Modify data-group with REST

Using node.js

router.get('/', function(req, res) {
  // First, verify that a userID has been supplied
  var GATsecret = '', GATqrurl = '';
    var GATuserid = req.query.userid;
    var GATlogin = req.query.loginurl;
  if ( GATuserid ) {
    // Fetch the googleAppsKey records array and check for matching userid
      var bipCmdList = '/sys/failover';
      bip.list(bipCmdList, function(err, cres) {
          console.log(cres);

          var bipCmdList = '/ltm/dataGroup/internal/~Common~google_auth_keys?$select=records';
          bip.list(bipCmdList, function (err, bres) {
              if (err) throw err;
              if (!bres.records) {
                  holdList = {records: []};
              }
              else {
                  holdList = bres;

              }
              for (var i in holdList.records) {
                  if (holdList.records[i].name == GATuserid) {
                      GATsecret = holdList.records[i].data;
                  }
              }
              if (GATsecret.length != secretLength) {
                  GATsecret = random32(secretLength);
                  var newEntry = {"name": GATuserid, "data": GATsecret};
                  holdList.records.push(newEntry);
                  var bipCmdAdd = '/ltm/dataGroup/internal/~Common~google_auth_keys';
                  bip.modify(bipCmdAdd, holdList, function (err, ares) {
                      if (err) {
                          console.log(err);
                          throw err;
                      }
                  });
              }
              // Build the QRcode link
              GATqrurl = getQRcode(GATuserid, GATdomain, GATsecret);
              // Set the variables to be passed to Jade for rendering
              res.render('index', {
                  title: 'ZeOmega Auth Secret',
                  showuserid: GATuserid,
                  showsecret: GATsecret,
                  showqr: GATqrurl,
                  nexturl: GATlogin
              });
          });
      });
  }

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