Constant CORS 

pub const CORS: &str = r#"use rocket::fairing::{Fairing, Info, Kind};
use rocket::http::Header;
use rocket::{Request, Response};

pub struct Cors;

#[rocket::async_trait]
impl Fairing for Cors {
    fn info(&self) -> Info {
        Info {
            name: "Add cors headers to responses",
            kind: Kind::Response,
        }
    }

    async fn on_response<'r>(&self, _request: &'r Request<'_>, response: &mut Response<'r>) {
        response.set_header(Header::new("Access-Control-Allow-Origin", "*"));
        response.set_header(Header::new(
            "Access-Control-Allow-Methods",
            "POST, PATCH, PUT, DELETE, HEAD, OPTIONS, GET",
        ));
        response.set_header(Header::new("Access-Control-Allow-Headers", "*"));
        response.set_header(Header::new("Access-Control-Allow-Credentials", "true"));
    }
}
"#;