Throw more helpful error if http output is incorrect

src/WorkerChannel.ts

@@ -106,7 +106,7 @@ export class WorkerChannel implements IWorkerChannel {
       if (version.startsWith("v8.")) {
         let msg = "Incompatible Node.js version. The version you are using (" + version + ") is not supported with Azure Functions V3. Please use one of the following major versions: 10, 12.";
         systemError(msg);
-        throw msg;
+        throw new InternalException(msg);
       }
     }
 

src/converters/RpcHttpConverters.ts

@@ -52,6 +52,11 @@ function fromRpcHttpBody(body: rpc.ITypedData) {
  * @param inputMessage  An HTTP response object
  */
 export function toRpcHttp(inputMessage): rpc.ITypedData {
+    // Check if we will fail to find any of these
+    if (typeof inputMessage !== 'object' || Array.isArray(inputMessage)) {
+        throw new Error("The HTTP response must be an 'object' type that can include properties such as 'body', 'status', and 'headers'. Learn more: https://go.microsoft.com/fwlink/?linkid=2112563");
+    }
+
     let httpMessage: rpc.IRpcHttp = inputMessage;
     httpMessage.headers = toRpcHttpHeaders(inputMessage.headers);
     httpMessage.cookies = toRpcHttpCookieList(inputMessage.cookies || []);

test/RpcHttpConverters.ts

@@ -1,4 +1,4 @@
-import { toRpcHttpCookieList } from '../src/converters';
+import { toRpcHttpCookieList, toRpcHttp } from '../src/converters';
 import { Cookie } from "../types/public/Interfaces";
 import { expect } from 'chai';
 import * as sinon from 'sinon';
@@ -43,7 +43,7 @@ describe('Rpc Converters', () => {
     expect((<any>rpcCookies[2].expires).value.seconds).to.equal(819199440);
   });
 
-  it('throws on invalid input', () => {
+  it('throws on invalid cookie input', () => {
       expect(() => {
         let cookieInputs = [
                 {
@@ -72,4 +72,18 @@ describe('Rpc Converters', () => {
         toRpcHttpCookieList(<Cookie[]>cookieInputs);
       }).to.throw("");
   });
+
+  it('throws on array as http response', () => {
+    expect(() => {
+      let response = ["one", 2, "3"];
+      toRpcHttp(response);
+    }).to.throw("The HTTP response must be an 'object' type that can include properties such as 'body', 'status', and 'headers'. Learn more: https://go.microsoft.com/fwlink/?linkid=2112563");
+  });
+
+  it('throws on string as http response', () => {
+      expect(() => {
+      let response = "My output string";
+      toRpcHttp(response);
+      }).to.throw("The HTTP response must be an 'object' type that can include properties such as 'body', 'status', and 'headers'. Learn more: https://go.microsoft.com/fwlink/?linkid=2112563");
+  });
 })