fix: dont use node request as body in handleServerFunction (#1577)

.changeset/chilled-phones-sin.md

@@ -0,0 +1,5 @@
+---
+"@solidjs/start": patch
+---
+
+Fixed a regression that resulted in an `Response body object should not be disturbed or locked` error during form body parsing.

packages/start/src/runtime/server-handler.ts

@@ -119,8 +119,17 @@ async function handleServerFunction(h3Event: HTTPEvent) {
   }
   if (h3Event.method === "POST") {
     const contentType = request.headers.get("content-type");
-    const h3EventBody = h3Event.node.req as any;
-    const isH3EventBodyStreamLocked = h3EventBody instanceof ReadableStream && h3EventBody.locked;
+
+    // Nodes native IncomingMessage doesn't have a body,
+    // But we need to access it for some reason (#1282)
+    type EdgeIncomingMessage = typeof h3Event.node.req & { body?: BodyInit };
+    const h3Request = h3Event.node.req as EdgeIncomingMessage | ReadableStream;
+
+    // This should never be the case in "proper" Nitro presets since node.req has to be IncomingMessage,
+    // But the new azure-functions preset for some reason uses a ReadableStream in node.req (#1521)
+    const isReadableStream = h3Request instanceof ReadableStream;
+    const isH3EventBodyStreamLocked = isReadableStream && h3Request.locked;
+    const requestBody = isReadableStream ? h3Request : h3Request.body;
 
     if (
       contentType?.startsWith("multipart/form-data") ||
@@ -129,10 +138,10 @@ async function handleServerFunction(h3Event: HTTPEvent) {
       // workaround for https://github.com/unjs/nitro/issues/1721
       // (issue only in edge runtimes)
       parsed.push(
-        await (
+        await(
           isH3EventBodyStreamLocked
             ? request
-            : new Request(request, { ...request, body: h3EventBody })
+            : new Request(request, { ...request, body: requestBody })
         ).formData()
       );
       // what should work when #1721 is fixed
@@ -142,7 +151,7 @@ async function handleServerFunction(h3Event: HTTPEvent) {
       // (issue only in edge runtimes)
       const tmpReq = isH3EventBodyStreamLocked
         ? request
-        : new Request(request, { ...request, body: h3EventBody });
+        : new Request(request, { ...request, body: requestBody });
       // what should work when #1721 is fixed
       // just use request.json() here
       parsed = fromJSON(await tmpReq.json(), {