Golang shim.ChaincodeStubInterface類代碼示例

// ============================================================================================================================
// findMarble4Trade - look for a matching marble that this user owns and return it
// ============================================================================================================================
func findMarble4Trade(stub shim.ChaincodeStubInterface, user string, color string, size int) (m Marble, err error) {
	var fail Marble
	fmt.Println("- start find marble 4 trade")
	fmt.Println("looking for " + user + ", " + color + ", " + strconv.Itoa(size))

	//get the marble index
	marblesAsBytes, err := stub.GetState(marbleIndexStr)
	if err != nil {
		return fail, errors.New("Failed to get marble index")
	}
	var marbleIndex []string
	json.Unmarshal(marblesAsBytes, &marbleIndex) //un stringify it aka JSON.parse()

	for i := range marbleIndex { //iter through all the marbles
		//fmt.Println("looking @ marble name: " + marbleIndex[i]);

		marbleAsBytes, err := stub.GetState(marbleIndex[i]) //grab this marble
		if err != nil {
			return fail, errors.New("Failed to get marble")
		}
		res := Marble{}
		json.Unmarshal(marbleAsBytes, &res) //un stringify it aka JSON.parse()
		//fmt.Println("looking @ " + res.User + ", " + res.Color + ", " + strconv.Itoa(res.Size));

		//check for user && color && size
		if strings.ToLower(res.User) == strings.ToLower(user) && strings.ToLower(res.Color) == strings.ToLower(color) && res.Size == size {
			fmt.Println("found a marble: " + res.Name)
			fmt.Println("! end find marble 4 trade")
			return res, nil
		}
	}

	fmt.Println("- end find marble 4 trade - error")
	return fail, errors.New("Did not find marble to use in this trade")
}

func (t *SimpleChaincode) query(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
	var event string // Event entity
	var err error

	if len(args) != 1 {
		return nil, errors.New("Incorrect number of arguments. Expecting entity to query")
	}

	event = args[0]

	// Get the state from the ledger
	eventValbytes, err := stub.GetState(event)
	if err != nil {
		jsonResp := "{\"Error\":\"Failed to get state for " + event + "\"}"
		return nil, errors.New(jsonResp)
	}

	if eventValbytes == nil {
		jsonResp := "{\"Error\":\"Nil value for " + event + "\"}"
		return nil, errors.New(jsonResp)
	}

	jsonResp := "{\"Name\":\"" + event + "\",\"Amount\":\"" + string(eventValbytes) + "\"}"
	fmt.Printf("Query Response:%s\n", jsonResp)
	return []byte(jsonResp), nil
}

func (t *AssetManagementChaincode) query(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
	var err error

	if len(args) != 1 {
		return nil, errors.New("Incorrect number of arguments. Expecting name of an asset to query")
	}

	// Who is the owner of the asset?
	asset := args[0]

	fmt.Printf("ASSET: %v", string(asset))

	var columns []shim.Column
	col1 := shim.Column{Value: &shim.Column_String_{String_: asset}}
	columns = append(columns, col1)

	row, err := stub.GetRow("AssetsOwnership", columns)
	if err != nil {
		jsonResp := "{\"Error\":\"Failed retrieving asset " + asset + ". Error " + err.Error() + ". \"}"
		return nil, errors.New(jsonResp)
	}

	if len(row.Columns) == 0 {
		jsonResp := "{\"Error\":\"Failed retrieving owner for " + asset + ". \"}"
		return nil, errors.New(jsonResp)
	}

	jsonResp := "{\"Owner\":\"" + string(row.Columns[1].GetBytes()) + "\"}"
	fmt.Printf("Query Response:%s\n", jsonResp)

	return row.Columns[1].GetBytes(), nil
}

func createTableFour(stub shim.ChaincodeStubInterface) error {
	var columnDefsTableFour []*shim.ColumnDefinition
	columnOneTableFourDef := shim.ColumnDefinition{Name: "colOneTableFour",
		Type: shim.ColumnDefinition_STRING, Key: true}
	columnDefsTableFour = append(columnDefsTableFour, &columnOneTableFourDef)
	return stub.CreateTable("tableFour", columnDefsTableFour)
}

func (t *SimpleChaincode) query(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
	var A string // Entity
	var Aval int // Asset holding
	var err error

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

	A = args[0]
	Aval, err = strconv.Atoi(args[1])
	if err != nil {
		return nil, errors.New("Expecting integer value for asset holding")
	}
	fmt.Printf("Aval = %d\n", Aval)

	// Write the state to the ledger - this put is illegal within Run
	err = stub.PutState(A, []byte(strconv.Itoa(Aval)))
	if err != nil {
		jsonResp := "{\"Error\":\"Cannot put state within chaincode query\"}"
		return nil, errors.New(jsonResp)
	}

	fmt.Printf("Something is wrong. This query should not have succeeded")
	return nil, 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 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
}

func createTableThree(stub shim.ChaincodeStubInterface) error {
	var columnDefsTableThree []*shim.ColumnDefinition
	columnOneTableThreeDef := shim.ColumnDefinition{Name: "colOneTableThree",
		Type: shim.ColumnDefinition_STRING, Key: true}
	columnTwoTableThreeDef := shim.ColumnDefinition{Name: "colTwoTableThree",
		Type: shim.ColumnDefinition_INT32, Key: false}
	columnThreeTableThreeDef := shim.ColumnDefinition{Name: "colThreeTableThree",
		Type: shim.ColumnDefinition_INT64, Key: false}
	columnFourTableThreeDef := shim.ColumnDefinition{Name: "colFourTableFour",
		Type: shim.ColumnDefinition_UINT32, Key: false}
	columnFiveTableThreeDef := shim.ColumnDefinition{Name: "colFourTableFive",
		Type: shim.ColumnDefinition_UINT64, Key: false}
	columnSixTableThreeDef := shim.ColumnDefinition{Name: "colFourTableSix",
		Type: shim.ColumnDefinition_BYTES, Key: false}
	columnSevenTableThreeDef := shim.ColumnDefinition{Name: "colFourTableSeven",
		Type: shim.ColumnDefinition_BOOL, Key: false}
	columnDefsTableThree = append(columnDefsTableThree, &columnOneTableThreeDef)
	columnDefsTableThree = append(columnDefsTableThree, &columnTwoTableThreeDef)
	columnDefsTableThree = append(columnDefsTableThree, &columnThreeTableThreeDef)
	columnDefsTableThree = append(columnDefsTableThree, &columnFourTableThreeDef)
	columnDefsTableThree = append(columnDefsTableThree, &columnFiveTableThreeDef)
	columnDefsTableThree = append(columnDefsTableThree, &columnSixTableThreeDef)
	columnDefsTableThree = append(columnDefsTableThree, &columnSevenTableThreeDef)
	return stub.CreateTable("tableThree", columnDefsTableThree)
}

// Query callback representing the query of a chaincode
func (t *Attributes2State) Query(stub shim.ChaincodeStubInterface, function string, args []string) ([]byte, error) {
	if function != "read" {
		return nil, errors.New("Invalid query function name. Expecting \"read\"")
	}
	var attributeName string // Name of the attributeName to query.
	var err error

	if len(args) != 1 {
		return nil, errors.New("Incorrect number of arguments. Expecting only 1 (attributeName)")
	}

	attributeName = args[0]
	fmt.Printf("Reading attribute %v", attributeName)

	// Get the state from the ledger
	Avalbytes, err := stub.GetState(attributeName)
	if err != nil {
		jsonResp := "{\"Error\":\"Failed to get state for " + attributeName + "\"}"
		fmt.Printf("Query Response:%s\n", jsonResp)
		return nil, errors.New(jsonResp)
	}

	if Avalbytes == nil {
		jsonResp := "{\"Error\":\"Nil amount for " + attributeName + "\"}"
		fmt.Printf("Query Response:%s\n", jsonResp)
		return nil, errors.New(jsonResp)
	}

	jsonResp := "{\"Name\":\"" + attributeName + "\",\"Amount\":\"" + string(Avalbytes) + "\"}"
	fmt.Printf("Query Response:%s\n", jsonResp)
	return []byte(jsonResp), nil
}

// Transaction makes payment of X units from A to B
func (t *ChaincodeExample) MakePayment(stub shim.ChaincodeStubInterface, param *example02.PaymentParams) error {

	var err error

	// Get the state from the ledger
	src, err := t.GetState(stub, param.PartySrc)
	if err != nil {
		return err
	}

	dst, err := t.GetState(stub, param.PartyDst)
	if err != nil {
		return err
	}

	// Perform the execution
	X := int(param.Amount)
	src = src - X
	dst = dst + X
	fmt.Printf("Aval = %d, Bval = %d\n", src, dst)

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

	err = stub.PutState(param.PartyDst, []byte(strconv.Itoa(dst)))
	if err != nil {
		return err
	}

	return nil
}

// ============================================================================================================================
// Set User Permission on Marble
// ============================================================================================================================
func (t *SimpleChaincode) set_user(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
	var err error

	//   0       1
	// "name", "bob"
	if len(args) < 2 {
		return nil, errors.New("Incorrect number of arguments. Expecting 2")
	}

	fmt.Println("- start set user")
	fmt.Println(args[0] + " - " + args[1])
	marbleAsBytes, err := stub.GetState(args[0])
	if err != nil {
		return nil, errors.New("Failed to get thing")
	}
	res := Marble{}
	json.Unmarshal(marbleAsBytes, &res) //un stringify it aka JSON.parse()
	res.User = args[1]                  //change the user

	jsonAsBytes, _ := json.Marshal(res)
	err = stub.PutState(args[0], jsonAsBytes) //rewrite the marble with id as key
	if err != nil {
		return nil, err
	}

	fmt.Println("- end set user")
	return nil, nil
}

func (t *SimpleChaincode) Init(stub shim.ChaincodeStubInterface, function string, args []string) ([]byte, error) {
	var A, B string    // Entities
	var Aval, Bval int // Asset holdings
	var err error

	if len(args) != 4 {
		return nil, errors.New("Incorrect number of arguments. Expecting 4")
	}

	// Initialize the chaincode
	A = args[0]
	Aval, err = strconv.Atoi(args[1])
	if err != nil {
		return nil, errors.New("Expecting integer value for asset holding")
	}
	B = args[2]
	Bval, err = strconv.Atoi(args[3])
	if err != nil {
		return nil, errors.New("Expecting integer value for asset holding")
	}
	fmt.Printf("Aval = %d, Bval = %d\n", Aval, Bval)

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

	err = stub.PutState(B, []byte(strconv.Itoa(Bval)))
	if err != nil {
		return nil, err
	}

	return nil, nil
}

//Init func will return error if function has string "error" anywhere
func (p *PassthruChaincode) Init(stub shim.ChaincodeStubInterface) ([]byte, error) {
	function, _ := stub.GetFunctionAndParameters()
	if strings.Index(function, "error") >= 0 {
		return nil, errors.New(function)
	}
	return []byte(function), nil
}

// Query callback representing the query of a chaincode
func (t *SimpleChaincode) Query(stub shim.ChaincodeStubInterface, function string, args []string) ([]byte, error) {
	if function != "query" {
		return nil, errors.New("Invalid query function name. Expecting \"query\"")
	}
	var A string // Entities
	var err error

	if len(args) != 1 {
		return nil, errors.New("Incorrect number of arguments. Expecting name of the person to query")
	}

	A = args[0]

	// Get the state from the ledger
	Avalbytes, err := stub.GetState(A)
	if err != nil {
		jsonResp := "{\"Error\":\"Failed to get state for " + A + "\"}"
		return nil, errors.New(jsonResp)
	}

	if Avalbytes == nil {
		jsonResp := "{\"Error\":\"Nil amount for " + A + "\"}"
		return nil, errors.New(jsonResp)
	}

	jsonResp := "{\"Name\":\"" + A + "\",\"Amount\":\"" + string(Avalbytes) + "\"}"
	fmt.Printf("Query Response:%s\n", jsonResp)
	return Avalbytes, nil
}

// Init takes two arguments, a string and int. The string will be a key with
// the int as a value.
func (t *SimpleChaincode) Init(stub shim.ChaincodeStubInterface) ([]byte, error) {
	var sum string // Sum of asset holdings across accounts. Initially 0
	var sumVal int // Sum of holdings
	var err error
	_, args := stub.GetFunctionAndParameters()
	if len(args) != 2 {
		return nil, errors.New("Incorrect number of arguments. Expecting 2")
	}

	// Initialize the chaincode
	sum = args[0]
	sumVal, err = strconv.Atoi(args[1])
	if err != nil {
		return nil, errors.New("Expecting integer value for sum")
	}
	fmt.Printf("sumVal = %d\n", sumVal)

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

	return nil, nil
}

// Invoke gets the supplied key and if it exists, updates the key with the newly
// supplied value.
func (t *SampleSysCC) Invoke(stub shim.ChaincodeStubInterface, function string, args []string) ([]byte, error) {
	var key, val string // Entities

	if len(args) != 2 {
		return nil, errors.New("need 2 args (key and a value)")
	}

	// Initialize the chaincode
	key = args[0]
	val = args[1]

	_, err := stub.GetState(key)
	if err != nil {
		jsonResp := "{\"Error\":\"Failed to get val for " + key + "\"}"
		return nil, errors.New(jsonResp)
	}

	// Write the state to the ledger
	err = stub.PutState(key, []byte(val))
	if err != nil {
		return nil, err
	}

	return nil, nil
}