Make MongoShell ready message handler backwards compatible (#606)

* Make MongShell message handler backwards compatible

* Fix test title and add one more test case

src/Explorer/Tabs/MongoShellTab.ts

@@ -6,11 +6,11 @@ import * as ViewModels from "../../Contracts/ViewModels";
 import { Action, ActionModifiers } from "../../Shared/Telemetry/TelemetryConstants";
 import * as TelemetryProcessor from "../../Shared/Telemetry/TelemetryProcessor";
 import { userContext } from "../../UserContext";
-import { isInvalidParentFrameOrigin } from "../../Utils/MessageValidation";
+import { isInvalidParentFrameOrigin, isReadyMessage } from "../../Utils/MessageValidation";
 import * as NotificationConsoleUtils from "../../Utils/NotificationConsoleUtils";
 import Explorer from "../Explorer";
-import template from "./MongoShellTab.html";
 import { ConsoleDataType } from "../Menus/NotificationConsole/NotificationConsoleComponent";
+import template from "./MongoShellTab.html";
 import TabsBase from "./TabsBase";
 
 export default class MongoShellTab extends TabsBase {
@@ -85,10 +85,7 @@ export default class MongoShellTab extends TabsBase {
   }
 
   private handleReadyMessage(event: MessageEvent, shellIframe: HTMLIFrameElement) {
-    if (typeof event.data["kind"] !== "string") {
+    if (!isReadyMessage(event)) {
-      return;
-    }
-    if (event.data.kind !== "ready") {
       return;
     }
 

src/Utils/MessageValidation.test.ts

@@ -1,6 +1,7 @@
-import { isInvalidParentFrameOrigin } from "./MessageValidation";
+import { isInvalidParentFrameOrigin, isReadyMessage } from "./MessageValidation";
 
-test.each`
+describe("isInvalidParentFrameOrigin", () => {
+  test.each`
     domain                                                           | expected
     ${"https://cosmos.azure.com"}                                    | ${false}
     ${"https://cosmos.azure.us"}                                     | ${false}
@@ -21,6 +22,23 @@ test.each`
     ${"https://malicious.germanycentral.cloudapp.microsoftazure.de"} | ${true}
     ${"https://maliciousazure.com"}                                  | ${true}
     ${"https://maliciousportalsazure.com"}                           | ${true}
-`("returns $expected when called with $domain", ({ domain, expected }) => {
+  `("returns $expected when called with $domain", ({ domain, expected }) => {
     expect(isInvalidParentFrameOrigin({ origin: domain } as MessageEvent)).toBe(expected);
+  });
+});
+
+describe("isReadyMessage", () => {
+  test.each`
+    event                                                 | expected
+    ${{ data: { kind: "ready" } }}                        | ${true}
+    ${{ data: { data: "ready" } }}                        | ${true}
+    ${{ data: { data: "ready", kind: "ready" } }}         | ${true}
+    ${{ data: { kind: "not-ready" } }}                    | ${false}
+    ${{ data: { data: "not-ready" } }}                    | ${false}
+    ${{ data: { data: "not-ready", kind: "not-ready" } }} | ${false}
+    ${{ data: {} }}                                       | ${false}
+    ${{}}                                                 | ${false}
+  `("returns $expected when called with $event", ({ event, expected }) => {
+    expect(isReadyMessage(event as MessageEvent)).toBe(expected);
+  });
 });

src/Utils/MessageValidation.ts

@@ -20,3 +20,15 @@ function isValidOrigin(allowedOrigins: string[], event: MessageEvent): boolean {
   console.error(`Invalid parent frame origin detected: ${eventOrigin}`);
   return false;
 }
+
+export function isReadyMessage(event: MessageEvent): boolean {
+  if (!event?.data?.kind && !event?.data?.data) {
+    return false;
+  }
+
+  if (event.data.kind !== "ready" && event.data.data !== "ready") {
+    return false;
+  }
+
+  return true;
+}