prebid · patmmccann · Dec 15, 2022 · Sep 5, 2022 · Sep 5, 2022 · Sep 6, 2022
diff --git a/integrationExamples/gpt/topics_frame.html b/integrationExamples/gpt/topics_frame.html
@@ -0,0 +1,43 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <title>Topics demo</title>
+    <meta charset="utf-8">
+    <meta http-equiv="X-UA-Compatible" content="IE=edge">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <link href="favicon.ico" rel="shortcut icon">
+    <script>
+      async function getTopics() {
+        try {
+          if ('browsingTopics' in document && document.featurePolicy.allowsFeature('browsing-topics')) {
+            const topics = await document.browsingTopics();
+            console.log('Called iframe:', window.location.hostname, topics, '\nNumber of topics: ', topics.length);
+            return Promise.resolve(topics);
+          } else {
+            console.log('document.browsingTopics() not supported');
+          }
+
+        } catch (error) {
+          console.log('Error:', error);
+        }
+      }
+
+      document.addEventListener('DOMContentLoaded', async function () {
+        const topics = await getTopics()
+        const url = new URL(window.location.href);
+        const params = new URLSearchParams(url.search);
+        const message = JSON.stringify({
+          segment: {
+            domain: window.location.hostname,
+            topics,
+            bidder: params.get("bidder")
+          },
+          date: Date.now(),
+        });
+        window.parent.postMessage(message, '*');
+      });
+    </script>
+  </head>
+  <body>
+  </body>
+</html>
diff --git a/modules/topicsFpdModule.js b/modules/topicsFpdModule.js
@@ -1,8 +1,31 @@
-import {logError, logWarn, mergeDeep} from '../src/utils.js';
+import {logError, logWarn, mergeDeep, isEmpty, safeJSONParse, logInfo, hasDeviceAccess} from '../src/utils.js';
 import {getRefererInfo} from '../src/refererDetection.js';
 import {submodule} from '../src/hook.js';
 import {GreedyPromise} from '../src/utils/promise.js';
+import {config} from '../src/config.js';
+import {getCoreStorageManager} from '../src/storageManager.js';
+import {includes} from '../src/polyfill.js';
+import {gdprDataHandler} from '../src/adapterManager.js';
 
+const MODULE_NAME = 'topicsFpd';
+const DEFAULT_EXPIRATION_DAYS = 21;
+const TCF_REQUIRED_PURPOSES = ['1', '2', '3', '4'];
+let HAS_GDPR_CONSENT = true;
+let LOAD_TOPICS_INITIALISE = false;
+const HAS_DEVICE_ACCESS = hasDeviceAccess();
+
+const bidderIframeList = {
+  maxTopicCaller: 1,
+  bidders: [{
+    bidder: 'pubmatic',
+    iframeURL: 'https://ads.pubmatic.com/AdServer/js/topics/topics_frame.html'
+  }]
+}
+export const coreStorage = getCoreStorageManager(MODULE_NAME);
+export const topicStorageName = 'prebid:topics';
+export const lastUpdated = 'lastUpdated';
+
+const iframeLoadedURL = [];
 const TAXONOMIES = {
   // map from topic taxonomyVersion to IAB segment taxonomy
   '1': 600
@@ -17,6 +40,20 @@ function partitionBy(field, items) {
   }, {});
 }
 
+/**
+ * function to get list of loaded Iframes calling Topics API
+ */
+function getLoadedIframeURL() {
+  return iframeLoadedURL;
+}
+
+/**
+ * function to set/push iframe in the list which is loaded to called topics API.
+ */
+function setLoadedIframeURL(url) {
+  return iframeLoadedURL.push(url);
+}
+
 export function getTopicsData(name, topics, taxonomies = TAXONOMIES) {
   return Object.entries(partitionBy('taxonomyVersion', topics))
     .filter(([taxonomyVersion]) => {
@@ -61,7 +98,12 @@ export function getTopics(doc = document) {
 const topicsData = getTopics().then((topics) => getTopicsData(getRefererInfo().domain, topics));
 
 export function processFpd(config, {global}, {data = topicsData} = {}) {
+  if (!LOAD_TOPICS_INITIALISE) {
+    loadTopicsForBidders();
+    LOAD_TOPICS_INITIALISE = true;
+  }
   return data.then((data) => {
+    data = [].concat(data, getCachedTopics()); // Add cached data in FPD data.
     if (data.length) {
       mergeDeep(global, {
         user: {
@@ -73,6 +115,145 @@ export function processFpd(config, {global}, {data = topicsData} = {}) {
   });
 }
 
+/**
+ * function to fetch the cached topic data from storage for bidders and return it
+ */
+function getCachedTopics() {
+  let cachedTopicData = [];
+  if (!HAS_GDPR_CONSENT && !HAS_DEVICE_ACCESS) {
+    return cachedTopicData;
+  }
+  const topics = config.getConfig('userSync.topics') || bidderIframeList;
+  const bidderList = topics.bidders || [];
+  let storedSegments = new Map(safeJSONParse(coreStorage.getDataFromLocalStorage(topicStorageName)));
+  storedSegments && storedSegments.forEach((value, cachedBidder) => {
+    // Check bidder exist in config for cached bidder data and then only retrieve the cached data
+    let isBidderConfigured = bidderList.some(({bidder}) => cachedBidder == bidder)
+    if (isBidderConfigured) {
+      if (!isCachedDataExpired(value[lastUpdated], isBidderConfigured?.expiry || DEFAULT_EXPIRATION_DAYS)) {
+        Object.keys(value).forEach((segData) => {
+          value != lastUpdated && cachedTopicData.push(value[segData]);
+        })
+      } else {
+        // delete the specific bidder map from the store and store the updated maps
+        storedSegments.delete(cachedBidder);
+        coreStorage.setDataInLocalStorage(topicStorageName, JSON.stringify([...storedSegments]));
+      }
+    }
+  });
+  return cachedTopicData;
+}
+
+/**
+ * Recieve messages from iframe loaded for bidders to fetch topic
+ * @param {MessageEvent} evt
+ */
+function receiveMessage(evt) {
+  if (evt && evt.data) {
+    try {
+      let data = safeJSONParse(evt.data);
+      if (includes(getLoadedIframeURL(), evt.origin) && data && data.segment && !isEmpty(data.segment.topics)) {
+        const {domain, topics, bidder} = data.segment;
+        const iframeTopicsData = getTopicsData(domain, topics)[0];
+        iframeTopicsData && storeInLocalStorage(bidder, iframeTopicsData);
+      }
+    } catch (err) { }
+  }
+}
+
+/**
+Function to store Topics data recieved from iframe in storage(name: "prebid:topics")
+* @param {Topics} topics
+*/
+export function storeInLocalStorage(bidder, topics) {
+  const storedSegments = new Map(safeJSONParse(coreStorage.getDataFromLocalStorage(topicStorageName)));
+  if (storedSegments.has(bidder)) {
+    storedSegments.get(bidder)[topics['ext']['segclass']] = topics;
+    storedSegments.get(bidder)[lastUpdated] = new Date().getTime();
+    storedSegments.set(bidder, storedSegments.get(bidder));
+  } else {
+    storedSegments.set(bidder, {[topics.ext.segclass]: topics, [lastUpdated]: new Date().getTime()})
+  }
+  coreStorage.setDataInLocalStorage(topicStorageName, JSON.stringify([...storedSegments]));
+}
+
+function isCachedDataExpired(storedTime, cacheTime) {
+  const _MS_PER_DAY = 1000 * 60 * 60 * 24;
+  const now = new Date().getTime();
+  const daysDifference = Math.floor((storedTime - now) / _MS_PER_DAY);
+  return daysDifference > cacheTime;
+}
+
+/**
+* Function to get random bidders based on count passed with array of bidders
+**/
+function getRandomBidders(arr, count) {
+  return ([...arr].sort(() => 0.5 - Math.random())).slice(0, count)
+}
+
+/**
+ * function to add listener for message receiving from IFRAME
+ */
+function listenMessagesFromTopicIframe() {
+  window.addEventListener('message', receiveMessage, false);
+}
+
+function checkTCFv2(vendorData, requiredPurposes = TCF_REQUIRED_PURPOSES) {
+  const {gdprApplies, purpose} = vendorData;
+  if (!gdprApplies) {
+    return true;
+  }
+  return requiredPurposes.map((purposeNo) => {
+    const purposeConsent = purpose.consents ? purpose.consents[purposeNo] : false;
+    if (purposeConsent) {
+      return true;
+    }
+    return false;
+  }).reduce((a, b) => a && b, true);
+}
+
+function hasGDPRConsent() {
+  // Check for GDPR consent for purpose 1,2,3,4 and return false if consent has not been given
+  const gdprConsent = gdprDataHandler.getConsentData();
+  const hasGdpr = (gdprConsent && typeof gdprConsent.gdprApplies === 'boolean' && gdprConsent.gdprApplies) ? 1 : 0;
+  const gdprConsentString = hasGdpr ? gdprConsent.consentString : '';
+  if (hasGdpr) {
+    if ((!gdprConsentString || gdprConsentString === '') || !gdprConsent.vendorData) {
+      return false;
+    }
+    return checkTCFv2(gdprConsent.vendorData);
+  }
+  return true;
+}
+
+/**
+ * function to load the iframes of the bidder to load the topics data
+ */
+function loadTopicsForBidders() {
+  HAS_GDPR_CONSENT = hasGDPRConsent();
+  if (!HAS_GDPR_CONSENT && !HAS_DEVICE_ACCESS) {
+    logInfo('Topics Module : Consent string is required to fetch the topics from third party domains.');
+    return;
+  }
+  const topics = config.getConfig('userSync.topics') || bidderIframeList;
+  if (topics) {
+    listenMessagesFromTopicIframe();
+    const randomBidders = getRandomBidders(topics.bidders || [], topics.maxTopicCaller || 1)
+    randomBidders && randomBidders.forEach(({ bidder, iframeURL }) => {
+      if (bidder && iframeURL) {
+        let ifrm = document.createElement('iframe');
+        ifrm.name = 'ifrm_'.concat(bidder);
+        ifrm.src = ''.concat(iframeURL, '?bidder=').concat(bidder);
+        ifrm.style.display = 'none';
+        setLoadedIframeURL(new URL(iframeURL).origin);
+        iframeURL && window.document.documentElement.appendChild(ifrm);
+      }
+    })
+  } else {
+    logWarn(`Topics config not defined under userSync Object`);
+  }
+}
+
 submodule('firstPartyData', {
   name: 'topics',
   queue: 1,