🔗 HTTP / HTTP Messages
HTTP defines a set of request methods to indicate the desired action to be performed for a given resource. Although they can also be nouns, these request methods are sometimes referred to as HTTP verbs. Each of them implements a different semantic, but some common features are shared by a group of them: e.g. a request method can be safe, idempotent, or cacheable.
Safe
An HTTP method is safe if it doesn’t alter the state of the server. In other words, a method is safe if it leads to a read-only operation. Several common HTTP methods are safe: GET, HEAD, or OPTIONS. All safe methods are also idempotent, but not all idempotent methods are safe. For example, PUT and DELETE are both idempotent but unsafe.
Idempotent
An HTTP method is idempotent if the intended effect on the server of making a single request is the same as the effect of making several identical requests.
This does not necessarily mean that the request does not have any unique side effects: for example, the server may log every request with the time it was received. Idempotency only applies to effects intended by the client: for example, a POST request intends to send data to the server, or a DELETE request intends to delete a resource on the server.
Cacheable
A cacheable response is an HTTP response that can be cached, that is stored to be retrieved and used later, saving a new request to the server. Not all HTTP responses can be cached.
| Method | Description |
|---|---|
GET | The GET method requests a representation of the specified resource. Requests using GETshould only retrieve data. |
HEAD | The HEAD method asks for a response identical to a GET request, but without the response body. |
POST | The POST method submits an entity to the specified resource, often causing a change in state or side effects on the server. |
PUT | The PUT method replaces all current representations of the target resource with the request payload. |
DELETE | The DELETE method deletes the specified resource. |
CONNECT | The CONNECT method establishes a tunnel to the server identified by the target resource. |
OPTIONS | The OPTIONS method describes the communication options for the target resource. |
TRACE | The TRACE method performs a message loop-back test along the path to the target resource. |
PATCH | The PATCH method applies partial modifications to a resource. |
References
📂 HTTP | Последнее изменение: 20.02.2024 16:51