Chore: Adding find bar metrics (#835)

src/lib/events.js

@@ -68,3 +68,9 @@ export const DOWNLOAD_REACHABILITY_METRICS = {
     NOTIFICATION_SHOWN: 'dl_reachability_notification_shown',
     DOWNLOAD_BLOCKED: 'dl_reachability_host_blocked'
 };
+// Events fired when using find in preview
+export const USER_DOCUMENT_FIND_EVENTS = {
+    NEXT: 'user_document_find_next', // The user navigates to the next find entry
+    OPEN: 'user_document_find_open', // The user opens the find bar
+    PREVIOUS: 'user_document_find_previous' // The user navigates to the previous find entry
+};

src/lib/viewers/doc/DocBaseViewer.js

@@ -74,6 +74,7 @@ class DocBaseViewer extends BaseViewer {
         this.pinchToZoomStartHandler = this.pinchToZoomStartHandler.bind(this);
         this.pinchToZoomChangeHandler = this.pinchToZoomChangeHandler.bind(this);
         this.pinchToZoomEndHandler = this.pinchToZoomEndHandler.bind(this);
+        this.emitMetric = this.emitMetric.bind(this);
     }
 
     /**
@@ -132,6 +133,7 @@ class DocBaseViewer extends BaseViewer {
         // Clean up the find bar
         if (this.findBar) {
             this.findBar.destroy();
+            this.findBar.removeListener(VIEWER_EVENT.metric, this.emitMetric);
         }
 
         // Clean up PDF network requests
@@ -317,6 +319,7 @@ class DocBaseViewer extends BaseViewer {
             return;
         }
         this.findBar = new DocFindBar(this.findBarEl, this.findController, canDownload);
+        this.findBar.addListener(VIEWER_EVENT.metric, this.emitMetric);
     }
 
     /**
@@ -527,6 +530,18 @@ class DocBaseViewer extends BaseViewer {
         return true;
     }
 
+    /**
+     * Emits a viewer metric. Useful for unpacking a message that comes from another class.
+     *
+     * @protected
+     * @emits metric
+     * @param {Object} event - Event object
+     * @return {void}
+     */
+    emitMetric(event) {
+        super.emitMetric(event.name, event.data);
+    }
+
     //--------------------------------------------------------------------------
     // Protected
     //--------------------------------------------------------------------------

src/lib/viewers/doc/DocFindBar.js

@@ -1,5 +1,6 @@
 import EventEmitter from 'events';
 import { decodeKeydown } from '../../util';
+import { USER_DOCUMENT_FIND_EVENTS, VIEWER_EVENT } from '../../events';
 import { CLASS_HIDDEN } from '../../constants';
 import { ICON_FIND_DROP_DOWN, ICON_FIND_DROP_UP, ICON_CLOSE, ICON_SEARCH } from '../../icons/icons';
 
@@ -328,6 +329,11 @@ class DocFindBar extends EventEmitter {
                     this.currentMatch = 1;
                 }
             }
+
+            // Emit a metric that the user navigated forward in the find bar
+            this.emit(VIEWER_EVENT.metric, {
+                name: USER_DOCUMENT_FIND_EVENTS.NEXT
+            });
         }
     }
 
@@ -351,6 +357,11 @@ class DocFindBar extends EventEmitter {
                     this.currentMatch = this.findController.matchCount;
                 }
             }
+
+            // Emit a metric that the user navigated back in the find bar
+            this.emit(VIEWER_EVENT.metric, {
+                name: USER_DOCUMENT_FIND_EVENTS.PREVIOUS
+            });
         }
     }
 
@@ -370,6 +381,10 @@ class DocFindBar extends EventEmitter {
         if (!this.opened) {
             this.opened = true;
             this.bar.classList.remove(CLASS_HIDDEN);
+            // Emit a metric that the user opened the find bar
+            this.emit(VIEWER_EVENT.metric, {
+                name: USER_DOCUMENT_FIND_EVENTS.OPEN
+            });
         }
         this.findFieldEl.select();
         this.findFieldEl.focus();

src/lib/viewers/doc/__tests__/DocBaseViewer-test.js

@@ -123,11 +123,13 @@ describe('src/lib/viewers/doc/DocBaseViewer', () => {
 
         it('should destroy the find bar', () => {
             docBase.findBar = {
-                destroy: sandbox.stub()
+                destroy: sandbox.stub(),
+                removeListener: sandbox.stub()
             };
 
             docBase.destroy();
             expect(docBase.findBar.destroy).to.be.called;
+            expect(docBase.findBar.removeListener).to.be.called;
         });
 
         it('should clean up the PDF network requests', () => {
@@ -481,7 +483,8 @@ describe('src/lib/viewers/doc/DocBaseViewer', () => {
                 setFindFieldElValue: sandbox.stub(),
                 findFieldHandler: sandbox.stub(),
                 open: sandbox.stub(),
-                destroy: sandbox.stub()
+                destroy: sandbox.stub(),
+                removeListener: sandbox.stub()
             };
 
             sandbox.stub(docBase, 'setPage');
@@ -791,7 +794,8 @@ describe('src/lib/viewers/doc/DocBaseViewer', () => {
             const onKeydownStub = sandbox.stub().withArgs(mockEvent);
             docBase.findBar = {
                 onKeydown: onKeydownStub,
-                destroy: sandbox.stub()
+                destroy: sandbox.stub(),
+                removeListener: sandbox.stub()
             };
             docBase.onKeydown(keys, mockEvent);
             expect(onKeydownStub).to.have.been.calledOnce;

src/lib/viewers/doc/__tests__/DocFindBar-test.js

@@ -2,6 +2,7 @@
 import DocFindBar from '../DocFindBar';
 import { CLASS_HIDDEN } from '../../../constants';
 import * as util from '../../../util';
+import { VIEWER_EVENT, USER_DOCUMENT_FIND_EVENTS } from '../../../events';
 
 const CLASS_FIND_MATCH_NOT_FOUND = 'bp-find-match-not-found';
 
@@ -233,7 +234,7 @@ describe('lib/viewers/doc/DocFindBar', () => {
         it('should set the findFieldEl value', () => {
             docFindBar.findFieldEl = {
                 removeEventListener: sandbox.stub()
-            }
+            };
 
             docFindBar.setFindFieldElValue('test');
 
@@ -479,6 +480,18 @@ describe('lib/viewers/doc/DocFindBar', () => {
             docFindBar.findNextHandler(true);
             expect(docFindBar.currentMatch).to.equal(1);
         });
+
+        it('should emit the find next event', () => {
+            sandbox.stub(docFindBar, 'emit');
+            docFindBar.findFieldEl.value = 'test';
+            docFindBar.findController.matchCount = 1;
+            docFindBar.currentMatch = 2;
+
+            docFindBar.findNextHandler(true);
+            expect(docFindBar.emit).to.be.calledWith(VIEWER_EVENT.metric, {
+                name: USER_DOCUMENT_FIND_EVENTS.NEXT
+            });
+        });
     });
 
     describe('findPreviousHandler()', () => {
@@ -517,6 +530,17 @@ describe('lib/viewers/doc/DocFindBar', () => {
             docFindBar.findPreviousHandler(true);
             expect(docFindBar.currentMatch).to.equal(5);
         });
+
+        it('should emit a find previous metric', () => {
+            sandbox.stub(docFindBar, 'emit');
+            docFindBar.findFieldEl.value = 'test';
+            docFindBar.currentMatch = 0;
+
+            docFindBar.findPreviousHandler(true);
+            expect(docFindBar.emit).to.be.calledWith(VIEWER_EVENT.metric, {
+                name: USER_DOCUMENT_FIND_EVENTS.PREVIOUS
+            });
+        });
     });
     describe('open()', () => {
         beforeEach(() => {
@@ -542,11 +566,15 @@ describe('lib/viewers/doc/DocFindBar', () => {
         });
 
         it('should open the find bar if it is not open', () => {
+            sandbox.stub(docFindBar, 'emit');
             docFindBar.opened = false;
 
             docFindBar.open();
             expect(docFindBar.opened).to.equal(true);
             expect(stubs.remove).to.be.called;
+            expect(docFindBar.emit).to.be.calledWith(VIEWER_EVENT.metric, {
+                name: USER_DOCUMENT_FIND_EVENTS.OPEN
+            });
         });
 
         it('should not open the find bar if it is already open', () => {