Rewrite local storage (#4583)

* Reimplementation of Local Storage provider

* Added tests

* Remove identifierService mocks from all test specs

* Do not persist identifiers in couch

* Constant rename

* Fix broken test

* Clean up mock window functions

* Updated copyright notice

* Fixed bug in in-memory search indexer

src/plugins/localStorage/LocalStorageObjectProvider.js

@@ -0,0 +1,100 @@
+/*****************************************************************************
+ * Open MCT, Copyright (c) 2014-2021, United States Government
+ * as represented by the Administrator of the National Aeronautics and Space
+ * Administration. All rights reserved.
+ *
+ * Open MCT is licensed under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * http://www.apache.org/licenses/LICENSE-2.0.
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ * Open MCT includes source code licensed under additional open source
+ * licenses. See the Open Source Licenses file (LICENSES.md) included with
+ * this source code distribution or the Licensing information page available
+ * at runtime from the About dialog for additional information.
+ *****************************************************************************/
+
+export default class LocalStorageObjectProvider {
+    constructor(spaceKey = 'mct') {
+        this.localStorage = window.localStorage;
+        this.spaceKey = spaceKey;
+        this.initializeSpace(spaceKey);
+    }
+
+    get(identifier) {
+        if (this.getSpaceAsObject()[identifier.key] !== undefined) {
+            const persistedModel = this.getSpaceAsObject()[identifier.key];
+            const domainObject = {
+                identifier,
+                ...persistedModel
+            };
+
+            return Promise.resolve(domainObject);
+        } else {
+            return Promise.resolve(undefined);
+        }
+    }
+
+    create(object) {
+        return this.persistObject(object);
+    }
+
+    update(object) {
+        return this.persistObject(object);
+    }
+
+    /**
+     * @private
+     */
+    persistObject(domainObject) {
+        let space = this.getSpaceAsObject();
+        space[domainObject.identifier.key] = domainObject;
+
+        this.persistSpace(space);
+
+        return Promise.resolve(true);
+    }
+
+    /**
+     * @private
+     */
+    persistSpace(space) {
+        this.localStorage[this.spaceKey] = JSON.stringify(space);
+    }
+
+    /**
+     * @private
+     */
+    getSpace() {
+        return this.localStorage[this.spaceKey];
+    }
+
+    /**
+     * @private
+     */
+    getSpaceAsObject() {
+        return JSON.parse(this.getSpace());
+    }
+
+    /**
+     * @private
+     */
+    initializeSpace() {
+        if (this.isEmpty()) {
+            this.localStorage[this.spaceKey] = JSON.stringify({});
+        }
+    }
+
+    /**
+     * @private
+     */
+    isEmpty() {
+        return this.getSpace() === undefined;
+    }
+}