Merge pull request #5737 from Turbo87/axum-route-blocking

Implement `block_traffic::block_routes` middleware

Author: Turbo87

src/middleware.rs

@@ -71,6 +71,10 @@ pub fn apply_axum_middleware(state: AppState, router: Router) -> Router {
             state.clone(),
             block_traffic::block_traffic,
         ))
+        .layer(from_fn_with_state(
+            state.clone(),
+            block_traffic::block_routes,
+        ))
         .layer(from_fn(head::support_head_requests))
         .layer(HandleErrorLayer::new(dummy_error_handler))
         .option_layer(

src/middleware/block_traffic.rs

@@ -10,7 +10,8 @@
 
 use super::prelude::*;
 use crate::app::AppState;
-use axum::extract::State;
+use crate::util::errors::RouteBlocked;
+use axum::extract::{MatchedPath, State};
 use axum::middleware::Next;
 use axum::response::IntoResponse;
 
@@ -53,3 +54,20 @@ pub async fn block_traffic<B>(
 
     next.run(req).await
 }
+
+/// Allow blocking individual routes by their pattern through the `BLOCKED_ROUTES`
+/// environment variable.
+pub async fn block_routes<B>(
+    matched_path: Option<MatchedPath>,
+    State(state): State<AppState>,
+    req: http::Request<B>,
+    next: Next<B>,
+) -> axum::response::Response {
+    if let Some(matched_path) = matched_path {
+        if state.config.blocked_routes.contains(matched_path.as_str()) {
+            return RouteBlocked.into_response();
+        }
+    }
+
+    next.run(req).await
+}

src/util/errors/json.rs

@@ -1,3 +1,5 @@
+use axum::response::{IntoResponse, Response};
+use axum::Json;
 use std::fmt;
 
 use super::{AppError, InternalAppErrorStatic};
@@ -286,3 +288,10 @@ impl fmt::Display for RouteBlocked {
         f.write_str("This route is temporarily blocked. See https://status.crates.io.")
     }
 }
+
+impl IntoResponse for RouteBlocked {
+    fn into_response(self) -> Response {
+        let body = Json(json!({ "errors": [{ "detail": self.to_string() }] }));
+        (StatusCode::SERVICE_UNAVAILABLE, body).into_response()
+    }
+}