1 files changed, 59 insertions, 7 deletions
diff --git a/src/https.rs b/src/https.rs
index 5f8a17e..9d92470 100644
--- a/src/https.rs
+++ b/src/https.rs
@@ -24,7 +24,7 @@ use tokio_util::io::{ReaderStream, StreamReader};
 use opentelemetry::{metrics, KeyValue};
 
 use crate::cert_store::{CertStore, StoreResolver};
-use crate::proxy_config::{ProxyConfig, ProxyEntry};
+use crate::proxy_config::{HostDescription, ProxyConfig, ProxyEntry};
 use crate::reverse_proxy;
 
 const MAX_CONNECTION_LIFETIME: Duration = Duration::from_secs(24 * 3600);
@@ -272,15 +272,22 @@ async fn select_target_and_proxy(
 		);
 		proxy_to.calls_in_progress.fetch_add(1, Ordering::SeqCst);
 
+		// Forward to backend
 		debug!("{}{} -> {}", host, path, proxy_to);
 		trace!("Request: {:?}", req);
 
-		let response = match do_proxy(https_config, remote_addr, req, proxy_to).await {
-			Ok(resp) => resp,
-			Err(e) => Response::builder()
-				.status(StatusCode::BAD_GATEWAY)
-				.body(Body::from(format!("Proxy error: {}", e)))
-				.unwrap(),
+		let response = if let Some(http_res) = try_redirect(host, path, proxy_to) {
+			// redirection middleware
+			http_res
+		} else {
+			// proxying to backend
+			match do_proxy(https_config, remote_addr, req, proxy_to).await {
+				Ok(resp) => resp,
+				Err(e) => Response::builder()
+					.status(StatusCode::BAD_GATEWAY)
+					.body(Body::from(format!("Proxy error: {}", e)))
+					.unwrap(),
+			}
 		};
 
 		proxy_to.calls_in_progress.fetch_sub(1, Ordering::SeqCst);
@@ -302,6 +309,51 @@ async fn select_target_and_proxy(
 	}
 }
 
+fn try_redirect(req_host: &str, req_path: &str, proxy_to: &ProxyEntry) -> Option<Response<Body>> {
+	let maybe_redirect = proxy_to.redirects.iter().find(|(src, _, _)| {
+		let mut matched: bool = src.host.matches(req_host);
+
+		if let Some(path) = &src.path_prefix {
+			matched &= req_path.starts_with(path);
+		}
+
+		matched
+	});
+
+	let (src_prefix, dst_prefix, code) = match maybe_redirect {
+		None => return None,
+		Some(redirect) => redirect,
+	};
+
+	let new_host = match &dst_prefix.host {
+		HostDescription::Hostname(h) => h,
+		_ => unreachable!(), // checked when ProxyEntry is created
+	};
+
+	let new_prefix = dst_prefix.path_prefix.as_deref().unwrap_or("");
+	let original_prefix = src_prefix.path_prefix.as_deref().unwrap_or("");
+	let suffix = &req_path[original_prefix.len()..];
+
+	let uri = format!("https://{}{}{}", new_host, new_prefix, suffix);
+
+	let status = match StatusCode::from_u16(*code) {
+		Err(e) => {
+			warn!(
+				"Couldn't redirect {}{} to {} as code {} in invalid: {}",
+				req_host, req_path, uri, code, e
+			);
+			return None;
+		}
+		Ok(sc) => sc,
+	};
+
+	Response::builder()
+		.header("Location", uri.clone())
+		.status(status)
+		.body(Body::from(uri))
+		.ok()
+}
+
 async fn do_proxy(
 	https_config: &HttpsConfig,
 	remote_addr: SocketAddr,