PBjs Core : add ability to inject tracking in video

src/auction.js

@@ -83,7 +83,7 @@ import {config} from './config.js';
 import {userSync} from './userSync.js';
 import {hook} from './hook.js';
 import {find, includes} from './polyfill.js';
-import {OUTSTREAM} from './video.js';
+import {OUTSTREAM, getVastTrackers, insertVastTrackers} from './video.js';
 import {VIDEO} from './mediaTypes.js';
 import {auctionManager} from './auctionManager.js';
 import {bidderSettings} from './bidderSettings.js';
@@ -582,7 +582,11 @@ function tryAddVideoBid(auctionInstance, bidResponse, afterBidAdded, {index = au
     }), 'video');
   const context = videoMediaType && deepAccess(videoMediaType, 'context');
   const useCacheKey = videoMediaType && deepAccess(videoMediaType, 'useCacheKey');
+  const vastTrackers = getVastTrackers(bidResponse);
 
+  if (vastTrackers) {
+    bidResponse.vastXml = insertVastTrackers(vastTrackers, bidResponse.vastXml);
+  }
   if (config.getConfig('cache.url') && (useCacheKey || context !== OUTSTREAM)) {
     if (!bidResponse.videoCacheKey || config.getConfig('cache.ignoreBidderCacheKey')) {
       addBid = false;

src/video.js

@@ -4,6 +4,9 @@ import { config } from '../src/config.js';
 import {includes} from './polyfill.js';
 import { hook } from './hook.js';
 import {auctionManager} from './auctionManager.js';
+import {isActivityAllowed} from './activities/rules.js';
+import {activityParams} from './activities/activityParams.js';
+import {ACTIVITY_REPORT_ANALYTICS} from './activities/activities.js';
 
 const VIDEO_MEDIA_TYPE = 'video';
 export const OUTSTREAM = 'outstream';
@@ -21,6 +24,8 @@ export const videoBidder = bid => includes(adapterManager.videoAdapters, bid.bid
 export const hasNonVideoBidder = adUnit =>
   adUnit.bids.filter(bid => !videoBidder(bid)).length;
 
+let vastTrackers = [];
+
 /**
  * @typedef {object} VideoBid
  * @property {string} adId id of the bid
@@ -64,3 +69,66 @@ export const checkVideoBidSetup = hook('sync', function(bid, adUnit, videoMediaT
 
   return true;
 }, 'checkVideoBidSetup');
+
+export function registerVastTrackers(moduleType, moduleName, trackerFn) {
+  if (typeof trackerFn === 'function') {
+    vastTrackers.push({'moduleType': moduleType, 'moduleName': moduleName, 'trackerFn': trackerFn});
+  }
+}
+
+export function insertVastTrackers(trackers, vastXml) {
+  const doc = new DOMParser().parseFromString(vastXml, 'text/xml');
+  const wrappers = doc.querySelectorAll('VAST Ad Wrapper, VAST Ad InLine');
+  try {
+    if (wrappers.length) {
+      wrappers.forEach(wrapper => {
+        if (trackers.get('impressions')) {
+          trackers.get('impressions').forEach(trackingUrl => {
+            const impression = doc.createElement('Impression');
+            impression.appendChild(doc.createCDATASection(trackingUrl));
+            wrapper.appendChild(impression)
+          });
+        }
+      });
+      vastXml = new XMLSerializer().serializeToString(doc);
+    }
+  } catch (error) {
+    logError('an error happened trying to insert trackers in vastXml');
+  }
+  return vastXml;
+}
+
+export function getVastTrackers(bid) {
+  let trackers = [];
+  vastTrackers.filter(
+    ({moduleType, moduleName, trackerFn}) => isActivityAllowed(ACTIVITY_REPORT_ANALYTICS, activityParams(moduleType, moduleName))
+  ).forEach(({trackerFn}) => {
+    let trackersToAdd = trackerFn(bid);
+    trackersToAdd.forEach(trackerToAdd => {
+      if (isValidVastTracker(trackers, trackerToAdd)) { trackers.push(trackerToAdd); }
+    });
+  });
+  const trackersMap = trackersToMap(trackers);
+  return (trackersMap.size ? trackersMap : null);
+};
+
+function isValidVastTracker(trackers, trackerToAdd) {
+  return trackerToAdd.hasOwnProperty('event') && trackerToAdd.hasOwnProperty('url');
+}
+
+function trackersToMap(trackers) {
+  return trackers.reduce((map, {url, event}) => {
+    !map.has(event) && map.set(event, new Set())
+    map.get(event).add(url);
+    return map;
+  }, new Map())
+}
+
+export function addImpUrlToTrackers(bid, trackersMap) {
+  if (bid.vastImpUrl) {
+    if (!trackersMap) { trackersMap = new Map(); }
+    if (!trackersMap.get('impressions')) { trackersMap.set('impressions', new Set()); }
+    trackersMap.get('impressions').add(bid.vastImpUrl);
+  }
+  return trackersMap;
+}

src/videoCache.js

@@ -12,6 +12,7 @@
 import {ajaxBuilder} from './ajax.js';
 import {config} from './config.js';
 import {auctionManager} from './auctionManager.js';
+import {getVastTrackers, addImpUrlToTrackers} from './video.js';
 
 /**
  * Might be useful to be configurable in the future
@@ -42,17 +43,22 @@ const ttlBufferInSeconds = 15;
  * @param {string} impUrl An impression tracker URL for the delivery of the video ad
  * @return A VAST URL which loads XML from the given URI.
  */
-function wrapURI(uri, impUrl) {
+function wrapURI(uri, vastTrackers) {
   // Technically, this is vulnerable to cross-script injection by sketchy vastUrl bids.
   // We could make sure it's a valid URI... but since we're loading VAST XML from the
   // URL they provide anyway, that's probably not a big deal.
-  let vastImp = (impUrl) ? `<![CDATA[${impUrl}]]>` : ``;
+  let impressions = '';
+  if (vastTrackers && vastTrackers.get('impressions')) {
+    vastTrackers.get('impressions').forEach(trackingImp => {
+      impressions += `<Impression><![CDATA[${trackingImp}]]></Impression>`;
+    });
+  }
   return `<VAST version="3.0">
     <Ad>
       <Wrapper>
         <AdSystem>prebid.org wrapper</AdSystem>
         <VASTAdTagURI><![CDATA[${uri}]]></VASTAdTagURI>
-        <Impression>${vastImp}</Impression>
+        ${impressions}
         <Creatives></Creatives>
       </Wrapper>
     </Ad>
@@ -67,7 +73,7 @@ function wrapURI(uri, impUrl) {
  * @param index
  */
 function toStorageRequest(bid, {index = auctionManager.index} = {}) {
-  const vastValue = bid.vastXml ? bid.vastXml : wrapURI(bid.vastUrl, bid.vastImpUrl);
+  const vastValue = bid.vastXml ? bid.vastXml : wrapURI(bid.vastUrl, addImpUrlToTrackers(bid, getVastTrackers(bid)));
   const auction = index.getAuction(bid);
   const ttlWithBuffer = Number(bid.ttl) + ttlBufferInSeconds;
   let payload = {

test/spec/videoCache_spec.js

@@ -1,10 +1,12 @@
 import chai from 'chai';
+import { registerVastTrackers } from 'src/video.js';
 import { getCacheUrl, store } from 'src/videoCache.js';
 import { config } from 'src/config.js';
 import { server } from 'test/mocks/xhr.js';
 import {auctionManager} from '../../src/auctionManager.js';
 import {AuctionIndex} from '../../src/auctionIndex.js';
 import { batchingCache } from '../../src/auction.js';
+import { MODULE_TYPE_ANALYTICS } from 'src/activities/modules.js';
 
 const should = chai.should();
 
@@ -127,7 +129,7 @@ describe('The video cache', function () {
       <Wrapper>
         <AdSystem>prebid.org wrapper</AdSystem>
         <VASTAdTagURI><![CDATA[my-mock-url.com]]></VASTAdTagURI>
-        <Impression></Impression>
+
         <Creatives></Creatives>
       </Wrapper>
     </Ad>
@@ -149,6 +151,39 @@ describe('The video cache', function () {
       assertRequestMade({ vastUrl: 'my-mock-url.com', vastImpUrl: 'imptracker.com', ttl: 25 }, expectedValue)
     });
 
+    it('should include additional impressions trackers on top of vastImpUrl when they exist', function() {
+      registerVastTrackers(MODULE_TYPE_ANALYTICS, 'test', function(bidResponse) {
+        return [
+	  {'event': 'impressions', 'url': `https://vasttracking.mydomain.com/vast?cpm=${bidResponse.cpm}`}
+        ];
+      });
+      const expectedValue = `<VAST version="3.0">
+    <Ad>
+      <Wrapper>
+        <AdSystem>prebid.org wrapper</AdSystem>
+        <VASTAdTagURI><![CDATA[my-mock-url.com]]></VASTAdTagURI>
+        <Impression><![CDATA[https://vasttracking.mydomain.com/vast?cpm=1.2]]></Impression><Impression><![CDATA[imptracker.com]]></Impression>
+        <Creatives></Creatives>
+      </Wrapper>
+    </Ad>
+  </VAST>`;
+      assertRequestMade({ vastUrl: 'my-mock-url.com', vastImpUrl: 'imptracker.com', ttl: 25, cpm: 1.2 }, expectedValue)
+    });
+
+    it('should include only additional impressions trackers when they exist', function() {
+      const expectedValue = `<VAST version="3.0">
+    <Ad>
+      <Wrapper>
+        <AdSystem>prebid.org wrapper</AdSystem>
+        <VASTAdTagURI><![CDATA[my-mock-url.com]]></VASTAdTagURI>
+        <Impression><![CDATA[https://vasttracking.mydomain.com/vast?cpm=1.2]]></Impression>
+        <Creatives></Creatives>
+      </Wrapper>
+    </Ad>
+  </VAST>`;
+      assertRequestMade({ vastUrl: 'my-mock-url.com', ttl: 25, cpm: 1.2 }, expectedValue)
+    });
+
     it('should make the expected request when store() is called on an ad with vastXml', function () {
       const vastXml = '<VAST version="3.0"></VAST>';
       assertRequestMade({ vastXml: vastXml, ttl: 25 }, vastXml);

test/spec/video_spec.js

@@ -1,6 +1,7 @@
-import { isValidVideoBid } from 'src/video.js';
+import { isValidVideoBid, registerVastTrackers, insertVastTrackers, getVastTrackers, addImpUrlToTrackers } from 'src/video.js';
 import {hook} from '../../src/hook.js';
 import {stubAuctionIndex} from '../helpers/indexStub.js';
+import { MODULE_TYPE_ANALYTICS } from 'src/activities/modules.js';
 
 describe('video.js', function () {
   before(() => {
@@ -100,4 +101,33 @@ describe('video.js', function () {
     const valid = isValidVideoBid(bid, {index: stubAuctionIndex({adUnits})});
     expect(valid).to.equal(false);
   });
+
+  it('insert into tracker list', function() {
+    let trackers = getVastTrackers({'cpm': 1.0});
+    if (!trackers || !trackers.get('impressions')) {
+      registerVastTrackers(MODULE_TYPE_ANALYTICS, 'test', function(bidResponse) {
+        return [
+          {'event': 'impressions', 'url': `https://vasttracking.mydomain.com/vast?cpm=${bidResponse.cpm}`}
+        ];
+      });
+    }
+    trackers = getVastTrackers({'cpm': 1.0});
+    expect(trackers).to.be.a('map');
+    expect(trackers.get('impressions')).to.exists;
+    expect(trackers.get('impressions').has('https://vasttracking.mydomain.com/vast?cpm=1')).to.be.true;
+  });
+
+  it('insert trackers in vastXml', function() {
+    const trackers = getVastTrackers({'cpm': 1.0});
+    let vastXml = '<VAST><Ad><Wrapper></Wrapper></Ad></VAST>';
+    vastXml = insertVastTrackers(trackers, vastXml);
+    expect(vastXml).to.equal('<VAST><Ad><Wrapper><Impression><![CDATA[https://vasttracking.mydomain.com/vast?cpm=1]]></Impression></Wrapper></Ad></VAST>');
+  });
+
+  it('test addImpUrlToTrackers', function() {
+    const trackers = addImpUrlToTrackers({'vastImpUrl': 'imptracker.com'}, getVastTrackers({'cpm': 1.0}));
+    expect(trackers).to.be.a('map');
+    expect(trackers.get('impressions')).to.exists;
+    expect(trackers.get('impressions').has('imptracker.com')).to.be.true;
+  });
 });