If you are reading this blog then you must have come across the OPTIONS request in an API call, but what exactly is an Options Method

well if you make a server request from the front end to the backend, and log the requests made to the server by using a logging package (in the Context of Nodejs) you will get a result like this.

OPTIONS /api/users/signup 204 2.247 ms - 0
POST /api/users/signup 201 519.913 ms - 333

in this example, we are signing up the user, and the endpoint is

/api/users/signup

Now we know what a POST method is but what is this OPTIONS method?

Let's break this down,

HTTP Method: OPTIONS

Endpoint: /api/users/signup

Status Code: 204

Response Time: 2.247 ms

Response Size: - 0 (indicating a response with no content)

To put it in simple words an OPTIONS request is a part of the CORS (Cross-Origin Resource Sharing) mechanism.

The OPTIONS method is often used to request information about the communication options available for a target resource, including the permitted HTTP methods or the supported headers. It's part of the HTTP/1.1 protocol, and browsers often send OPTIONS requests as a pre-flight check before making a cross-origin request (e.g., for a POST request with certain headers).

in our current example :

The client, typically a web browser, is checking what methods are allowed on the /api/users/signup endpoint and what headers can be used in the actual request.

Status Code (204): This status code indicates that the server successfully processed the OPTIONS request, and there is no additional information to send in the response payload. thus the response is empty, as indicated by - 0.

In a nutshell:

Browsers often perform this pre-flight request to determine if the actual request (e.g., a POST request) will be allowed by the server. The server responds with information about the allowed methods, headers, and other details.
Thus HTTP OPTIONS request method is useful for determining what commands are available for use on a target server or for a specific resource.