http-signature-normalization/http-signature-normalization-reqwest/src/digest/mod.rs

use reqwest::Request;
use std::{future::Future, pin::Pin};

pub trait CreateDigest {
    fn create_digest(&mut self, payload: &[u8]) -> String;
}

pub trait WithDigest: Sized {
    type Future: Future<Output = Self>;

    fn with_digest<T>(&mut self, creator: T) -> Self::Future;
}

impl WithDigest for Request {
    type Future = Pin<Box<dyn Future<Output = Self> + Send>>;
}