rocket_cors/src/fairing.rs

108 lines
3.6 KiB
Rust

//! Fairing implementation
use rocket::{self, Request, Outcome};
use rocket::http::{self, Status};
use {Cors, Error, validate, preflight_response, actual_request_response, origin, request_headers};
/// Route for Fairing error handling
pub(crate) fn fairing_error_route<'r>(
request: &'r Request,
_: rocket::Data,
) -> rocket::handler::Outcome<'r> {
let status = request.get_param::<u16>(0).unwrap_or_else(|e| {
error_!("Fairing Error Handling Route error: {:?}", e);
500
});
let status = Status::from_code(status).unwrap_or_else(|| Status::InternalServerError);
Outcome::Failure(status)
}
/// Create a new `Route` for Fairing handling
fn fairing_route() -> rocket::Route {
rocket::Route::new(http::Method::Get, "/<status>", fairing_error_route)
}
/// Modifies a `Request` to route to Fairing error handler
fn route_to_fairing_error_handler(options: &Cors, status: u16, request: &mut Request) {
request.set_method(http::Method::Get);
request.set_uri(format!("{}/{}", options.fairing_route_base, status));
}
fn on_response_wrapper(
options: &Cors,
request: &Request,
response: &mut rocket::Response,
) -> Result<(), Error> {
let origin = match origin(request)? {
None => {
// Not a CORS request
return Ok(());
}
Some(origin) => origin,
};
let cors_response = if request.method() == http::Method::Options {
let headers = request_headers(request)?;
preflight_response(options, origin, headers)
} else {
actual_request_response(options, origin)
};
cors_response.merge(response);
// If this was an OPTIONS request and no route can be found, we should turn this
// into a HTTP 204 with no content body.
// This allows the user to not have to specify an OPTIONS route for everything.
//
// TODO: Is there anyway we can make this smarter? Only modify status codes for
// requests where an actual route exist?
if request.method() == http::Method::Options && request.method() == http::Method::Options &&
request.route().is_none()
{
response.set_status(Status::NoContent);
let _ = response.take_body();
}
Ok(())
}
impl rocket::fairing::Fairing for Cors {
fn info(&self) -> rocket::fairing::Info {
rocket::fairing::Info {
name: "CORS",
kind: rocket::fairing::Kind::Attach | rocket::fairing::Kind::Request |
rocket::fairing::Kind::Response,
}
}
fn on_attach(&self, rocket: rocket::Rocket) -> Result<rocket::Rocket, rocket::Rocket> {
match self.validate() {
Ok(()) => {
Ok(rocket.mount(&self.fairing_route_base, vec![fairing_route()]))
}
Err(e) => {
error_!("Error attaching CORS fairing: {}", e);
Err(rocket)
}
}
}
fn on_request(&self, request: &mut Request, _: &rocket::Data) {
// Build and merge CORS response
// Type annotation is for sanity check
let cors_response = validate(self, request);
if let Err(ref err) = cors_response {
error_!("CORS Error: {}", err);
let status = err.status();
route_to_fairing_error_handler(self, status.code, request);
}
}
fn on_response(&self, request: &Request, response: &mut rocket::Response) {
if let Err(err) = on_response_wrapper(self, request, response) {
error_!("Fairings on_response error: {}\nMost likely a bug", err);
response.set_status(Status::InternalServerError);
let _ = response.take_body();
}
}
}