chaincode_example03.go

/*
Copyright IBM Corp. 2016 All Rights Reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

		 http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

// This program is an erroneous chaincode program that attempts to put state in query context - query should return error
package main

import (
	"fmt"
	"strconv"

	"github.com/hyperledger/fabric/core/chaincode/shim"
	pb "github.com/hyperledger/fabric/protos/peer"
)

// SimpleChaincode example simple Chaincode implementation
type SimpleChaincode struct {
}

// Init takes a string and int. These are stored as a key/value pair in the state
func (t *SimpleChaincode) Init(stub shim.ChaincodeStubInterface) pb.Response {
	var A string // Entity
	var Aval int // Asset holding
	var err error
	_, args := stub.GetFunctionAndParameters()
	if len(args) != 2 {
		return shim.Error("Incorrect number of arguments. Expecting 2")
	}

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

	// Write the state to the ledger - this put is legal within Run
	err = stub.PutState(A, []byte(strconv.Itoa(Aval)))
	if err != nil {
		return shim.Error(err.Error())
	}

	return shim.Success(nil)
}

// Invoke is a no-op
func (t *SimpleChaincode) Invoke(stub shim.ChaincodeStubInterface) pb.Response {
	function, args := stub.GetFunctionAndParameters()
	if function == "query" {
		return t.query(stub, args)
	}

	return shim.Error("Invalid invoke function name. Expecting \"query\"")
}

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

	if len(args) != 2 {
		return shim.Error("Incorrect number of arguments. Expecting 2")
	}

	A = args[0]
	Aval, err = strconv.Atoi(args[1])
	if err != nil {
		return shim.Error("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 shim.Error(jsonResp)
	}

	return shim.Success(nil)
}

func main() {
	err := shim.Start(new(SimpleChaincode))
	if err != nil {
		fmt.Printf("Error starting chaincode: %s", err)
	}
}