code: function(chain) {
      const retryAttempts = 100
        , timerInterval = 5000
        , chainTimer = {timer: undefined, blockNumber: 0, retryCounter: 0}
        , provider = (chain == 'utility' ? web3UtilityProvider : web3ValueProvider)
      ;
      return new Promise(function (onResolve, onReject) {
        chainTimer['timer'] = setInterval(function () {
          if (chainTimer['retryCounter'] <= retryAttempts) {
            provider.eth.getBlockNumber(function (err, blocknumber) {
              if (err) {
              } else {
                if (chainTimer['blockNumber']!=0 && chainTimer['blockNumber']!=blocknumber) {
                  logger.info("* Geth Checker - " + chain + " chain has new blocks.");
                  clearInterval(chainTimer['timer']);
                  onResolve();
                }
                chainTimer['blockNumber'] = blocknumber;
              }
            });
          } else {
            logger.error("Geth Checker - " + chain + " chain has no new blocks.");
            onReject();
            process.exit(1);
          }
          chainTimer['retryCounter']++;
        }, timerInterval);
      });
    }
docs: Check if mentioned chain started mining and are ready
  
  @param {string} chain - name of the chain
  
  @return {promise}