[Search] Don't re-index from second window

...if another window has already completed indexing
of domain objects for in-memory search.

docs/src/guide/index.md

@@ -1254,6 +1254,21 @@ object, or the current view proxy.
 * `all()`: Get an array of all objects in the selection state. Will include 
 either or both of the view proxy and selected object. 
 
+## Workers Category
+
+The `workers` extension category allows scripts to be run as web workers
+using the `workerService`.
+
+An extension of this category has no implementation. The following properties
+are supported:
+
+* `key`: A symbolic string used to identify this worker.
+* `workerUrl`: The path, relative to this bundle's `src` folder, where
+  this worker's source code resides.
+* `shared`: Optional; a boolean flag which, if true, indicates that this
+  worker should be instantiated as a
+  [`SharedWorker`](https://developer.mozilla.org/en-US/docs/Web/API/SharedWorker/SharedWorker).
+
 # Directives
 
 Open MCT Web defines several Angular directives that are intended for use both 
@@ -1849,6 +1864,14 @@ the TelemetrySeries itself, in that order.
 * `getSeries(domainObject)`: Get the latest `TelemetrySeries` (as resulted from 
 a previous `request(...)` call) available for this domain object.
 
+### Worker Service
+
+The `workerService` may be used to run web workers defined via the
+`workers` extension category. It has the following method:
+
+* `run(key)`: Run the worker identified by the provided `key`. Returns
+  a `Worker` (or `SharedWorker`, if the specified worker is defined
+  as a shared worker); if the `key` is unknown, returns `undefined`.
 
 # Models
 Domain object models in Open MCT Web are JavaScript objects describing the 

platform/execution/src/WorkerService.js

@@ -38,7 +38,8 @@ define(
          * @constructor
          */
         function WorkerService($window, workers) {
-            var workerUrls = {};
+            var workerUrls = {},
+                sharedWorkers = {};
 
             function addWorker(worker) {
                 var key = worker.key;
@@ -48,12 +49,15 @@ define(
                         worker.bundle.sources,
                         worker.scriptUrl
                     ].join("/");
+                    sharedWorkers[key] = worker.shared;
                 }
             }
 
             (workers || []).forEach(addWorker);
             this.workerUrls = workerUrls;
+            this.sharedWorkers = sharedWorkers;
             this.Worker = $window.Worker;
+            this.SharedWorker = $window.SharedWorker;
         }
 
         /**
@@ -66,7 +70,8 @@ define(
          */
         WorkerService.prototype.run = function (key) {
             var scriptUrl = this.workerUrls[key],
-                Worker = this.Worker;
+                Worker = this.sharedWorkers[key] ?
+                        this.SharedWorker : this.Worker;
             return scriptUrl && Worker && new Worker(scriptUrl);
         };
 

platform/execution/test/WorkerServiceSpec.js

@@ -30,10 +30,14 @@ define(
             var mockWindow,
                 testWorkers,
                 mockWorker,
+                mockSharedWorker,
                 service;
 
             beforeEach(function () {
-                mockWindow = jasmine.createSpyObj('$window', ['Worker']);
+                mockWindow = jasmine.createSpyObj(
+                    '$window',
+                    ['Worker', 'SharedWorker']
+                );
                 testWorkers = [
                     {
                         key: 'abc',
@@ -49,11 +53,19 @@ define(
                         key: 'xyz',
                         scriptUrl: 'bad.js',
                         bundle: { path: 'bad', sources: 'bad' }
+                    },
+                    {
+                        key: 'a-shared-worker',
+                        shared: true,
+                        scriptUrl: 'c.js',
+                        bundle: { path: 'a', sources: 'b' }
                     }
                 ];
                 mockWorker = {};
+                mockSharedWorker = {};
 
                 mockWindow.Worker.andReturn(mockWorker);
+                mockWindow.SharedWorker.andReturn(mockSharedWorker);
 
                 service = new WorkerService(mockWindow, testWorkers);
             });
@@ -68,6 +80,12 @@ define(
                 expect(mockWindow.Worker).toHaveBeenCalledWith('x/y/z.js');
             });
 
+            it("allows workers to be shared", function () {
+                expect(service.run('a-shared-worker')).toBe(mockSharedWorker);
+                expect(mockWindow.SharedWorker)
+                    .toHaveBeenCalledWith('a/b/c.js');
+            });
+
             it("returns undefined for unknown workers", function () {
                 expect(service.run('def')).toBeUndefined();
             });

platform/search/bundle.json

@@ -66,7 +66,8 @@
         "workers": [
             {
                 "key": "genericSearchWorker",
-                "scriptUrl": "services/GenericSearchWorker.js"
+                "scriptUrl": "services/GenericSearchWorker.js",
+                "shared": true
             }
         ]
     }

platform/search/src/services/GenericSearchProvider.js

@@ -59,11 +59,9 @@ define([
         this.worker = this.startWorker(workerService);
         this.indexOnMutation(topic);
 
-        ROOTS.forEach(function indexRoot(rootId) {
-            provider.scheduleForIndexing(rootId);
-        });
-
+        this.rootsToIndex = ROOTS;
 
+        this.worker.port.postMessage({ request: 'status' });
     }
 
     /**
@@ -102,7 +100,8 @@ define([
         var worker = workerService.run('genericSearchWorker'),
             provider = this;
 
-        worker.addEventListener('message', function (messageEvent) {
+        worker.port.start();
+        worker.port.addEventListener('message', function (messageEvent) {
             provider.onWorkerMessage(messageEvent);
         });
 
@@ -150,9 +149,12 @@ define([
      * @private
      */
     GenericSearchProvider.prototype.keepIndexing = function () {
+        if (this.pendingRequests === 0 && this.idsToIndex.length === 0) {
+            this.worker.port.postMessage({ request: 'finish' });
+        }
+
         while (this.pendingRequests < this.MAX_CONCURRENT_REQUESTS &&
-            this.idsToIndex.length
-            ) {
+                this.idsToIndex.length) {
             this.beginIndexRequest();
         }
     };
@@ -168,7 +170,7 @@ define([
     GenericSearchProvider.prototype.index = function (id, model) {
         var provider = this;
 
-        this.worker.postMessage({
+        this.worker.port.postMessage({
             request: 'index',
             model: model,
             id: id
@@ -220,14 +222,25 @@ define([
      * @private
      */
     GenericSearchProvider.prototype.onWorkerMessage = function (event) {
+        var provider = this,
+            pendingQuery,
+            modelResults;
+
+        if (event.data.request === 'status' && !event.data.finished) {
+            this.rootsToIndex.forEach(function indexRoot(rootId) {
+                provider.scheduleForIndexing(rootId);
+            });
+            return;
+        }
+
         if (event.data.request !== 'search') {
             return;
         }
 
-        var pendingQuery = this.pendingQueries[event.data.queryId],
-            modelResults = {
-                total: event.data.total
-            };
+        pendingQuery = this.pendingQueries[event.data.queryId];
+        modelResults = {
+            total: event.data.total
+        };
 
         modelResults.hits = event.data.results.map(function (hit) {
             return {
@@ -265,7 +278,7 @@ define([
     ) {
         var queryId = this.makeQueryId();
 
-        this.worker.postMessage({
+        this.worker.port.postMessage({
             request: 'search',
             input: searchInput,
             maxResults: maxResults,

platform/search/src/services/GenericSearchWorker.js

@@ -30,7 +30,8 @@
     // An array of objects composed of domain object IDs and models
     // {id: domainObject's ID, model: domainObject's model}
     var indexedItems = [],
-        TERM_SPLITTER = /[ _\*]/;
+        TERM_SPLITTER = /[ _\*]/,
+        status = { request: 'status', finished: false };
 
     function indexItem(id, model) {
         var vector = {
@@ -118,7 +119,7 @@
                     match.matchCount += 100;
                 } else if (match.item.vector.lowerCaseName ===
                            query.inputLowerCase) {
-                   match.matchCount += 50;
+                    match.matchCount += 50;
                 }
                 return match;
             })
@@ -147,11 +148,19 @@
         return message;
     }
 
-    self.onmessage = function (event) {
-        if (event.data.request === 'index') {
-            indexItem(event.data.id, event.data.model);
-        } else if (event.data.request === 'search') {
-            self.postMessage(search(event.data));
-        }
+    self.onconnect = function (connectEvent) {
+        var port = connectEvent.ports[0];
+
+        port.onmessage = function (event) {
+            if (event.data.request === 'index') {
+                indexItem(event.data.id, event.data.model);
+            } else if (event.data.request === 'search') {
+                port.postMessage(search(event.data));
+            } else if (event.data.request === 'status') {
+                port.postMessage(status);
+            } else if (event.data.request === 'finish') {
+                status.finished = true;
+            }
+        };
     };
 }());