How fix CorsOptions for Rocket?

Question

I found this code for configuring CORS using rocket_cors:

use rocket::http::Method;
use rocket_cors::{AllowedOrigins, CorsOptions};

let cors = CorsOptions::default()
    .allowed_origins(AllowedOrigins::all())
    .allowed_methods(
        vec![Method::Get, Method::Post, Method::Patch]
            .into_iter()
            .map(From::from)
            .collect(),
    )
    .allow_credentials(true);

rocket::build().attach(cors.to_cors())

but when I run the program I get an error:

error[E0277]: the trait bound `rocket_cors::Method: From<rocket::http::Method>` is not satisfied
  --> src/main.rs:37:13
   |
37 | /             vec![Method::Get, Method::Post, Method::Patch]
38 | |                 .into_iter()
39 | |                 .map(From::from)
40 | |                 .collect(),
   | |__________________________^ the trait `From<rocket::http::Method>` is not implemented for `rocket_cors::Method`
   |
   = help: the trait `From<rocket_http::method::Method>` is implemented for `rocket_cors::Method`

I don't know how fix this.

Answer 1

The latest published stable versions of the crate (< 0.5.1) are not compatible with the latest versions of rustc and rocket.

You can use the development version of the crate using git + branch arguments in Cargo.toml.

Cargo.toml

[dependencies]
rocket_cors = { git = "https://github.com/lawliet89/rocket_cors", branch = "master" }
rocket = "0.5.0-rc.2"

Additionally the documentation state to use the manage-function instead of attach-function.

main.rs

#[macro_use] extern crate rocket;

use rocket::{Build, Rocket};
use rocket::http::Method;
use rocket_cors::{AllowedOrigins, CorsOptions};

#[launch]
fn rocket() -> Rocket<Build> {
    let cors = CorsOptions::default()
        .allowed_origins(AllowedOrigins::all())
        .allowed_methods(
            vec![Method::Get, Method::Post, Method::Patch]
                .into_iter()
                .map(From::from)
                .collect(),
        )
        .allow_credentials(true);
    rocket::build().manage(cors.to_cors())
}