chaincode_example03.go

/*
Licensed to the Apache Software Foundation (ASF) under one
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distributed with this work for additional information
regarding copyright ownership.  The ASF licenses this file
to you 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 (
	"errors"
	"fmt"
	"strconv"

	"github.com/openblockchain/obc-peer/openchain/chaincode/shim"
)

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

func (t *SimpleChaincode) init(stub *shim.ChaincodeStub, 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")
	}

	// 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")
	}
	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 nil, err
	}

	return nil, nil
}

// Run callback representing the invocation of a chaincode
func (t *SimpleChaincode) Run(stub *shim.ChaincodeStub, function string, args []string) ([]byte, error) {

	// Handle different functions
	if function == "init" {
		// Initialize
		return t.init(stub, args)
	}

	return nil, nil
}

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

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