proxy-backend support sse connections closing

Signed-off-by: Nina Berg <nikb100@gmail.com>
2025-04-07 11:30:24 -04:00
parent d67fd32c6b
commit d65ec54f23
1 changed files with 14 additions and 2 deletions
@@ -214,8 +214,12 @@ export function buildMiddleware(
    ].map(h => h.toLocaleLowerCase()),
  );

-  // only forward the allowed headers in backend->client
-  fullConfig.onProxyRes = (proxyRes: http.IncomingMessage) => {
+  fullConfig.onProxyRes = (
+    proxyRes: http.IncomingMessage,
+    _,
+    res: express.Response,
+  ) => {
+    // only forward the allowed headers in backend->client
    const headerNames = Object.keys(proxyRes.headers);

    headerNames.forEach(h => {
@@ -223,6 +227,14 @@ export function buildMiddleware(
        delete proxyRes.headers[h];
      }
    });
+
+    // handle SSE connections closed by the backend
+    // https://github.com/chimurai/http-proxy-middleware/discussions/765
+    proxyRes.on('close', () => {
+      if (!res.writableEnded) {
+        res.end();
+      }
+    });
  };

  if (reviveConsumedRequestBodies) {