Add method for requesting full drawing history

Author: Peshou

README.md

@@ -384,6 +384,8 @@ export class AppComponent {
   }
 }   
 ```
+### Requesting the full update history so far
+Can be called via the method  `getDrawingHistory(): CanvasWhiteboardUpdate[]`. The items will be deep cloned for consistency using lodash.
 
 ## Saving drawn canvas as an image
 In order to save drawn images you can either click the Save button in the canvas, 

dist/canvas-whiteboard.component.d.ts

@@ -405,6 +405,12 @@ export declare class CanvasWhiteboardComponent implements OnInit, AfterViewInit,
      */
     toggleShapeSelector(value: boolean): void;
     selectShape(newShapeBlueprint: INewCanvasWhiteboardShape<CanvasWhiteboardShape>): void;
+    /**
+     * Returns a deep copy of the current drawing history for the canvas.
+     * The deep copy is returned because we don't want anyone to mutate the current history
+     * @returns {CanvasWhiteboardUpdate[]}
+     */
+    getDrawingHistory(): CanvasWhiteboardUpdate[];
     /**
      * Unsubscribe from a given subscription if it is active
      * @param {Subscription} subscription

dist/canvas-whiteboard.component.js

@@ -1,6 +1,6 @@
 {
   "name": "ng2-canvas-whiteboard",
-  "version": "2.1.1",
+  "version": "2.1.2",
   "description": "A Canvas component for Angular which supports free drawing.",
   "main": "index.js",
   "scripts": {
@@ -38,7 +38,9 @@
     "custom shapes",
     "custom premade shapes"
   ],
-  "dependencies": {},
+  "dependencies": {
+    "lodash.clonedeep": "4.5.0"
+  },
   "peerDependencies": {
     "rxjs-compat": "^6.0.0"
   },
@@ -47,6 +49,7 @@
     "@angular/compiler-cli": "4.3.2",
     "@angular/compiler": "4.3.2",
     "@angular/core": "4.3.2",
+    "@types/lodash": "^4.14.116",
     "typescript": "2.2.1",
     "rxjs": "5.2.0",
     "rxjs-compat": "^6.0.0",

dist/canvas-whiteboard.component.metadata.json

@@ -18,6 +18,7 @@ import {CanvasWhiteboardPoint} from "./canvas-whiteboard-point";
 import {CanvasWhiteboardShapeService, INewCanvasWhiteboardShape} from "./shapes/canvas-whiteboard-shape.service";
 import {Observable} from "rxjs";
 import {CanvasWhiteboardShapeOptions} from "./shapes/canvas-whiteboard-shape-options";
+import * as cloneDeep from "lodash.cloneDeep";
 
 @Component({
     selector: 'canvas-whiteboard',
@@ -825,7 +826,7 @@ export class CanvasWhiteboardComponent implements OnInit, AfterViewInit, OnChang
      * @return Emits an Array of Updates when the batch.
      */
     private _prepareUpdateForBatchDispatch(update: CanvasWhiteboardUpdate): void {
-        this._batchUpdates.push(update);
+        this._batchUpdates.push(cloneDeep(update));
         if (!this._updateTimeout) {
             this._updateTimeout = setTimeout(() => {
                 this.onBatchUpdate.emit(this._batchUpdates);
@@ -1081,6 +1082,15 @@ export class CanvasWhiteboardComponent implements OnInit, AfterViewInit, OnChang
         this.selectedShapeConstructor = newShapeBlueprint;
     }
 
+    /**
+     * Returns a deep copy of the current drawing history for the canvas.
+     * The deep copy is returned because we don't want anyone to mutate the current history
+     * @returns {CanvasWhiteboardUpdate[]}
+     */
+    getDrawingHistory(): CanvasWhiteboardUpdate[] {
+        return cloneDeep(this._updateHistory);
+    }
+
     /**
      * Unsubscribe from a given subscription if it is active
      * @param {Subscription} subscription