Include request body in response

src/main.rs

@@ -1,5 +1,10 @@
-use actix_web::{App, HttpRequest, HttpResponse, HttpServer, Responder, web};
+use actix_web::{App, Error, error, HttpRequest, HttpResponse, HttpServer, web};
+use actix_web::web::Payload;
 use clap::Parser;
+use futures::StreamExt;
+
+const MAX_BODY_SIZE: usize = 262_144; // max payload size is 256k
+
 
 /// Simple HTTP responder
 #[derive(Parser, Debug)]
@@ -10,24 +15,36 @@ struct Args {
     listen_address: String,
 }
 
-async fn handler(req: HttpRequest) -> impl Responder {
+async fn handler(req: HttpRequest, mut payload: Payload) -> Result<HttpResponse, Error> {
     let mut headers = req.headers().iter()
         .map(|h| format!("{}: {}", h.0.as_str(), h.1.to_str().unwrap_or_default()))
         .collect::<Vec<_>>();
     headers.sort();
 
-    let body = format!(
-        "Remote Peer: {}\nVerb: {}\nPath: {}\nQuery: {}\n\n=== Headers ===\n{}",
+    let mut body = web::BytesMut::new();
+    while let Some(chunk) = payload.next().await {
+        let chunk = chunk?;
+        // limit max size of in-memory payload
+        if (body.len() + chunk.len()) > MAX_BODY_SIZE {
+            return Err(error::ErrorBadRequest("overflow"));
+        }
+        body.extend_from_slice(&chunk);
+    }
+
+
+    let response = format!(
+        "Remote Peer: {}\nVerb: {}\nPath: {}\nQuery: {}\n\n=== Headers ===\n{}\n\n=== Body ===\n{}",
         req.peer_addr().expect("Missing remote peer address!"),
         req.head().method,
         req.uri().path(),
         req.uri().query().unwrap_or_default(),
-        headers.join("\n")
+        headers.join("\n"),
+        String::from_utf8_lossy(&body)
     );
 
-    HttpResponse::Ok()
+    Ok(HttpResponse::Ok()
         .content_type("text/plain")
-        .body(body)
+        .body(response))
 }
 
 #[actix_web::main]