How can we set cookies with spring boot?

We are assuming that you already know about HTTP Cookies and how they can be sent using plain JAVA or any other programming language.

In spring boot we do have a controller and HTTP handler. Controller declares several handlers to handle HTTP requests at different paths and HTTP methods. Cookies can be set from the HTTP handler in spring boot. Here is an simple architecture of how it works. 

Here is how we can set cookies in spring boot...

      @GetMapping("/auth")
public ResponseEntity < String > auth(HttpServletResponse response) {
    HttpCookie cookie = new HttpCookie("token", "xxx");
    return ResponseEntity
        .status(HttpStatus.OK)
        .header(
            HttpHeaders.SET_COOKIE,
            cookie.toString()
        )
        .body("Authentication success!");
}
    

We are using the HttpCookie class to build a key/value pair of cookies. We can also add path, secure etc to the cookie

In the end, we send the cookie as a string in the http header which will be interpreted by the browser. The browser will then store cookies which will be sent in further HTTP requests.