Fix

src/main.rs

@@ -1,5 +1,5 @@
 use std::{net::SocketAddr, time::SystemTime};
-use axum::{Router, routing::{post, get}, extract::Multipart, response::{IntoResponse, AppendHeaders}, http::{StatusCode, header}, body::StreamBody};
+use axum::{Router, routing::{post, get}, extract::Multipart, response::{IntoResponse, AppendHeaders, Response}, http::{StatusCode, header, Request, self}, body::StreamBody, middleware::{Next, self}};
 use axum_prometheus::PrometheusMetricLayer;
 use tokio::{fs::{remove_file, read_dir, remove_dir, File}, io::{AsyncWriteExt, copy}, process::Command};
 use tower_http::trace::{TraceLayer, self};
@@ -161,13 +161,40 @@ async fn convert_file(
 }
 
 
+async fn auth<B>(req: Request<B>, next: Next<B>) -> Result<Response, StatusCode> {
+    let auth_header = req
+        .headers()
+        .get(http::header::AUTHORIZATION)
+        .and_then(|header| header.to_str().ok());
+
+    let auth_header = if let Some(auth_header) = auth_header {
+        auth_header
+    } else {
+        return Err(StatusCode::UNAUTHORIZED);
+    };
+
+    if auth_header != std::env::var("API_KEY").unwrap_or_else(|_| panic!("Cannot get the API_KEY env variable")) {
+        return Err(StatusCode::UNAUTHORIZED);
+    }
+
+    Ok(next.run(req).await)
+}
+
+
 fn get_router() -> Router {
     let (prometheus_layer, metric_handle) = PrometheusMetricLayer::pair();
 
-    Router::new()
+    let app_router = Router::new()
         .route("/", post(convert_file))
-        .route("/metrics", get(|| async move { metric_handle.render() }))
+        .layer(middleware::from_fn(auth))
-        .layer(prometheus_layer)
+        .layer(prometheus_layer);
+
+    let metric_router =
+        Router::new().route("/metrics", get(|| async move { metric_handle.render() }));
+
+    Router::new()
+        .nest("/", app_router)
+        .nest("/", metric_router)
         .layer(
             TraceLayer::new_for_http()
                 .make_span_with(trace::DefaultMakeSpan::new().level(Level::INFO))