Fix GET/HEAD request bodies failing before the handler

package.json

@@ -1,6 +1,6 @@
 {
     "name": "@azure/functions",
-    "version": "4.16.2",
+    "version": "4.16.3",
     "description": "Microsoft Azure Functions NodeJS Framework",
     "keywords": [
         "azure",

src/constants.ts

@@ -1,6 +1,6 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the MIT License.
 
-export const version = '4.16.2';
+export const version = '4.16.3';
 
 export const returnBindingKey = '$return';

src/http/HttpRequest.ts

@@ -13,6 +13,7 @@ import { fromNullableMapping } from '../converters/fromRpcNullable';
 import { fromRpcTypedData } from '../converters/fromRpcTypedData';
 import { AzFuncSystemError } from '../errors';
 import { isDefined, nonNullProp } from '../utils/nonNull';
+import { workerSystemLog } from '../utils/workerSystemLog';
 import { extractHttpUserFromHeaders } from './extractHttpUserFromHeaders';
 
 interface InternalHttpRequestInit extends RpcHttpData {
@@ -33,17 +34,31 @@ export class HttpRequest implements types.HttpRequest {
         let nativeReq = init.nativeRequest;
         if (!nativeReq) {
             const url = nonNullProp(init, 'url');
+            const method = nonNullProp(init, 'method');
 
+            // GET/HEAD requests cannot have a body. The global Request constructor throws if one is
+            // provided, so omit it for these methods to match the streaming path (createStreamRequest).
+            // See https://github.com/Azure/azure-functions-nodejs-library/issues/458
             let body: Buffer | string | undefined;
-            if (init.body?.bytes) {
-                body = Buffer.from(init.body?.bytes);
-            } else if (init.body?.string) {
-                body = init.body.string;
+            const lowerMethod = method.toLowerCase();
+            if (lowerMethod !== 'get' && lowerMethod !== 'head') {
+                if (init.body?.bytes) {
+                    body = Buffer.from(init.body?.bytes);
+                } else if (init.body?.string) {
+                    body = init.body.string;
+                }
+            } else if (init.body?.bytes?.length || init.body?.string) {
+                // The incoming GET/HEAD request has a body, which the global Request constructor forbids.
+                // We drop it to avoid crashing, but log it so the behavior isn't silent and is easier to debug.
+                workerSystemLog(
+                    'warning',
+                    `Discarding the body of the incoming ${method} request because GET and HEAD requests cannot have a body.`
+                );
             }
 
             nativeReq = new Request(url, {
                 body,
-                method: nonNullProp(init, 'method'),
+                method,
                 headers: fromNullableMapping(init.nullableHeaders, init.headers),
             });
         }

src/http/HttpResponse.ts

@@ -11,6 +11,10 @@ interface InternalHttpResponseInit extends HttpResponseInit {
     nativeResponse?: Response;
 }
 
+// Statuses that cannot have a body per the WHATWG fetch spec ("null body status"), limited to the
+// valid Response status range (200-599). The global Response constructor throws if a body is provided.
+const nullBodyStatuses = new Set([204, 205, 304]);
+
 export class HttpResponse implements types.HttpResponse {
     readonly cookies: types.Cookie[];
     readonly enableContentNegotiation: boolean;
@@ -26,7 +30,12 @@ export class HttpResponse implements types.HttpResponse {
             this.#nativeRes = init.nativeResponse;
         } else {
             const resInit: ResponseInit = { status: init.status, headers: init.headers };
-            if (isDefined(init.jsonBody)) {
+            // 204/205/304 responses cannot have a body. The global Response constructor throws if one
+            // is provided, so omit it to avoid crashing when converting a handler's response. This
+            // mirrors the GET/HEAD body handling in HttpRequest.
+            // See https://github.com/Azure/azure-functions-nodejs-library/issues/458
+            const isNullBodyStatus = isDefined(init.status) && nullBodyStatuses.has(init.status);
+            if (isDefined(init.jsonBody) && !isNullBodyStatus) {
                 // Response.json is not available in all versions, so we create it manually
                 const jsonBody = JSON.stringify(init.jsonBody);
                 const jsonHeaders = new Headers(resInit.headers);
@@ -38,7 +47,7 @@ export class HttpResponse implements types.HttpResponse {
                 // Cast to any to satisfy the native Response constructor
                 // Our HttpResponseBodyInit type is compatible with what Node.js accepts
                 // eslint-disable-next-line @typescript-eslint/no-unsafe-argument
-                this.#nativeRes = new Response(init.body as any, resInit);
+                this.#nativeRes = new Response(isNullBodyStatus ? undefined : (init.body as any), resInit);
             }
         }
 

test/converters/toRpcHttp.test.ts

@@ -95,6 +95,23 @@ describe('toRpcHttp', () => {
         await expect(toRpcHttp('invocId', { status: {} })).to.eventually.be.rejectedWith(/status/i);
     });
 
+    // https://github.com/Azure/azure-functions-nodejs-library/issues/458 (Response-side parallel):
+    // null-body statuses must not crash conversion when a handler returns a body.
+    it('status 204 with a body converts to an empty body', async () => {
+        const result = await toRpcHttp('invocId', { status: 204, body: 'dropped' });
+        expect(result).to.deep.equal(getExpectedRpcHttp('', {}, '204'));
+    });
+
+    it('status 205 with a body converts to an empty body', async () => {
+        const result = await toRpcHttp('invocId', { status: 205, body: 'dropped' });
+        expect(result).to.deep.equal(getExpectedRpcHttp('', {}, '205'));
+    });
+
+    it('status 304 with a jsonBody converts to an empty body', async () => {
+        const result = await toRpcHttp('invocId', { status: 304, jsonBody: { a: 1 } });
+        expect(result).to.deep.equal(getExpectedRpcHttp('', {}, '304'));
+    });
+
     it('headers object', async () => {
         const result = await toRpcHttp('invocId', {
             headers: {