Added headless mode start option (#3065)

* Added headless mode start option. Fixes #3064

src/MCT.js

@@ -249,7 +249,7 @@ define([
         this.legacyRegistry = new BundleRegistry();
         installDefaultBundles(this.legacyRegistry);
 
-        // Plugin's that are installed by default
+        // Plugins that are installed by default
 
         this.install(this.plugins.Plot());
         this.install(this.plugins.TelemetryTable());
@@ -350,17 +350,13 @@ define([
      * @param {HTMLElement} [domElement] the DOM element in which to run
      *        MCT; if undefined, MCT will be run in the body of the document
      */
-    MCT.prototype.start = function (domElement) {
+    MCT.prototype.start = function (domElement = document.body, isHeadlessMode = false) {
         if (!this.plugins.DisplayLayout._installed) {
             this.install(this.plugins.DisplayLayout({
                 showAsView: ['summary-widget']
             }));
         }
 
-        if (!domElement) {
-            domElement = document.body;
-        }
-
         this.element = domElement;
 
         this.legacyExtension('runs', {
@@ -400,24 +396,31 @@ define([
                 // something has depended upon objectService.  Cool, right?
                 this.$injector.get('objectService');
 
-                var appLayout = new Vue({
-                    components: {
-                        'Layout': Layout.default
-                    },
-                    provide: {
-                        openmct: this
-                    },
-                    template: '<Layout ref="layout"></Layout>'
-                });
-                domElement.appendChild(appLayout.$mount().$el);
+                if (!isHeadlessMode) {
+                    var appLayout = new Vue({
+                        components: {
+                            'Layout': Layout.default
+                        },
+                        provide: {
+                            openmct: this
+                        },
+                        template: '<Layout ref="layout"></Layout>'
+                    });
+                    domElement.appendChild(appLayout.$mount().$el);
 
-                this.layout = appLayout.$refs.layout;
-                Browse(this);
+                    this.layout = appLayout.$refs.layout;
+                    Browse(this);
+                }
                 this.router.start();
                 this.emit('start');
             }.bind(this));
     };
 
+    MCT.prototype.startHeadless = function () {
+        let unreachableNode = document.createElement('div');
+        return this.start(unreachableNode, true);
+    }
+
     /**
      * Install a plugin in MCT.
      *

src/MCTSpec.js

@@ -21,11 +21,11 @@
  *****************************************************************************/
 
 define([
-    './MCT',
     './plugins/plugins',
-    'legacyRegistry'
-], function (MCT, plugins, legacyRegistry) {
-    xdescribe("MCT", function () {
+    'legacyRegistry',
+    'testTools'
+], function (plugins, legacyRegistry, testTools) {
+    describe("MCT", function () {
         var openmct;
         var mockPlugin;
         var mockPlugin2;
@@ -38,7 +38,7 @@ define([
             mockListener = jasmine.createSpy('listener');
             oldBundles = legacyRegistry.list();
 
-            openmct = new MCT();
+            openmct = testTools.createOpenMct();
 
             openmct.install(mockPlugin);
             openmct.install(mockPlugin2);
@@ -63,8 +63,11 @@ define([
         });
 
         describe("start", function () {
-            beforeEach(function () {
-                openmct.start();
+            let appHolder;
+            beforeEach(function (done) {
+                appHolder = document.createElement("div");
+                openmct.on('start', done);
+                openmct.start(appHolder);
             });
 
             it("calls plugins for configuration", function () {
@@ -75,25 +78,51 @@ define([
             it("emits a start event", function () {
                 expect(mockListener).toHaveBeenCalled();
             });
+
+            it("Renders the application into the provided container element", function () {
+                let openMctShellElements = appHolder.querySelectorAll('div.l-shell');
+                expect(openMctShellElements.length).toBe(1);
+            });
+        });
+
+        describe("startHeadless", function () {
+            beforeEach(function (done) {
+                openmct.on('start', done);
+                openmct.startHeadless();
+            });
+
+            it("calls plugins for configuration", function () {
+                expect(mockPlugin).toHaveBeenCalledWith(openmct);
+                expect(mockPlugin2).toHaveBeenCalledWith(openmct);
+            });
+
+            it("emits a start event", function () {
+                expect(mockListener).toHaveBeenCalled();
+            });
+
+            it("Does not render Open MCT", function () {
+                let openMctShellElements = document.body.querySelectorAll('div.l-shell');
+                expect(openMctShellElements.length).toBe(0);
+            });
         });
 
         describe("setAssetPath", function () {
             var testAssetPath;
 
             beforeEach(function () {
-                testAssetPath = "some/path";
                 openmct.legacyExtension = jasmine.createSpy('legacyExtension');
-                openmct.setAssetPath(testAssetPath);
             });
 
-            it("internally configures the path for assets", function () {
-                expect(openmct.legacyExtension).toHaveBeenCalledWith(
-                    'constants',
-                    {
-                        key: "ASSETS_PATH",
-                        value: testAssetPath
-                    }
-                );
+            it("configures the path for assets", function () {
+                testAssetPath = "some/path/";
+                openmct.setAssetPath(testAssetPath);
+                expect(openmct.getAssetPath()).toBe(testAssetPath);
+            });
+
+            it("adds a trailing /", function () {
+                testAssetPath = "some/path";
+                openmct.setAssetPath(testAssetPath);
+                expect(openmct.getAssetPath()).toBe(testAssetPath + "/");
             });
         });
     });

src/plugins/condition/pluginSpec.js

@@ -23,22 +23,18 @@
 import { createOpenMct } from "testTools";
 import ConditionPlugin from "./plugin";
 
-let openmct = createOpenMct();
-openmct.install(new ConditionPlugin());
-
-let conditionSetDefinition;
-let mockConditionSetDomainObject;
-let element;
-let child;
-
 describe('the plugin', function () {
+    let conditionSetDefinition;
+    let mockConditionSetDomainObject;
+    let element;
+    let child;
+    let openmct;
 
     beforeAll((done) => {
+        openmct = createOpenMct();
+        openmct.install(new ConditionPlugin());
 
         conditionSetDefinition = openmct.types.get('conditionSet').definition;
-        const appHolder = document.createElement('div');
-        appHolder.style.width = '640px';
-        appHolder.style.height = '480px';
 
         element = document.createElement('div');
         child = document.createElement('div');
@@ -55,7 +51,7 @@ describe('the plugin', function () {
         conditionSetDefinition.initialize(mockConditionSetDomainObject);
 
         openmct.on('start', done);
-        openmct.start(appHolder);
+        openmct.startHeadless();
     });
 
     let mockConditionSetObject = {

src/plugins/telemetryTable/pluginSpec.js

@@ -26,32 +26,37 @@ import {
     createMouseEvent
 } from 'testTools';
 
-let openmct;
-let tablePlugin;
-let element;
-let child;
-
 describe("the plugin", () => {
-    beforeEach((done) => {
-        const appHolder = document.createElement('div');
-        appHolder.style.width = '640px';
-        appHolder.style.height = '480px';
+    let openmct;
+    let tablePlugin;
+    let element;
+    let child;
 
+    beforeEach((done) => {
         openmct = createOpenMct();
 
+        // Table Plugin is actually installed by default, but because installing it
+        // again is harmless it is left here as an examplar for non-default plugins.
+        tablePlugin = new TablePlugin();
+        openmct.install(tablePlugin);
+
         element = document.createElement('div');
         child = document.createElement('div');
         element.appendChild(child);
 
-        tablePlugin = new TablePlugin();
-        openmct.install(tablePlugin);
-
         spyOn(openmct.telemetry, 'request').and.returnValue(Promise.resolve([]));
 
         openmct.on('start', done);
-        openmct.start(appHolder);
+        openmct.startHeadless();
     });
 
+    describe("defines a table object", function () {
+        it("that is creatable", () => {
+            let tableType = openmct.types.get('table');
+            expect(tableType.definition.creatable).toBe(true);
+        });
+    })
+
     it("provides a table view for objects with telemetry", () => {
         const testTelemetryObject = {
             id:"test-object",