Fix return output binding logic (Azure#264)

* updates to make 2.0 worker 1.0 compatible

* split validation logic so it's both v1 and v2 compatible

* hard-coded solution to camelCase timer trigger while proper fix is out of scope for timeline

* added test

* adding unit test

* properly convert data when defined as output array

* testing both v1 behavior and v2 behavior

* dont code without intellisense

* remove e2e test until have better test on functions host v2 and v3

* fix worker validation logic and warning message on ts changes

* add tests

scripts/generateProtos.js

@@ -22,7 +22,9 @@ async function generateProtos() {
         .catch(err => console.log(`Could not compile to JavaScript: ${err}`));
 
     // Don't generate with Node.js v12 until resolved: https://github.com/protobufjs/protobuf.js/issues/1275
-    if (!process.version.startsWith("v12")) {
+    if (process.version.startsWith("v12") && process.platform === 'win32') {
+        console.warn("Warning! Could not compile to TypeScript for Node.js 12 and Windows OS. Do not change public interfaces.");
+    } else {
         genTs(allFiles)
         .then(data => console.log("Compiled to TypeScript."))
         .catch(err => console.log(`Could not compile to TypeScript: ${err}`));

src/WorkerChannel.ts

@@ -99,13 +99,11 @@ export class WorkerChannel implements IWorkerChannel {
     // Validate version
     let version = process.version;
     if (this._v1WorkerBehavior) {
-      if (version.startsWith("v12."))
-      {
+      if (version.startsWith("v12.")) {
         systemWarn("The Node.js version you are using (" + version + ") is not fully supported with Azure Functions V2. We recommend using one the following major versions: 8, 10.");
       }
     } else {
-      if (version.startsWith("v8."))
-      {
+      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;
@@ -192,10 +190,22 @@ export class WorkerChannel implements IWorkerChannel {
               response.returnValue = toTypedData(result.return);
             } else {
               let returnBinding = info.getReturnBinding();
-              response.returnValue = returnBinding ? returnBinding.converter(result.return) : toTypedData(result.return);
+              // $return binding is found: return result data to $return binding
+              if (returnBinding) {
+                response.returnValue = returnBinding.converter(result.return);
+              // $return binding is not found: read result as object of outputs
+              } else if (result.return) {
+                response.outputData = Object.keys(info.outputBindings)
+                  .filter(key => result.return[key] !== undefined)
+                  .map(key => <rpc.IParameterBinding>{
+                    name: key,
+                    data: info.outputBindings[key].converter(result.return[key])
+                  });
+              }
             }
           }
-          if (result.bindings) {
+          // Data from return supersedes data from context.bindings
+          if (result.bindings && !response.outputData) {
             response.outputData = Object.keys(info.outputBindings)
               .filter(key => result.bindings[key] !== undefined)
               .map(key => <rpc.IParameterBinding>{
@@ -207,7 +217,6 @@ export class WorkerChannel implements IWorkerChannel {
       } catch (e) {
         response.result = this.getStatus(e)
       }
-
       this._eventStream.write({
         requestId: requestId,
         invocationResponse: response