Jixie Bid Adapter: add schain (prebid#8439)

* Adapter does not seem capable of supporting advertiserDomains prebid#6650
added response comment and some trivial code.

* removed a blank line at the end of file
added a space behind the // in comments

* in response to comment from reviewer. add the aspect of advertiserdomain in unit tests

* added the code to get the keywords from the meta tags if available.

* jixie sending schain info to jixie backend

* support of schain info sent to jixie endpoint, fixing some indentation complaints from auto build check

modules/jixieBidAdapter.js

@@ -184,6 +184,7 @@ export const spec = {
     let ids = fetchIds_();
     let eids = [];
     let miscDims = internal.getMiscDims();
+    let schain = deepAccess(validBidRequests[0], 'schain');
 
     // all available user ids are sent to our backend in the standard array layout:
     if (validBidRequests[0].userId) {
@@ -209,6 +210,7 @@ export const spec = {
       mkeywords: miscDims.mkeywords,
       bids: bids,
       eids: eids,
+      schain: schain,
       pricegranularity: pg,
       cfg: jixieCfgBlob
     }, ids);

test/spec/modules/jixieBidAdapter_spec.js

@@ -285,6 +285,23 @@ describe('jixie Adapter', function () {
       expect(payload.device).to.deep.include(content);
     });
 
+    it('schain info should be accessible when available', function () {
+      const schain = {
+        ver: '1.0',
+        complete: 1,
+        nodes: [{
+          asi: 'ssp.test',
+          sid: '00001',
+          hp: 1
+        }]
+      };
+      const oneSpecialBidReq = Object.assign({}, bidRequests_[0], { schain: schain });
+      const request = spec.buildRequests([oneSpecialBidReq], bidderRequest_);
+      const payload = JSON.parse(request.data);
+      expect(payload.schain).to.deep.equal(schain);
+      expect(payload.schain).to.deep.include(schain);
+    });
+
     it('should populate eids when supported userIds are available', function () {
       const oneSpecialBidReq = Object.assign({}, bidRequests_[0], {
         userId: {