test along the path to the target.

Conditional requests

A conditional request carries a precondition header such as If-Match or If-None-Match. When the precondition fails the server answers 412 Precondition Failed, or 304 Not Modified for a successful cache validation.