How to read a request body in an actix-web 4.0 middleware?

[JiabinTang]

use std::time::Instant;
use actix_service::forward_ready;
use actix_web::dev::{Service, ServiceRequest, ServiceResponse, Transform};
use actix_web::{Error};
use actix_web::http::header::HeaderMap;
use futures::future::{ok, LocalBoxFuture, Ready};
use log::info;
use chrono::Local;
use serde_json::json;

pub struct Logging;

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

    fn new_transform(&self, service: S) -> Self::Future {
        ok(LoggingMiddleware { service })
    }
}

pub struct LoggingMiddleware<S> {
    service: S,
}

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

    forward_ready!(service);

    fn call(&self, req: ServiceRequest) -> Self::Future {
        let method = req.method().clone();
        let path = req.path().to_string();
        let query_string = req.query_string().to_string();
        let headers = req.headers().clone();
        let headers_json = headers_to_json(&headers);
        let client_ip = req.peer_addr().map(|addr| addr.ip().to_string()).unwrap_or_default();
        let start_instant = Instant::now();
        let start_time_str = Local::now().format("%Y-%m-%d %H:%M:%S").to_string();

        info!("================================  网关请求响应日志  ===============================");
        info!("请求路径: {}", path);
        info!("请求方法: {}", method);
        info!("查询参数: {}", query_string);
        info!("请求头部: {}", headers_json);
        info!("请求时间: {}", start_time_str);
        info!("请求 IP: {}", client_ip);
        // info!("请求数据: {:?}", req.body());
        // how to get request body

        let fut = self.service.call(req);

        Box::pin(async move {

            let res = fut.await?;
            let duration = start_instant.elapsed();
            let end_time_str = Local::now().format("%Y-%m-%d %H:%M:%S").to_string();

            // how to get response body
            // info!("响应数据: {:?}", res.response().body());
            info!("响应时间: {}", end_time_str);
            info!("执行耗时: {} 毫秒", duration.as_millis());
            info!("==================================================================================");

            Ok(res)
        })
    }
}

fn headers_to_json(headers: &HeaderMap) -> serde_json::Value {
    let mut map = serde_json::Map::new();
    for (key, value) in headers.iter() {
        let values: Vec<String> = value.to_str().unwrap_or("").split(',').map(|s| s.trim().to_string()).collect();
        map.insert(key.to_string(), json!(values));
    }
    json!(map)
}

[robjtede]

see examples: https://github.com/actix/examples/blob/1d55c08a7e0290610789aedf7b6bf1b17060ec66/middleware/various/src/read_request_body.rs#L54-L60