Golang ChaincodeStubInterface.InvokeChaincode方法代碼示例

// Invoke invokes another chaincode - chaincode_example02, upon receipt of an event and changes event state
func (t *SimpleChaincode) Invoke(stub shim.ChaincodeStubInterface, function string, args []string) ([]byte, error) {
	var event string    // Event entity
	var eventVal string // State of event
	var err error
	var amount int

	event = args[0]
	eventVal = args[1]
	chainCodeToCall := args[2] // Get the chaincode to call from the ledger

	if eventVal == "middleSchool" {
		amount = 2000
	} else {
		amount = 5000
	}

	// 轉賬操作
	invokeArgs := util.ToChaincodeArgs("transferAcc", args[3], args[4], strconv.Itoa(amount))
	response, err := stub.InvokeChaincode(chainCodeToCall, invokeArgs)
	if err != nil {
		errStr := fmt.Sprintf("Failed to invoke chaincode. Got error: %s", err.Error())
		fmt.Printf(errStr)
		return nil, errors.New(errStr)
	}

	fmt.Printf("Invoke chaincode successful. Got response %s", string(response))

	// Write the event state back to the ledger
	err = stub.PutState(event, []byte(args[1]))
	if err != nil {
		return nil, err
	}

	return nil, nil
}

//helper
func (p *PassthruChaincode) iq(stub shim.ChaincodeStubInterface, function string, args []string) ([]byte, error) {
	if function == "" {
		return nil, errors.New("Chaincode ID not provided")
	}
	chaincodeID := function

	return stub.InvokeChaincode(chaincodeID, util.ToChaincodeArgs(args...))
}

// Invoke queries another chaincode and updates its own state
func (t *SimpleChaincode) invoke(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
	var sum string             // Sum entity
	var Aval, Bval, sumVal int // value of sum entity - to be computed
	var err error

	if len(args) != 2 {
		return nil, errors.New("Incorrect number of arguments. Expecting 2")
	}

	chaincodeURL := args[0] // Expecting "github.com/hyperledger/fabric/core/example/chaincode/chaincode_example02"
	sum = args[1]

	// Query chaincode_example02
	f := "query"
	queryArgs := util.ToChaincodeArgs(f, "a")
	response, err := stub.InvokeChaincode(chaincodeURL, queryArgs)
	if err != nil {
		errStr := fmt.Sprintf("Failed to query chaincode. Got error: %s", err.Error())
		fmt.Printf(errStr)
		return nil, errors.New(errStr)
	}
	Aval, err = strconv.Atoi(string(response))
	if err != nil {
		errStr := fmt.Sprintf("Error retrieving state from ledger for queried chaincode: %s", err.Error())
		fmt.Printf(errStr)
		return nil, errors.New(errStr)
	}

	queryArgs = util.ToChaincodeArgs(f, "b")
	response, err = stub.InvokeChaincode(chaincodeURL, queryArgs)
	if err != nil {
		errStr := fmt.Sprintf("Failed to query chaincode. Got error: %s", err.Error())
		fmt.Printf(errStr)
		return nil, errors.New(errStr)
	}
	Bval, err = strconv.Atoi(string(response))
	if err != nil {
		errStr := fmt.Sprintf("Error retrieving state from ledger for queried chaincode: %s", err.Error())
		fmt.Printf(errStr)
		return nil, errors.New(errStr)
	}

	// Compute sum
	sumVal = Aval + Bval

	// Write sumVal back to the ledger
	err = stub.PutState(sum, []byte(strconv.Itoa(sumVal)))
	if err != nil {
		return nil, err
	}

	fmt.Printf("Invoke chaincode successful. Got sum %d\n", sumVal)
	return []byte(strconv.Itoa(sumVal)), nil
}

func (t *SimpleChaincode) query(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
	var sum string             // Sum entity
	var Aval, Bval, sumVal int // value of sum entity - to be computed
	var err error

	if len(args) != 2 {
		return nil, errors.New("Incorrect number of arguments. Expecting 2")
	}

	chaincodeURL := args[0]
	sum = args[1]

	// Query chaincode_example02
	f := "query"
	queryArgs := util.ToChaincodeArgs(f, "a")
	response, err := stub.InvokeChaincode(chaincodeURL, queryArgs)
	if err != nil {
		errStr := fmt.Sprintf("Failed to query chaincode. Got error: %s", err.Error())
		fmt.Printf(errStr)
		return nil, errors.New(errStr)
	}
	Aval, err = strconv.Atoi(string(response))
	if err != nil {
		errStr := fmt.Sprintf("Error retrieving state from ledger for queried chaincode: %s", err.Error())
		fmt.Printf(errStr)
		return nil, errors.New(errStr)
	}

	queryArgs = util.ToChaincodeArgs(f, "b")
	response, err = stub.InvokeChaincode(chaincodeURL, queryArgs)
	if err != nil {
		errStr := fmt.Sprintf("Failed to query chaincode. Got error: %s", err.Error())
		fmt.Printf(errStr)
		return nil, errors.New(errStr)
	}
	Bval, err = strconv.Atoi(string(response))
	if err != nil {
		errStr := fmt.Sprintf("Error retrieving state from ledger for queried chaincode: %s", err.Error())
		fmt.Printf(errStr)
		return nil, errors.New(errStr)
	}

	// Compute sum
	sumVal = Aval + Bval

	fmt.Printf("Query chaincode successful. Got sum %d\n", sumVal)
	jsonResp := "{\"Name\":\"" + sum + "\",\"Value\":\"" + strconv.Itoa(sumVal) + "\"}"
	fmt.Printf("Query Response:%s\n", jsonResp)
	return []byte(strconv.Itoa(sumVal)), nil
}

// Invoke invokes another chaincode - chaincode_example02, upon receipt of an event and changes event state
func (t *SimpleChaincode) Invoke(stub shim.ChaincodeStubInterface, function string, args []string) ([]byte, error) {
	var event string // Event entity
	var eventVal int // State of event
	var err error

	if len(args) != 2 {
		return nil, errors.New("Incorrect number of arguments. Expecting 2")
	}

	event = args[0]
	eventVal, err = strconv.Atoi(args[1])
	if err != nil {
		return nil, errors.New("Expected integer value for event state change")
	}

	if eventVal != 1 {
		fmt.Printf("Unexpected event. Doing nothing\n")
		return nil, nil
	}

	// Get the chaincode to call from the ledger
	chainCodeToCall := t.GetChaincodeToCall()

	f := "invoke"
	invokeArgs := util.ToChaincodeArgs(f, "a", "b", "10")
	response, err := stub.InvokeChaincode(chainCodeToCall, invokeArgs)
	if err != nil {
		errStr := fmt.Sprintf("Failed to invoke chaincode. Got error: %s", err.Error())
		fmt.Printf(errStr)
		return nil, errors.New(errStr)
	}

	fmt.Printf("Invoke chaincode successful. Got response %s", string(response))

	// Write the event state back to the ledger
	err = stub.PutState(event, []byte(strconv.Itoa(eventVal)))
	if err != nil {
		return nil, err
	}

	return nil, nil
}