add meta key to interpreted bid response (#5358)

* add meta key to interpreted bid response

* add more unit tests

Co-authored-by: sumit sharma <sumit.sharma1@SYNPUNLT9114TFL.appnexus.com>
Co-authored-by: sumit sharma <sumit.sharma1@SYNPUNLT9114TFL.SYNAPPNXS.local>

src/adapters/bidderFactory.js

@@ -307,6 +307,7 @@ export function newBidder(spec) {
               // creating a copy of original values as cpm and currency are modified later
               bid.originalCpm = bid.cpm;
               bid.originalCurrency = bid.currency;
+              bid.meta = bid.meta || Object.assign({}, bid[bidRequest.bidder]);
               const prebidBid = Object.assign(createBid(CONSTANTS.STATUS.GOOD, bidRequest), bid);
               addBidWithCode(bidRequest.adUnitCode, prebidBid);
             } else {

test/spec/unit/core/bidderFactory_spec.js

@@ -401,8 +401,12 @@ describe('bidders created by newBidder', function () {
         adUnitCode: 'mock/placement',
         currency: 'USD',
         netRevenue: true,
-        ttl: 300
+        ttl: 300,
+        bidderCode: 'sampleBidder',
+        sampleBidder: {advertiserId: '12345', networkId: '111222'}
       };
+      const bidderRequest = Object.assign({}, MOCK_BIDS_REQUEST);
+      bidderRequest.bids[0].bidder = 'sampleBidder';
       spec.isBidRequestValid.returns(true);
       spec.buildRequests.returns({
         method: 'POST',
@@ -413,7 +417,7 @@ describe('bidders created by newBidder', function () {
 
       spec.interpretResponse.returns(bid);
 
-      bidder.callBids(MOCK_BIDS_REQUEST, addBidResponseStub, doneStub, ajaxStub, onTimelyResponseStub, wrappedCallback);
+      bidder.callBids(bidderRequest, addBidResponseStub, doneStub, ajaxStub, onTimelyResponseStub, wrappedCallback);
 
       expect(addBidResponseStub.calledOnce).to.equal(true);
       expect(addBidResponseStub.firstCall.args[0]).to.equal('mock/placement');
@@ -423,6 +427,8 @@ describe('bidders created by newBidder', function () {
       expect(bidObject.originalCurrency).to.equal(bid.currency);
       expect(doneStub.calledOnce).to.equal(true);
       expect(logErrorSpy.callCount).to.equal(0);
+      expect(bidObject.meta).to.exist;
+      expect(bidObject.meta).to.deep.equal({advertiserId: '12345', networkId: '111222'});
     });
 
     it('should call spec.getUserSyncs() with the response', function () {