Refactor clone/copy of a database.

Author: Viatorus

packages/loki/src/collection.ts

@@ -305,6 +305,16 @@ export class Collection<TData extends object = object, TNested extends object =
     this.flushChanges();
   }
 
+  public copy(): Collection<TData, TNested> {
+    const collCopy = clone(this, "shallow");
+     collCopy._dynamicViews = [];
+
+    for (let i = 0; i < this._dynamicViews.length; i++) {
+       collCopy._dynamicViews[i] = this._dynamicViews[i].copy();
+    }
+    return  collCopy;
+  }
+
   toJSON(): Collection.Serialized {
     return {
       name: this.name,
@@ -330,11 +340,8 @@ export class Collection<TData extends object = object, TNested extends object =
     };
   }
 
-  static fromJSONObject(obj: Collection | Collection.Serialized, options?: Collection.DeserializeOptions) {
-    if (obj instanceof Collection) {
-      return clone(this, "shallow");
-    }
 
+  static fromJSONObject(obj: Collection.Serialized, options?: Collection.DeserializeOptions) {
     let coll = new Collection<any>(obj.name, {
       disableChangesApi: obj.disableChangesApi,
       disableDeltaChangesApi: obj.disableDeltaChangesApi

packages/loki/src/dynamic_view.ts

@@ -3,6 +3,7 @@ import {ResultSet} from "./result_set";
 import {Collection} from "./collection";
 import {Doc} from "../../common/types";
 import {Scorer} from "../../full-text-search/src/scorer";
+import {clone} from "./clone";
 
 /**
  * DynamicView class is a versatile 'live' view class which can have filters and sorts applied.
@@ -147,6 +148,10 @@ export class DynamicView<TData extends object = object, TNested extends object =
     return rs.transform(transform, parameters);
   }
 
+  public copy(): DynamicView<TData, TNested> {
+    return clone(this, "shallow");
+  }
+
   /**
    * Override of toJSON to avoid circular references.
    */

packages/loki/src/loki.ts

@@ -1,6 +1,7 @@
 /* global global */
 import {LokiEventEmitter} from "./event_emitter";
 import {Collection} from "./collection";
+import {clone} from "./clone";
 import {Doc, StorageAdapter} from "../../common/types";
 import {PLUGINS} from "../../common/plugin";
 
@@ -191,26 +192,21 @@ export class Loki extends LokiEventEmitter {
    * @param {boolean} options.removeNonSerializable - nulls properties not safe for serialization.
    */
   public copy(options: Loki.CopyOptions = {}): Loki {
-    const databaseCopy = new Loki(this.filename, {env: this._env});
+    const dbCopy = clone(this, "shallow");
+    dbCopy._collections = [];
 
-    // currently inverting and letting loadJSONObject do most of the work
-    databaseCopy.loadJSONObject(this, {
-      retainDirtyFlags: true
-    });
+    for (let i = 0; i < this._collections.length; i++) {
+      dbCopy._collections[i] = this._collections[i].copy();
+    }
 
-    // since our toJSON is not invoked for reference database adapters, this will let us mimic
     if (options.removeNonSerializable) {
-      // databaseCopy._autosaveHandle = null;
-      // databaseCopy._persistenceAdapter = null;
-
-      for (let idx = 0; idx < databaseCopy._collections.length; idx++) {
-        // TODO: Move to class.
-        // databaseCopy._collections[idx]._constraints = null;
-        // databaseCopy._collections[idx]._ttl = null;
-      }
+      dbCopy._autosaveHandler = Promise.resolve();
+      dbCopy._persistenceAdapter = null;
+      dbCopy._throttledSaveRunning = null;
+      dbCopy._throttledSavePending = null;
     }
 
-    return databaseCopy;
+    return dbCopy;
   }
 
   /**
@@ -341,7 +337,7 @@ export class Loki extends LokiEventEmitter {
       _serializationMethod: this._serializationMethod,
       _autosave: this._autosave,
       _autosaveInterval: this._autosaveInterval,
-      _collections: this._collections,
+      _collections: this._collections as any as Collection.Serialized[],
       databaseVersion: this.databaseVersion,
       engineVersion: this.engineVersion,
       filename: this.filename,
@@ -388,8 +384,9 @@ export class Loki extends LokiEventEmitter {
     }
 
     // not just an individual collection, so we will need to serialize db container via shallow copy
-    let dbcopy = new Loki(this.filename);
-    dbcopy.loadJSONObject(this);
+    // let dbcopy = new Loki(this.filename);
+    // dbcopy.loadJSONObject(this);
+    let dbcopy = this.copy();
 
     for (let idx = 0; idx < dbcopy._collections.length; idx++) {
       dbcopy._collections[idx]._data = [];
@@ -680,13 +677,11 @@ export class Loki extends LokiEventEmitter {
 
   /**
    * Inflates a loki database from a JS object
-   *
    * @param {object} dbObject - a serialized loki database object
    * @param {object} options - apply or override collection level settings
    * @param {boolean} options.retainDirtyFlags - whether collection dirty flags will be preserved
    */
-  // public loadJSONObject(dbObject: Loki, options?: Collection.DeserializeOptions): void;
-  public loadJSONObject(dbObject: Loki | Loki.Serialized, options: Collection.DeserializeOptions = {}): void {
+  public loadJSONObject(dbObject: Loki.Serialized, options: Collection.DeserializeOptions = {}): void {
     // Legacy support.
     // if (dbObject.databaseVersion === 1.5) {
     //   dbObject = dbObject as LokiJS.Loki;
@@ -1084,7 +1079,7 @@ export namespace Loki {
     _serializationMethod: SerializationMethod;
     _autosave: boolean;
     _autosaveInterval: number;
-    _collections: Collection[];
+    _collections: Collection.Serialized[];
     databaseVersion: 2.0;
     engineVersion: 2.0;
     filename: string;