fix: improve node middleware handling

Author: pi0

src/adapters.ts

@@ -8,6 +8,7 @@ import type {
 } from "./types";
 import { toNodeHandler as _toNodeHandler } from "srvx/node";
 import { createError } from "./error";
+import { kHandled } from "./response";
 
 export function toWebHandler(
   app: H3,
@@ -72,23 +73,24 @@ function callNodeHandler(
 ) {
   const isMiddleware = handler.length > 2;
   return new Promise((resolve, reject) => {
-    const next = (err?: Error) => {
-      if (isMiddleware) {
-        res.off("close", next);
-        res.off("error", next);
-      }
-      return err ? reject(createError(err)) : resolve(undefined);
-    };
+    res.once("close", () => resolve(kHandled));
+    res.once("finish", () => resolve(kHandled));
+    res.once("pipe", () => resolve(kHandled));
+    res.once("error", (error) => reject(error));
     try {
-      const returned = handler(req, res, next);
-      if (isMiddleware && returned === undefined) {
-        res.once("close", next);
-        res.once("error", next);
+      if (isMiddleware) {
+        Promise.resolve(
+          handler(req, res, (err) =>
+            err ? reject(createError(err)) : resolve(void 0),
+          ),
+        ).catch((error) => reject(createError(error)));
       } else {
-        resolve(returned);
+        return Promise.resolve((handler as NodeHandler)(req, res))
+          .then(() => resolve(kHandled))
+          .catch((error) => reject(createError(error)));
       }
-    } catch (error) {
-      next(error as Error);
+    } catch (error: any) {
+      reject(createError(error));
     }
   });
 }

src/response.ts

@@ -6,6 +6,7 @@ import { createError } from "./error";
 import { isJSONSerializable } from "./utils/internal/object";
 
 export const kNotFound = /* @__PURE__ */ Symbol.for("h3.notFound");
+export const kHandled = /* @__PURE__ */ Symbol.for("h3.handled");
 
 export function prepareResponse(
   val: unknown,
@@ -14,6 +15,10 @@ export function prepareResponse(
 ): Response {
   const isHead = event.method === "HEAD";
 
+  if (val === kHandled) {
+    return new Response(null);
+  }
+
   if (val instanceof Response) {
     const we = event as H3WebEvent;
     const status = we.response.status;

test/integrations.test.ts

@@ -57,10 +57,14 @@ describeMatrix("integrations", (t, { it, expect, describe }) => {
       t.app.use(
         "/api/hello",
         fromNodeHandler(
-          defineNodeHandler((req, res) => ({
-            url: req.url,
-            prop: (res as any).prop,
-          })),
+          defineNodeHandler((req, res) => {
+            res.end(
+              JSON.stringify({
+                url: req.url,
+                prop: (res as any).prop,
+              }),
+            );
+          }),
         ),
       );
       expressApp.use("/api", toNodeHandler(t.app) as any);
@@ -93,10 +97,16 @@ describeMatrix("integrations", (t, { it, expect, describe }) => {
       );
       t.app.use(
         "/api/hello",
-        fromNodeHandler((req, res) => ({
-          url: req.url,
-          prop: (res as any).prop,
-        })),
+        fromNodeHandler(
+          defineNodeHandler((req, res) => {
+            res.end(
+              JSON.stringify({
+                url: req.url,
+                prop: (res as any).prop,
+              }),
+            );
+          }),
+        ),
       );
       connectApp.use("/api", toNodeHandler(t.app));