[ADF-4793] The filters don't work on community-edition [ Use local storage for community version ] (#4973)

* * Use local storage for community version.

* * Created a communityModule.

* * Updated unit tests the recent changes

* * Updated documents.

* * Modified process/task filters doc.

lib/process-services-cloud/src/lib/services/local-preference-cloud.service.ts

@@ -0,0 +1,105 @@
+/*!
+ * @license
+ * Copyright 2019 Alfresco Software, Ltd.
+ *
+ * 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.
+ */
+
+import { Injectable } from '@angular/core';
+import { PreferenceCloudServiceInterface } from './preference-cloud.interface';
+import { StorageService } from '@alfresco/adf-core';
+import { Observable, of } from 'rxjs';
+
+@Injectable()
+export class LocalPreferenceCloudService implements PreferenceCloudServiceInterface {
+
+  constructor(private storage: StorageService) { }
+
+    /**
+     * Gets local preferences
+     * @param appName Name of the target app
+     * @returns List of local preferences
+     */
+    getPreferences(appName: string, key: string): Observable<any> {
+        if (key || key === '') {
+            return of(this.prepareLocalPreferenceResponse(key));
+        }
+    }
+
+    /**
+     * Gets local preference.
+     * @param appName Name of the target app
+     * @param key Key of the target preference
+     * @returns Observable of local preference
+     */
+    getPreferenceByKey(appName: string, key: string): Observable<any> {
+        return of(JSON.parse(this.storage.getItem(key)) || []);
+    }
+
+    /**
+     * Creates local preference.
+     * @param appName Name of the target app
+     * @param key Key of the target preference
+     * @newPreference Details of new local preference
+     * @returns Observable of created local preferences
+     */
+    createPreference(appName: string, key: string, newPreference: any): Observable<any> {
+        const storedFilters = JSON.parse(this.storage.getItem(key) || '[]');
+        storedFilters.push(...newPreference);
+        this.storage.setItem(key, JSON.stringify(storedFilters));
+        return of(storedFilters);
+    }
+
+    /**
+     * Updates local preference.
+     * @param appName Name of the target app
+     * @param key Key of the target preference
+     * @param updatedPreference Details of updated preference
+     * @returns Observable of updated local preferences
+     */
+    updatePreference(appName: string, key: string, updatedPreference: any): Observable<any> {
+        if (key) {
+            this.storage.setItem(key, JSON.stringify(updatedPreference));
+            return of(updatedPreference);
+        }
+    }
+
+    /**
+     * Deletes local preference by given preference key.
+     * @param appName Name of the target app
+     * @param key Key of the target preference
+     * @param preferences Details of updated preferences
+     * @returns Observable of preferences without deleted preference
+     */
+    deletePreference(key: string, preferences: any): Observable<any> {
+        if (key) {
+            this.storage.setItem(key, JSON.stringify(preferences));
+            return of(preferences);
+        }
+    }
+
+    prepareLocalPreferenceResponse(key: string): any {
+        return {
+            'list': {
+                'entries': [
+                    {
+                        'entry': {
+                            'key': key,
+                            'value': this.storage.getItem(key) || '[]'
+                        }
+                    }
+                ]
+            }
+        };
+    }
+}