RESTFUL API

Class: API

is a network interface design style used for interaction between network applications. Verb + Object
- GET: Read
- POST: Create
- PUT: Update
- DELETE: Delete

NB:

according to HTTP specifications verbs should be always in UPPERCASE.
The object must be a noun. The URL usually represents a resource that serves as object of HTTP verb. URL should be a noun rather than a verb cuz they represent a resource collection or a single instance rather than an action.
INCORRECT CORRECT /GetAllCars /users →collection of cars /CreateNewCar /users/123 →instance of users
When your URL points to a collection of resources, use plural nouns (users), even when pointing to a single user using a plural noun is good. e.g.: users/123

GET: 200 OK - request was successful & the resource has returned
POST: 201 Created - new resource was successfully created
PUT: 200 OK / 204: No Content - used for full resource updates. If content is returned use 200 if not use 204.
PATCH: 200 OK / 204 No Content- used for partial updates similar to PUT, 204 indicates no content returned.
DELETE: 204 No Content - indicates the content was successfully deleted usually with no content in the response.
202 ACCEPETED - request has been accepted but not yet processed, useful for asynchronous operations.
206 Partial Content - Indicates a partial response.

API’s typically don’t allow 301(permanent redirect) or 302(temporary redirect) including 307, since they are mostly relevant for browser-level-navigation.
But, API’s may use 303 see other which references another URL like 302 & 307 it means temporary re-direct but 303 is specifically for POST, PUT & DELETE requests, unlike 302 browser don’t follow automatically 303 request but instead allow the user to decide the next step.

400 Bad Request - The server doesn’t understand the clients request and doesn’t process it.
401 Unauthorized - user doesn’t provide authentication credentials or failed authentication
403 Forbidden - authenticates successfully but lacks permission to access the response
404 Not Found - the requested response doesn’t exist
405 Method Not Allowed - authenticates successfully but uses HTTP method that’s not allowed
410 Gone - the requested resource has been permanently removed
415 Unsupported Media type - requested format that is not supported
422 unprocessed entity - the client provided an attachment that is not supported
429 Too Many Requests - the client has exceeded the allowed number of requests.

API’s don’t usually expose internal server details to users, so only two status codes are typically used
500 Internal Server Error - the client’s request was valid but the server encounters an issue while processing it.
503 Service unavailable - the server is temporarily unable to accept requests, often used for maintenance periods.