saraf-length-middelware.rs

use std::future::{ready, Ready};

use actix_web::{
    body::EitherBody,
    dev::{self, Service, ServiceRequest, ServiceResponse, Transform},
    web, Error, HttpResponse,
};
use futures_util::future::LocalBoxFuture;

use crate::{types::GenericResponse, utils::is_request_length_valid};

pub struct SarafLength;

impl<S: 'static, B> Transform<S, ServiceRequest> for SarafLength
where
    S: Service<ServiceRequest, Response = ServiceResponse<B>, Error = Error>,
    S::Future: 'static,
    B: 'static,
{
    type Response = ServiceResponse<EitherBody<B>>;
    type Error = Error;
    type InitError = ();
    type Transform = SarafLengthMiddleware<S>;
    type Future = Ready<Result<Self::Transform, Self::InitError>>;

    fn new_transform(&self, service: S) -> Self::Future {
        ready(Ok(SarafLengthMiddleware { service }))
    }
}
pub struct SarafLengthMiddleware<S> {
    service: S,
}

impl<S, B> Service<ServiceRequest> for SarafLengthMiddleware<S>
where
    S: Service<ServiceRequest, Response = ServiceResponse<B>, Error = Error> + 'static,
    S::Future: 'static,
    B: 'static,
{
    type Response = ServiceResponse<EitherBody<B>>;
    type Error = Error;
    type Future = LocalBoxFuture<'static, Result<Self::Response, Self::Error>>;

    dev::forward_ready!(service);

    fn call(&self, mut request: ServiceRequest) -> Self::Future {
        Box::pin(async move {
            let saraf_length = request.headers().get("saraf-length");

            if saraf_length.is_none() {
                let (request, _pl) = request.into_parts();

                let response = HttpResponse::Unauthorized()
                    .json(GenericResponse {
                        result: false,
                        message: "saraf-length header is missing".to_string(),
                    })
                    .map_into_right_body();

                return Ok(ServiceResponse::new(request, response));
            }

            let saraf_length: u32 = saraf_length.unwrap().to_str().unwrap().parse().unwrap();
            let body = request.extract::<web::Bytes>();

            // TODO: How to await here?
            if !is_request_length_valid(body.await.unwrap(), saraf_length) {
                let (request, _pl) = request.into_parts();

                let response = HttpResponse::Unauthorized()
                    .json(GenericResponse {
                        result: false,
                        message: "saraf-length header is missing".to_string(),
                    })
                    .map_into_right_body();

                return Ok(ServiceResponse::new(request, response));
            }

            let res = self.service.call(request);
            res.await.map(ServiceResponse::map_into_left_body)
        })
    }
}