addressed feedback and created tests

libraries/previousAuctionInfo/previousAuctionInfo.js

@@ -0,0 +1,130 @@
+import {on as onEvent} from '../../src/events.js';
+import { EVENTS } from '../../src/constants.js';
+
+export let previousAuctionInfoEnabled = false;
+let enabledBidders = [];
+export let winningBidsMap = {};
+
+export const resetPreviousAuctionInfo = () => {
+  previousAuctionInfoEnabled = false;
+  enabledBidders = [];
+  winningBidsMap = {};
+};
+
+export const enablePreviousAuctionInfo = (config, cb = initHandlers) => {
+  const { bidderCode, isBidRequestValid } = config;
+  const enabledBidder = enabledBidders.find(bidder => bidder.bidderCode === bidderCode);
+  if (!enabledBidder) enabledBidders.push({ bidderCode, isBidRequestValid, maxQueueLength: config.maxQueueLength || 10 });
+  if (previousAuctionInfoEnabled) return;
+  previousAuctionInfoEnabled = true;
+  cb();
+}
+
+export const initHandlers = () => {
+  onEvent(EVENTS.AUCTION_END, onAuctionEndHandler);
+  onEvent(EVENTS.BID_WON, onBidWonHandler);
+  onEvent(EVENTS.BID_REQUESTED, onBidRequestedHandler);
+};
+
+export const onAuctionEndHandler = (auctionDetails) => {
+  // eslint-disable-next-line no-console
+  console.log('onAuctionEndHandler', auctionDetails);
+
+  try {
+    let highestCpmBid = 0;
+    const receivedBidsMap = {};
+    const rejectedBidsMap = {};
+
+    if (auctionDetails.bidsReceived && auctionDetails.bidsReceived.length) {
+      highestCpmBid = auctionDetails.bidsReceived.reduce((highestBid, currentBid) => {
+        return currentBid.cpm > highestBid.cpm ? currentBid : highestBid;
+      }, auctionDetails.bidsReceived[0]);
+
+      auctionDetails.bidsReceived.forEach(bidReceived => {
+        receivedBidsMap[bidReceived.requestId] = bidReceived;
+      });
+    }
+
+    if (auctionDetails.bidsRejected && auctionDetails.bidsRejected.length) {
+      auctionDetails.bidsRejected.forEach(bidRejected => {
+        rejectedBidsMap[bidRejected.requestId] = bidRejected;
+      });
+    }
+
+    if (auctionDetails.bidderRequests && auctionDetails.bidderRequests.length) {
+      auctionDetails.bidderRequests.forEach(bidderRequest => {
+        const enabledBidder = enabledBidders.find(bidder => bidder.bidderCode === bidderRequest.bidderCode);
+
+        if (enabledBidder) {
+          bidderRequest.bids.forEach(bid => {
+            const isValidBid = enabledBidder.isBidRequestValid(bid);
+
+            if (!isValidBid) return;
+
+            const previousAuctionInfoPayload = {
+              bidderRequestId: bidderRequest.bidderRequestId,
+              minBidToWin: highestCpmBid?.cpm || 0,
+              rendered: 0,
+              transactionId: bid.ortb2Imp.ext.tid || bid.transactionId,
+              source: 'pbjs',
+              auctionId: auctionDetails.auctionId,
+              impId: bid.adUnitCode,
+              // bidResponseId: FLOAT, // don't think this is available client side?
+              // targetedbidcpm: FLOAT, // don't think this is available client side?
+              highestcpm: highestCpmBid?.cpm || 0,
+              cur: bid.ortb2.cur,
+              bidderCpm: receivedBidsMap[bid.bidId] ? receivedBidsMap[bid.bidId].cpm : 'nobid',
+              biddererrorcode: rejectedBidsMap[bid.bidId] ? rejectedBidsMap[bid.bidId].rejectionReason : -1,
+              timestamp: auctionDetails.timestamp,
+            }
+
+            window.pbpai = window.pbpai || {};
+            if (!window.pbpai[bidderRequest.bidderCode]) {
+              window.pbpai[bidderRequest.bidderCode] = [];
+            }
+
+            if (window.pbpai[bidderRequest.bidderCode].length > enabledBidder.maxQueueLength) {
+              window.pbpai[bidderRequest.bidderCode].shift();
+            }
+
+            window.pbpai[bidderRequest.bidderCode].push(previousAuctionInfoPayload);
+          });
+        }
+      });
+    }
+  } catch (error) {
+    // eslint-disable-next-line no-console
+    console.error(error);
+  }
+}
+
+const onBidWonHandler = (winningBid) => {
+  // // eslint-disable-next-line no-console
+  // console.log('onBidWonHandler', winningBid);
+  winningBidsMap[winningBid.transactionId] = winningBid;
+}
+
+export const onBidRequestedHandler = (bidRequest) => {
+  try {
+    const enabledBidder = enabledBidders.find(bidder => bidder.bidderCode === bidRequest.bidderCode);
+    window.pbpai = window.pbpai || {};
+
+    if (enabledBidder && window.pbpai[bidRequest.bidderCode]) {
+      window.pbpai[bidRequest.bidderCode].forEach(prevAuctPayload => {
+        if (winningBidsMap[prevAuctPayload.transactionId]) {
+          prevAuctPayload.minBidToWin = winningBidsMap[prevAuctPayload.transactionId].cpm;
+          prevAuctPayload.rendered = 1;
+        }
+      });
+
+      bidRequest.ortb2 ??= {};
+      bidRequest.ortb2.ext ??= {};
+      bidRequest.ortb2.ext.prebid ??= {};
+      bidRequest.ortb2.ext.prebid.previousauctioninfo = window.pbpai[bidRequest.bidderCode];
+      delete window.pbpai[bidRequest.bidderCode];
+    }
+  } catch (error) {
+    // eslint-disable-next-line no-console
+    console.error(error);
+  }
+}

test/spec/libraries/previousAuctionInfo_spec.js

@@ -0,0 +1,81 @@
+import * as previousAuctionInfo from 'libraries/previousAuctionInfo/previousAuctionInfo.js';
+import sinon from 'sinon';
+
+describe('previous auction info', () => {
+  let sandbox;
+  let initHandlersStub;
+
+  const auctionDetails = {
+    auctionId: 'auction123',
+    bidsReceived: [{ requestId: 'bid1', bidderCode: 'testBidder2', cpm: 2 }],
+    bidsRejected: [{ requestId: 'bid2', rejectionReason: 1 }],
+    bidderRequests: [
+      {
+        bidderCode: 'testBidder2',
+        bidderRequestId: 'req1',
+        bids: [{ bidId: 'bid1', ortb2: { cur: ['US'] }, ortb2Imp: { ext: { tid: 'trans123' } }, adUnitCode: 'adUnit1' }],
+      },
+    ],
+    timestamp: Date.now(),
+  };
+
+  beforeEach(() => {
+    previousAuctionInfo.resetPreviousAuctionInfo();
+    if (window.pbpai) delete window.pbpai;
+    sandbox = sinon.createSandbox();
+    initHandlersStub = sandbox.stub();
+  });
+
+  afterEach(() => {
+    sandbox.restore();
+    if (window.pbpai) delete window.pbpai;
+  });
+
+  describe('config', () => {
+    it('should only be initialized once', () => {
+      const config = { bidderCode: 'testBidder', isBidRequestValid: () => true };
+      previousAuctionInfo.enablePreviousAuctionInfo(config, initHandlersStub);
+      sandbox.assert.calledOnce(initHandlersStub);
+      previousAuctionInfo.enablePreviousAuctionInfo(config, initHandlersStub);
+      sandbox.assert.calledOnce(initHandlersStub);
+    });
+  });
+
+  describe('on auction end', () => {
+    it('should only capture data for enabled bids who submitted a valid bid', () => {
+      const config = { bidderCode: 'testBidder2', isBidRequestValid: (bid) => bid.bidId === 'bid1' };
+      previousAuctionInfo.enablePreviousAuctionInfo(config, initHandlersStub);
+      previousAuctionInfo.onAuctionEndHandler(auctionDetails);
+
+      expect(window.pbpai.testBidder2).to.be.an('array').with.lengthOf(1);
+      expect(window.pbpai.testBidder2[0]).to.include({
+        auctionId: 'auction123',
+        minBidToWin: 2,
+        transactionId: 'trans123',
+        rendered: 0,
+      });
+    });
+  });
+
+  describe('on bid requested', () => {
+    it('should update the minBidToWin and rendered fields if a pbjs bid wins', () => {
+      const config = { bidderCode: 'testBidder3', isBidRequestValid: () => true };
+      previousAuctionInfo.enablePreviousAuctionInfo(config, initHandlersStub);
+      const bidRequest = {
+        bidderCode: 'testBidder3',
+        ortb2: { ext: { prebid: {} } },
+      };
+
+      previousAuctionInfo.winningBidsMap['trans123'] = { cpm: 5, transactionId: 'trans123' };
+
+      window.pbpai = {
+        testBidder3: [{ transactionId: 'trans123', minBidToWin: 0, rendered: 0 }],
+      };
+
+      previousAuctionInfo.onBidRequestedHandler(bidRequest);
+      const updatedInfo = bidRequest.ortb2.ext.prebid.previousauctioninfo;
+      expect(updatedInfo).to.be.an('array').with.lengthOf(1);
+      expect(updatedInfo[0]).to.include({ minBidToWin: 5, rendered: 1 });
+    });
+  });
+});