// 2ndChaincode.go
func init() {
	if os.Getenv("DEV_CHANNEL_NAME") != "" { // dev mode
		ContractCfg.CC = "my-cc-contract"
	} else {
		ContractCfg.CC = "my-contract"
	}
}

func CreateContract(stub shim.ChaincodeStubInterface, doc []byte, expiry int64, signers *stringset.Set) (*Contract, error) {
	if nil == signers || signers.Size() < 2 {
		return nil, errors.New("signers must be 2+")
	}
	expb := []byte(strconv.FormatInt(expiry, 10))
	args := [][]byte{[]byte("create"), doc, expb} 
	for signer := range signers.Map() {
		args = append(args, []byte(signer))
	}
	// invoke
	res := stub.InvokeChaincode(ContractCfg.CC, args, "")
	if res.GetStatus() == 200 {
		payload := res.GetPayload()
		m := make(map[string]interface{})
		err := json.Unmarshal(payload, &m)
		if err != nil {
			return nil, err
		}
		contract := &Contract{_payload: payload, _map: m}
		return contract, nil
	}
	return nil, errors.New(res.GetMessage())
}