Why this error trying to conditionally wrap my actix-web app?

[frederikhors]

I'm trying to conditionally wrap my app with CORS, but I'm getting errors.

use actix_cors::Cors;
use actix_web::{http::header, App, HttpServer};
use std::{net::SocketAddr, sync::Arc};

use common::config::Config;

pub async fn start(config: Arc<Config>) -> std::io::Result<()> {
    let config_app = Arc::clone(&config);

    let server = HttpServer::new(move || {
        let mut app = App::new();

        if config_app.cors.enabled {
            app = app.wrap( // the error is here, read below
                Cors::default()
                    .allowed_origin("http://localhost:8080")
                    .allowed_methods(vec!["GET", "POST"])
                    .allowed_headers(vec![header::AUTHORIZATION, header::ACCEPT])
                    .allowed_header(header::CONTENT_TYPE)
                    .supports_credentials()
                    .max_age(3600),
            )
        }

        app
    });

    let addr = SocketAddr::from(([127, 0, 0, 1], config.port));

    server.bind(addr)?.run().await
}

the error is:

mismatched types
expected struct `actix_web::App<actix_web::app_service::AppEntry>`
   found struct `actix_web::App<impl actix_web::dev::ServiceFactory<actix_web::dev::ServiceRequest, Config = (), Response = actix_web::dev::ServiceResponse<actix_web::body::EitherBody<actix_web::body::BoxBody>>, Error = actix_web::Error, InitError = ()>>` rustc E0308

app.rs(355, 9): the found opaque type

server.rs(13, 23): expected due to this value

Why?

[asonix]

by applying .wrap to an App you change it's type

[frederikhors]

Thanks. Can you suggest a way to do this?

[asonix]

https://docs.rs/actix-web-extras/latest/actix_web_extras/middleware/struct.Condition.html

[robjtede]

Is there a reason to use this third party Condition middleware over the built-in one?

[asonix]

oops! I guess I missed that