The POST method in a REST API is used to create a new resource on the server. It is typically used when a client wants to send data to the server to create a new resource or update an existing one.
The POST method is not idempotent, meaning that making multiple identical requests will not have the same effect as making a single request, and it may result in creating multiple resources.
A typical POST request will include the following:
The HTTP verb “POST”
- The endpoint or resource location, such as “/products”
- The headers, which may include additional information such as the content type or the authentication information
- The request body, which contains the data that the client wants to send to the server in order to create the new resource.
A typical POST response will include the following:
- The HTTP status code, such as 201 Created if the request was successful or 400 Bad Request if the request was malformed or invalid.
- The headers, which may include additional information such as the location of the new resource or the content type.
- The response body, which may contain the newly created resource or additional information about the status of the request.
It’s worth noting that the POST method is typically used to send data to the server to create a new resource, but it could also be used to update an existing one, depending on the API’s design.
Additionally, the POST method is not idempotent, which means that making multiple identical requests will not have the same effect as making a single request, and it may result in creating multiple resources.
Also, it’s a common practice to use the POST method to submit forms, as it allows sending data to the server that should not be cached or saved in browser’s history.