[fix] prevent responses from hanging

Author: benmccann

Diff for: .changeset/few-teachers-deliver.md

@@ -0,0 +1,10 @@
+---
+'@sveltejs/adapter-node': patch
+'@sveltejs/kit': patch
+'@sveltejs/adapter-cloudflare': patch
+'@sveltejs/adapter-cloudflare-workers': patch
+'@sveltejs/adapter-netlify': patch
+'@sveltejs/adapter-vercel': patch
+---
+
+[fix] prevent responses from hanging

Diff for: packages/adapter-node/package.json

@@ -42,12 +42,12 @@
 		"@types/node": "^16.11.36",
 		"c8": "^7.11.3",
 		"compression": "^1.7.4",
-		"node-fetch": "^3.2.4",
 		"polka": "^1.0.0-next.22",
 		"rimraf": "^3.0.2",
 		"rollup": "^2.75.3",
 		"sirv": "^2.0.2",
 		"typescript": "^4.7.4",
+		"undici": "^5.6.1",
 		"uvu": "^0.5.3"
 	}
 }

Diff for: packages/adapter-node/tests/smoke.js

@@ -1,8 +1,8 @@
 import { test } from 'uvu';
 import { create_kit_middleware } from '../src/handler.js';
-import * as assert from 'uvu/assert';
-import fetch from 'node-fetch';
 import polka from 'polka';
+import * as assert from 'uvu/assert';
+import { fetch } from 'undici';
 
 const { PORT = 3000 } = process.env;
 const DEFAULT_SERVER_OPTS = { render: () => {} };

Diff for: packages/kit/src/node/index.js

@@ -89,38 +89,12 @@ export async function setResponse(res, response) {
 
 	res.writeHead(response.status, headers);
 
-	if (response.body) {
-		let cancelled = false;
-
-		const reader = response.body.getReader();
-
-		res.on('close', () => {
-			reader.cancel();
-			cancelled = true;
-		});
-
-		const next = async () => {
-			const { done, value } = await reader.read();
-
-			if (cancelled) return;
-
-			if (done) {
-				res.end();
-				return;
-			}
-
-			res.write(Buffer.from(value), (error) => {
-				if (error) {
-					console.error('Error writing stream', error);
-					res.end();
-				} else {
-					next();
-				}
-			});
-		};
-
-		next();
+	if (response.body instanceof Readable) {
+		response.body.pipe(res);
 	} else {
+		if (response.body) {
+			res.write(new Uint8Array(await response.arrayBuffer()));
+		}
 		res.end();
 	}
 }