详解区块链Hyperledger Fabric资产（车辆）交易
首先定义Chaincode 链码及API， 通过定义相应的数据结构和方法就完成了一个智能契约，参考原文如下：
Chaincode is a program, written in Go, and eventually in other programming languages such as Java, that implements a prescribed interface. Chaincode runs in a secured Docker container isolated from the endorsing peer process. Chaincode initializes and manages ledger state through transactions submitted by applications. A chaincode typically handles business logic agreed to by members of the network, so it may be considered as a “smart contract”. State created by a chaincode is scoped exclusively to that chaincode and can’t be accessed directly by another chaincode. However, within the same network, given the appropriate permission a chaincode may invoke another chaincode to access its state.
下面fabcar这个chaincode里car有四属性
- Make string
json:"make" - Model string
json:"model" - Colour string
json:"colour" - Owner string
json:"owner"
以及各类交易方法:
- createCar 创建车
- queryAllCars 查询所有车
- changeCarOwner 改变车主
chaincode具体代码如下：
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* 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.
*/
/*
* The sample smart contract for documentation topic:
* Writing Your First Blockchain Application
*/
package main
/* Imports
* 4 utility libraries for formatting, handling bytes, reading and writing JSON, and string manipulation
* 2 specific Hyperledger Fabric specific libraries for Smart Contracts
*/
import (
"bytes"
"encoding/json"
"fmt"
"strconv"
"github.com/hyperledger/fabric/core/chaincode/shim"
sc "github.com/hyperledger/fabric/protos/peer"
)
// Define the Smart Contract structure
type SmartContract struct {
}
// Define the car structure, with 4 properties. Structure tags are used by encoding/json library 建立数据结构
type Car struct {
Make string `json:"make"`
Model string `json:"model"`
Colour string `json:"colour"`
Owner string `json:"owner"`
}
/*
* The Init method is called when the Smart Contract "fabcar" is instantiated by the blockchain network
* Best practice is to have any Ledger initialization in separate function -- see initLedger()
*/
func (s *SmartContract) Init(APIstub shim.ChaincodeStubInterface) sc.Response {
return shim.Success(nil)
}
/*
* The Invoke method is called as a result of an application request to run the Smart Contract "fabcar"
* The calling application program has also specified the particular smart contract function to be called, with arguments
*/
func (s *SmartContract) Invoke(APIstub shim.ChaincodeStubInterface) sc.Response {
// Retrieve the requested Smart Contract function and arguments
function, args := APIstub.GetFunctionAndParameters()
// Route to the appropriate handler function to interact with the ledger appropriately
if function == "queryCar" {
return s.queryCar(APIstub, args)
} else if function == "initLedger" {
return s.initLedger(APIstub)
} else if function == "createCar" {
return s.createCar(APIstub, args)
} else if function == "queryAllCars" {
return s.queryAllCars(APIstub)
} else if function == "changeCarOwner" {
return s.changeCarOwner(APIstub, args)
}
return shim.Error("Invalid Smart Contract function name.")
}
func (s *SmartContract) queryCar(APIstub shim.ChaincodeStubInterface, args []string) sc.Response {
if len(args) != 1 {
return shim.Error("Incorrect number of arguments. Expecting 1")
}
carAsBytes, _ := APIstub.GetState(args[0])
return shim.Success(carAsBytes)
}
// 初始化账簿10辆车
func (s *SmartContract) initLedger(APIstub shim.ChaincodeStubInterface) sc.Response {
cars := []Car{
Car{Make: "Toyota", Model: "Prius", Colour: "blue", Owner: "Tomoko"},
Car{Make: "Ford", Model: "Mustang", Colour: "red", Owner: "Brad"},
Car{Make: "Hyundai", Model: "Tucson", Colour: "green", Owner: "Jin Soo"},
Car{Make: "Volkswagen", Model: "Passat", Colour: "yellow", Owner: "Max"},
Car{Make: "Tesla", Model: "S", Colour: "black", Owner: "Adriana"},
Car{Make: "Peugeot", Model: "205", Colour: "purple", Owner: "Michel"},
Car{Make: "Chery", Model: "S22L", Colour: "white", Owner: "Aarav"},
Car{Make: "Fiat", Model: "Punto", Colour: "violet", Owner: "Pari"},
Car{Make: "Tata", Model: "Nano", Colour: "indigo", Owner: "Valeria"},
Car{Make: "Holden", Model: "Barina", Colour: "brown", Owner: "Shotaro"},
}
i := 0
for i < len(cars) {
fmt.Println("i is ", i)
carAsBytes, _ := json.Marshal(cars[i])
APIstub.PutState("CAR"+strconv.Itoa(i), carAsBytes)
fmt.Println("Added", cars[i])
i = i + 1
}
return shim.Success(nil)
}
func (s *SmartContract) createCar(APIstub shim.ChaincodeStubInterface, args []string) sc.Response {
if len(args) != 5 {
return shim.Error("Incorrect number of arguments. Expecting 5")
}
var car = Car{Make: args[1], Model: args[2], Colour: args[3], Owner: args[4]}
carAsBytes, _ := json.Marshal(car)
APIstub.PutState(args[0], carAsBytes)
return shim.Success(nil)
}
func (s *SmartContract) queryAllCars(APIstub shim.ChaincodeStubInterface) sc.Response {
startKey := "CAR0"
endKey := "CAR999"
resultsIterator, err := APIstub.GetStateByRange(startKey, endKey)
if err != nil {
return shim.Error(err.Error())
}
defer resultsIterator.Close()
// buffer is a JSON array containing QueryResults
var buffer bytes.Buffer
buffer.WriteString("[")
bArrayMemberAlreadyWritten := false
for resultsIterator.HasNext() {
queryResponse, err := resultsIterator.Next()
if err != nil {
return shim.Error(err.Error())
}
// Add a comma before array members, suppress it for the first array member
if bArrayMemberAlreadyWritten == true {
buffer.WriteString(",")
}
buffer.WriteString("{\"Key\":")
buffer.WriteString("\"")
buffer.WriteString(queryResponse.Key)
buffer.WriteString("\"")
buffer.WriteString(", \"Record\":")
// Record is a JSON object, so we write as-is
buffer.WriteString(string(queryResponse.Value))
buffer.WriteString("}")
bArrayMemberAlreadyWritten = true
}
buffer.WriteString("]")
fmt.Printf("- queryAllCars:\n%s\n", buffer.String())
return shim.Success(buffer.Bytes())
}
func (s *SmartContract) changeCarOwner(APIstub shim.ChaincodeStubInterface, args []string) sc.Response {
if len(args) != 2 {
return shim.Error("Incorrect number of arguments. Expecting 2")
}
carAsBytes, _ := APIstub.GetState(args[0])
car := Car{}
json.Unmarshal(carAsBytes, &car)
car.Owner = args[1]
carAsBytes, _ = json.Marshal(car)
APIstub.PutState(args[0], carAsBytes)
return shim.Success(nil)
}
// The main function is only relevant in unit test mode. Only included here for completeness.
func main() {
// Create a new Smart Contract
err := shim.Start(new(SmartContract))
if err != nil {
fmt.Printf("Error creating new Smart Contract: %s", err)
}
}构建区块链网络
启动脚本：startFabric.sh
#!/bin/bash
# Exit on first error
set -e
starttime=$(date +%s)
if [ ! -d ~/.hfc-key-store/ ]; then
mkdir ~/.hfc-key-store/
fi
cp $PWD/creds/* ~/.hfc-key-store/
# launch network; create channel and join peer to channel
# 启动区域连网络，并把各peer 加入Chanel
cd ../basic-network
./start.sh
# Now launch the CLI container in order to install, instantiate chaincode
# 启动Cli容器并安装，初始化链码
# and prime the ledger with our 10 cars
# 然后初始化10辆车
docker-compose -f ./docker-compose.yml up -d cli
docker exec -e "CORE_PEER_LOCALMSPID=Org1MSP" -e "CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/[email protected]/msp" cli peer chaincode install -n fabcar -v 1.0 -p github.com/fabcar
docker exec -e "CORE_PEER_LOCALMSPID=Org1MSP" -e "CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/[email protected]/msp" cli peer chaincode instantiate -o orderer.example.com:7050 -C mychannel -n fabcar -v 1.0 -c '{"Args":[""]}' -P "OR ('Org1MSP.member','Org2MSP.member')"
sleep 10
docker exec -e "CORE_PEER_LOCALMSPID=Org1MSP" -e "CORE_PEER_MSPCONFIGPATH=/opt/gopath/src/github.com/hyperledger/fabric/peer/crypto/peerOrganizations/org1.example.com/users/[email protected]/msp" cli peer chaincode invoke -o orderer.example.com:7050 -C mychannel -n fabcar -c '{"function":"initLedger","Args":[""]}'
printf "\nTotal execution time : $(($(date +%s) - starttime)) secs ...\n\n"执行脚本
root@ubuntu:~/fabcar# . ./startFabric.sh
docker-compose -f docker-compose.yml down
Removing network net_basic
docker-compose -f docker-compose.yml up -d ca.example.com orderer.example.com peer0.org1.example.com couchdb
Creating network "net_basic" with the default driver
Creating couchdb ...
Creating ca.example.com ...
Creating orderer.example.com ...
Creating ca.example.com
Creating couchdb
Creating orderer.example.com ... done
Creating peer0.org1.example.com ...
Creating peer0.org1.example.com ... done
# wait for Hyperledger Fabric to start
# incase of errors when running later commands, issue export FABRIC_START_TIMEOUT=<larger number>
export FABRIC_START_TIMEOUT=10
#echo ${FABRIC_START_TIMEOUT}
sleep ${FABRIC_START_TIMEOUT}
# Create the channel
docker exec -e "CORE_PEER_LOCALMSPID=Org1MSP" -e "CORE_PEER_MSPCONFIGPATH=/etc/hyperledger/msp/users/[email protected]/msp" peer0.org1.example.com peer channel create -o orderer.example.com:7050 -c mychannel -f /etc/hyperledger/configtx/channel.tx
2017-08-29 19:12:19.929 UTC [msp] GetLocalMSP -> DEBU 001 Returning existing local MSP
2017-08-29 19:12:19.929 UTC [msp] GetDefaultSigningIdentity -> DEBU 002 Obtaining default signing identity
2017-08-29 19:12:19.933 UTC [channelCmd] InitCmdFactory -> INFO 003 Endorser and orderer connections initialized
2017-08-29 19:12:19.933 UTC [msp] GetLocalMSP -> DEBU 004 Returning existing local MSP
2017-08-29 19:12:19.933 UTC [msp] GetDefaultSigningIdentity -> DEBU 005 Obtaining default signing identity
2017-08-29 19:12:19.935 UTC [msp] GetLocalMSP -> DEBU 006 Returning existing local MSP
2017-08-29 19:12:19.935 UTC [msp] GetDefaultSigningIdentity -> DEBU 007 Obtaining default signing identity
2017-08-29 19:12:19.935 UTC [msp/identity] Sign -> DEBU 008 Sign: plaintext: 0A8C060A074F7267314D53501280062D...53616D706C65436F6E736F727469756D
2017-08-29 19:12:19.935 UTC [msp/identity] Sign -> DEBU 009 Sign: digest: AB4CF53AE7F25F55FC853E7AA8FA847F9ADB7F5669C251C029313639CBE3EB0C
2017-08-29 19:12:19.935 UTC [msp] GetLocalMSP -> DEBU 00a Returning existing local MSP
2017-08-29 19:12:19.935 UTC [msp] GetDefaultSigningIdentity -> DEBU 00b Obtaining default signing identity
2017-08-29 19:12:19.936 UTC [msp] GetLocalMSP -> DEBU 00c Returning existing local MSP
2017-08-29 19:12:19.936 UTC [msp] GetDefaultSigningIdentity -> DEBU 00d Obtaining default signing identity
2017-08-29 19:12:19.936 UTC [msp/identity] Sign -> DEBU 00e Sign: plaintext: 0AC3060A1508021A060893F996CD0522...04CD8921E4BA83A1D6A2088DF251B740
2017-08-29 19:12:19.936 UTC [msp/identity] Sign -> DEBU 00f Sign: digest: BF6CC7A8635CE11B92CE895142A4377D9A70CB14EA9ACBF53CD39E5E1E010F06
2017-08-29 19:12:20.084 UTC [msp] GetLocalMSP -> DEBU 010 Returning existing local MSP
2017-08-29 19:12:20.084 UTC [msp] GetDefaultSigningIdentity -> DEBU 011 Obtaining default signing identity
2017-08-29 19:12:20.084 UTC [msp] GetLocalMSP -> DEBU 012 Returning existing local MSP
2017-08-29 19:12:20.084 UTC [msp] GetDefaultSigningIdentity -> DEBU 013 Obtaining default signing identity
2017-08-29 19:12:20.084 UTC [msp/identity] Sign -> DEBU 014 Sign: plaintext: 0AC3060A1508021A060894F996CD0522...9BCAC7F7286212080A021A0012021A00
2017-08-29 19:12:20.084 UTC [msp/identity] Sign -> DEBU 015 Sign: digest: 3FD3A5C2FA53214CEFC3B47DFC4DEE78DF2BBC1646C77C2CA3039A7E83378931
2017-08-29 19:12:20.086 UTC [channelCmd] readBlock -> DEBU 016 Got status:*orderer.DeliverResponse_Status
2017-08-29 19:12:20.086 UTC [msp] GetLocalMSP -> DEBU 017 Returning existing local MSP
2017-08-29 19:12:20.086 UTC [msp] GetDefaultSigningIdentity -> DEBU 018 Obtaining default signing identity
2017-08-29 19:12:20.090 UTC [channelCmd] InitCmdFactory -> INFO 019 Endorser and orderer connections initialized
2017-08-29 19:12:20.290 UTC [msp] GetLocalMSP -> DEBU 01a Returning existing local MSP
2017-08-29 19:12:20.290 UTC [msp] GetDefaultSigningIdentity -> DEBU 01b Obtaining default signing identity
2017-08-29 19:12:20.290 UTC [msp] GetLocalMSP -> DEBU 01c Returning existing local MSP
2017-08-29 19:12:20.290 UTC [msp] GetDefaultSigningIdentity -> DEBU 01d Obtaining default signing identity
2017-08-29 19:12:20.290 UTC [msp/identity] Sign -> DEBU 01e Sign: plaintext: 0AC3060A1508021A060894F996CD0522...AA1D768A0B9D12080A021A0012021A00
2017-08-29 19:12:20.290 UTC [msp/identity] Sign -> DEBU 01f Sign: digest: 560CFC8CB4E9D591BE81CBD50A50107BE8B074021595CBB1F9DFD8EC5A78C857
2017-08-29 19:12:20.297 UTC [channelCmd] readBlock -> DEBU 020 Received block:0
2017-08-29 19:12:20.299 UTC [main] main -> INFO 021 Exiting.....
# Join peer0.org1.example.com to the channel.
docker exec -e "CORE_PEER_LOCALMSPID=Org1MSP" -e "CORE_PEER_MSPCONFIGPATH=/etc/hyperledger/msp/users/[email protected]/msp" peer0.org1.example.com peer channel join -b mychannel.block
2017-08-29 19:12:20.602 UTC [msp] GetLocalMSP -> DEBU 001 Returning existing local MSP
2017-08-29 19:12:20.602 UTC [msp] GetDefaultSigningIdentity -> DEBU 002 Obtaining default signing identity
2017-08-29 19:12:20.607 UTC [channelCmd] InitCmdFactory -> INFO 003 Endorser and orderer connections initialized
2017-08-29 19:12:20.610 UTC [msp/identity] Sign -> DEBU 004 Sign: plaintext: 0A8A070A5C08011A0C0894F996CD0510...9BD6C0AB03541A080A000A000A000A00
2017-08-29 19:12:20.610 UTC [msp/identity] Sign -> DEBU 005 Sign: digest: F428B9E87CAC4F0EC5EB57736BDCCBAE1E1972C69B77467D2EE41B783867FCA3
2017-08-29 19:12:20.813 UTC [channelCmd] executeJoin -> INFO 006 Peer joined the channel!
2017-08-29 19:12:20.813 UTC [main] main -> INFO 007 Exiting.....
Pulling cli (hyperledger/fabric-tools:x86_64-1.0.0)...
x86_64-1.0.0: Pulling from hyperledger/fabric-tools
aafe6b5e13de: Already exists
0a2b43a72660: Already exists
18bdd1e546d2: Already exists
8198342c3e05: Already exists
f56970a44fd4: Already exists
e32b597e7839: Already exists
a6e362fc71c4: Already exists
e21570e54f61: Already exists
66620db3cda6: Already exists
0548c619fbb7: Already exists
e084aff94b0b: Already exists
fac34f94b9b9: Pull complete
d4ca6b61a36e: Pull complete
6378740a852a: Pull complete
75a35cd33119: Pull complete
Digest: sha256:c107430c14344f4f37f0882f3eb8591520abd699a0b9da2b507f7527505612a7
Status: Downloaded newer image for hyperledger/fabric-tools:x86_64-1.0.0
Creating cli ...
Creating cli ... done
2017-08-29 19:12:38.644 UTC [msp] GetLocalMSP -> DEBU 001 Returning existing local MSP
2017-08-29 19:12:38.645 UTC [msp] GetDefaultSigningIdentity -> DEBU 002 Obtaining default signing identity
2017-08-29 19:12:38.645 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 003 Using default escc
2017-08-29 19:12:38.645 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 004 Using default vscc
2017-08-29 19:12:39.397 UTC [golang-platform] getCodeFromFS -> DEBU 005 getCodeFromFS github.com/fabcar
2017-08-29 19:12:40.404 UTC [golang-platform] func1 -> DEBU 006 Discarding GOROOT package bytes
2017-08-29 19:12:40.404 UTC [golang-platform] func1 -> DEBU 007 Discarding GOROOT package encoding/json
2017-08-29 19:12:40.404 UTC [golang-platform] func1 -> DEBU 008 Discarding GOROOT package fmt
2017-08-29 19:12:40.404 UTC [golang-platform] func1 -> DEBU 009 Discarding provided package github.com/hyperledger/fabric/core/chaincode/shim
2017-08-29 19:12:40.404 UTC [golang-platform] func1 -> DEBU 00a Discarding provided package github.com/hyperledger/fabric/protos/peer
2017-08-29 19:12:40.404 UTC [golang-platform] func1 -> DEBU 00b Discarding GOROOT package strconv
2017-08-29 19:12:40.405 UTC [golang-platform] GetDeploymentPayload -> DEBU 00c done
2017-08-29 19:12:40.412 UTC [msp/identity] Sign -> DEBU 00d Sign: plaintext: 0A8A070A5C08031A0C08A8F996CD0510...939FFF060000FFFF9C08DC0700200000
2017-08-29 19:12:40.412 UTC [msp/identity] Sign -> DEBU 00e Sign: digest: 46FFD3912E51469B57E87B5832DF2FC27CCABA13316494E0418B2B600C2233DA
2017-08-29 19:12:40.419 UTC [chaincodeCmd] install -> DEBU 00f Installed remotely response:<status:200 payload:"OK" >
2017-08-29 19:12:40.419 UTC [main] main -> INFO 010 Exiting.....
2017-08-29 19:12:40.631 UTC [msp] GetLocalMSP -> DEBU 001 Returning existing local MSP
2017-08-29 19:12:40.631 UTC [msp] GetDefaultSigningIdentity -> DEBU 002 Obtaining default signing identity
2017-08-29 19:12:40.632 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 003 Using default escc
2017-08-29 19:12:40.632 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 004 Using default vscc
2017-08-29 19:12:40.634 UTC [msp/identity] Sign -> DEBU 005 Sign: plaintext: 0A95070A6708031A0C08A8F996CD0510...324D53500A04657363630A0476736363
2017-08-29 19:12:40.634 UTC [msp/identity] Sign -> DEBU 006 Sign: digest: 85C3D93AD44FDAAF2A1A92BC1FC4DAEFD2E1F796880B36A86673E4E3CE266EBD
2017-08-29 19:13:53.027 UTC [msp/identity] Sign -> DEBU 007 Sign: plaintext: 0A95070A6708031A0C08A8F996CD0510...57E2BBF703C567C9EC8E912FECD8AE3D
2017-08-29 19:13:53.027 UTC [msp/identity] Sign -> DEBU 008 Sign: digest: 7132F6CEBF94F7C478AC63DFE841FDBEE31EC4C78B67283AB373A2D811A5BEE1
2017-08-29 19:13:53.032 UTC [main] main -> INFO 009 Exiting.....
2017-08-29 19:14:03.355 UTC [msp] GetLocalMSP -> DEBU 001 Returning existing local MSP
2017-08-29 19:14:03.355 UTC [msp] GetDefaultSigningIdentity -> DEBU 002 Obtaining default signing identity
2017-08-29 19:14:03.358 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 003 Using default escc
2017-08-29 19:14:03.358 UTC [chaincodeCmd] checkChaincodeCmdParams -> INFO 004 Using default vscc
2017-08-29 19:14:03.360 UTC [msp/identity] Sign -> DEBU 005 Sign: plaintext: 0A97070A6908031A0C08FBF996CD0510...1A0E0A0A696E69744C65646765720A00
2017-08-29 19:14:03.360 UTC [msp/identity] Sign -> DEBU 006 Sign: digest: EBA72A2A263CFB4245DB7C51BCD134E981CB0229F5022E8C485FBDAF7B3B703B
2017-08-29 19:14:03.412 UTC [msp/identity] Sign -> DEBU 007 Sign: plaintext: 0A97070A6908031A0C08FBF996CD0510...D9166A19C3A967F8BEE99CABD206C9D6
2017-08-29 19:14:03.412 UTC [msp/identity] Sign -> DEBU 008 Sign: digest: D5386F73796B0FCE332877D1ACF454DDE073899A609867B68B35F459382A2F66
2017-08-29 19:14:03.418 UTC [chaincodeCmd] chaincodeInvokeOrQuery -> DEBU 009 ESCC invoke result: version:1 response:<status:200 message:"OK" > payload:"\n \301G\277h\207t\276[\r\314\30631um\345J[#\356%0\010\320\317\n\016y\255\356\322\322\022\267\006\n\240\006\022\205\006\n\006fabcar\022\372\005\032J\n\004CAR0\032B{\"make\":\"Toyota\",\"model\":\"Prius\",\"colour\":\"blue\",\"owner\":\"Tomoko\"}\032G\n\004CAR1\032?{\"make\":\"Ford\",\"model\":\"Mustang\",\"colour\":\"red\",\"owner\":\"Brad\"}\032N\n\004CAR2\032F{\"make\":\"Hyundai\",\"model\":\"Tucson\",\"colour\":\"green\",\"owner\":\"Jin Soo\"}\032N\n\004CAR3\032F{\"make\":\"Volkswagen\",\"model\":\"Passat\",\"colour\":\"yellow\",\"owner\":\"Max\"}\032G\n\004CAR4\032?{\"make\":\"Tesla\",\"model\":\"S\",\"colour\":\"black\",\"owner\":\"Adriana\"}\032K\n\004CAR5\032C{\"make\":\"Peugeot\",\"model\":\"205\",\"colour\":\"purple\",\"owner\":\"Michel\"}\032H\n\004CAR6\032@{\"make\":\"Chery\",\"model\":\"S22L\",\"colour\":\"white\",\"owner\":\"Aarav\"}\032H\n\004CAR7\032@{\"make\":\"Fiat\",\"model\":\"Punto\",\"colour\":\"violet\",\"owner\":\"Pari\"}\032J\n\004CAR8\032B{\"make\":\"Tata\",\"model\":\"Nano\",\"colour\":\"indigo\",\"owner\":\"Valeria\"}\032M\n\004CAR9\032E{\"make\":\"Holden\",\"model\":\"Barina\",\"colour\":\"brown\",\"owner\":\"Shotaro\"}\022\026\n\004lscc\022\016\n\014\n\006fabcar\022\002\010\001\032\003\010\310\001\"\r\022\006fabcar\032\0031.0" endorsement:<endorser:"\n\007Org1MSP\022\374\005-----BEGIN -----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\nHE6DFYvvBCUnicUh\n-----END -----\n" signature:"0E\002!\000\234s\024\311\257\272\315\375:\355z\260}\336X\214\034\372MP\374L`\251\0034\217\327g\274\300\263\002 \rD]\340\332\343\032+\312\364vox\277JV\331\026j\031\303\251g\370\276\351\234\253\322\006\311\326" >
2017-08-29 19:14:03.419 UTC [chaincodeCmd] chaincodeInvokeOrQuery -> INFO 00a Chaincode invoke successful. result: status:200
2017-08-29 19:14:03.419 UTC [main] main -> INFO 00b Exiting.....
Total execution time : 122 secs ...
root@ubuntu:~/basic-network#CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
3b2978bd8bb9 dev-peer0.org1.example.com-fabcar-1.0 "chaincode -peer.a..." 15 hours ago Up 15 hours dev-peer0.org1.example.com-fabcar-1.0
e58f60336983 hyperledger/fabric-tools:x86_64-1.0.0 "/bin/bash" 15 hours ago Up 15 hours cli
efecad2b6d36 hyperledger/fabric-peer:x86_64-1.0.0 "peer node start" 15 hours ago Up 15 hours 0.0.0.0:7051->7051/tcp, 0.0.0.0:7053->7053/tcp peer0.org1.example.com
8bf3d70e5f42 hyperledger/fabric-ca:x86_64-1.0.0 "sh -c 'fabric-ca-..." 15 hours ago Up 15 hours 0.0.0.0:7054->7054/tcp ca.example.com
dd58d8c032e3 hyperledger/fabric-orderer:x86_64-1.0.0 "orderer" 15 hours ago Up 15 hours 0.0.0.0:7050->7050/tcp orderer.example.com
8077c0b69096 hyperledger/fabric-couchdb:x86_64-1.0.0 "tini -- /docker-e..." 15 hours ago Up 15 hours 4369/tcp, 9100/tcp, 0.0.0.0:5984->5984/tcp couchdb执行区块链交易
通过以上过程完成构建一个Blockchain Network，接下来我们将通过Node.Js编写的程序Application执行交易。
安装Fabric Node SDK
root@ubuntu:~/fabcar# npm install编写查询程序query.js
'use strict';
/*
*
* SPDX-License-Identifier: Apache-2.0
*/
/*
* Hyperledger Fabric Sample Query Program
*/
var hfc = require('fabric-client');
var path = require('path');
var options = {
wallet_path: path.join(__dirname, './creds'),
user_id: 'PeerAdmin',
channel_id: 'mychannel',
chaincode_id: 'fabcar',
network_url: 'grpc://localhost:7051',
};
var channel = {};
var client = null;
Promise.resolve().then(() => {
console.log("Create a client and set the wallet location");
client = new hfc();
return hfc.newDefaultKeyValueStore({ path: options.wallet_path });
}).then((wallet) => {
console.log("Set wallet path, and associate user ", options.user_id, " with application");
client.setStateStore(wallet);
return client.getUserContext(options.user_id, true);
}).then((user) => {
console.log("Check user is enrolled, and set a query URL in the network");
if (user === undefined || user.isEnrolled() === false) {
console.error("User not defined, or not enrolled - error");
}
channel = client.newChannel(options.channel_id);
channel.addPeer(client.newPeer(options.network_url));
return;
}).then(() => {
console.log("Make query");
var transaction_id = client.newTransactionID();
console.log("Assigning transaction_id: ", transaction_id._transaction_id);
// queryCar - requires 1 argument, ex: args: ['CAR4'],
// queryAllCars - requires no arguments , ex: args: [''],
const request = {
chaincodeId: options.chaincode_id,
txId: transaction_id,
fcn: 'queryAllCars',
args: ['']
};
return channel.queryByChaincode(request);
}).then((query_responses) => {
console.log("returned from query");
if (!query_responses.length) {
console.log("No payloads were returned from query");
} else {
console.log("Query result count = ", query_responses.length)
}
if (query_responses[0] instanceof Error) {
console.error("error from query = ", query_responses[0]);
}
console.log("Response is ", query_responses[0].toString());
}).catch((err) => {
console.error("Caught Error", err);
});执行query.js
root@ubuntu:~/fabcar# node query.js
Create a client and set the wallet location
Set wallet path, and associate user PeerAdmin with application
Check user is enrolled, and set a query URL in the network
Make query
Assigning transaction_id: aa4384c6e00c25965bfd7690468003ae5c602e3d70df5eccca6dbf9657cce077
returned from query
Query result count = 1
Response is [{"Key":"CAR0", "Record":{"colour":"blue","make":"Toyota","model":"Prius","owner":"Tomoko"}},{"Key":"CAR1", "Record":{"colour":"red","make":"Ford","model":"Mustang","owner":"Brad"}},{"Key":"CAR2", "Record":{"colour":"green","make":"Hyundai","model":"Tucson","owner":"Jin Soo"}},{"Key":"CAR3", "Record":{"colour":"yellow","make":"Volkswagen","model":"Passat","owner":"Max"}},{"Key":"CAR4", "Record":{"colour":"black","make":"Tesla","model":"S","owner":"Adriana"}},{"Key":"CAR5", "Record":{"colour":"purple","make":"Peugeot","model":"205","owner":"Michel"}},{"Key":"CAR6", "Record":{"colour":"white","make":"Chery","model":"S22L","owner":"Aarav"}},{"Key":"CAR7", "Record":{"colour":"violet","make":"Fiat","model":"Punto","owner":"Pari"}},{"Key":"CAR8", "Record":{"colour":"indigo","make":"Tata","model":"Nano","owner":"Valeria"}},{"Key":"CAR9", "Record":{"colour":"brown","make":"Holden","model":"Barina","owner":"Shotaro"}}]
root@ubuntu:~/fabcar#
改变车主， 把”Adriana”的”CAR4”, “Tesla”,”model”:”S” 的owner改为”Zheng rui”
changeowner.js
'use strict';
/*
* Copyright IBM Corp All Rights Reserved
*
* SPDX-License-Identifier: Apache-2.0
*/
/*
* Chaincode Invoke
*/
var hfc = require('fabric-client');
var path = require('path');
var util = require('util');
var options = {
wallet_path: path.join(__dirname, './creds'),
user_id: 'PeerAdmin',
channel_id: 'mychannel',
chaincode_id: 'fabcar',
peer_url: 'grpc://localhost:7051',
event_url: 'grpc://localhost:7053',
orderer_url: 'grpc://localhost:7050'
};
var channel = {};
var client = null;
var targets = [];
var tx_id = null;
Promise.resolve().then(() => {
console.log("Create a client and set the wallet location");
client = new hfc();
return hfc.newDefaultKeyValueStore({ path: options.wallet_path });
}).then((wallet) => {
console.log("Set wallet path, and associate user ", options.user_id, " with application");
client.setStateStore(wallet);
return client.getUserContext(options.user_id, true);
}).then((user) => {
console.log("Check user is enrolled, and set a query URL in the network");
if (user === undefined || user.isEnrolled() === false) {
console.error("User not defined, or not enrolled - error");
}
channel = client.newChannel(options.channel_id);
var peerObj = client.newPeer(options.peer_url);
channel.addPeer(peerObj);
channel.addOrderer(client.newOrderer(options.orderer_url));
targets.push(peerObj);
return;
}).then(() => {
tx_id = client.newTransactionID();
console.log("Assigning transaction_id: ", tx_id._transaction_id);
// createCar - requires 5 args, ex: args: ['CAR11', 'Honda', 'Accord', 'Black', 'Tom'],
// changeCarOwner - requires 2 args , ex: args: ['CAR10', 'Barry'],
// send proposal to endorser
var request = {
targets: targets,
chaincodeId: options.chaincode_id,
fcn: 'changeCarOwner',
args: ['CAR4', 'Zheng rui'],
chainId: options.channel_id,
txId: tx_id
};
return channel.sendTransactionProposal(request);
}).then((results) => {
var proposalResponses = results[0];
var proposal = results[1];
var header = results[2];
let isProposalGood = false;
if (proposalResponses && proposalResponses[0].response &&
proposalResponses[0].response.status === 200) {
isProposalGood = true;
console.log('transaction proposal was good');
} else {
console.error('transaction proposal was bad');
}
if (isProposalGood) {
console.log(util.format(
'Successfully sent Proposal and received ProposalResponse: Status - %s, message - "%s", metadata - "%s", endorsement signature: %s',
proposalResponses[0].response.status, proposalResponses[0].response.message,
proposalResponses[0].response.payload, proposalResponses[0].endorsement.signature));
var request = {
proposalResponses: proposalResponses,
proposal: proposal,
header: header
};
// set the transaction listener and set a timeout of 30sec
// if the transaction did not get committed within the timeout period,
// fail the test
var transactionID = tx_id.getTransactionID();
var eventPromises = [];
let eh = client.newEventHub();
eh.setPeerAddr(options.event_url);
eh.connect();
let txPromise = new Promise((resolve, reject) => {
let handle = setTimeout(() => {
eh.disconnect();
reject();
}, 30000);
eh.registerTxEvent(transactionID, (tx, code) => {
clearTimeout(handle);
eh.unregisterTxEvent(transactionID);
eh.disconnect();
if (code !== 'VALID') {
console.error(
'The transaction was invalid, code = ' + code);
reject();
} else {
console.log(
'The transaction has been committed on peer ' +
eh._ep._endpoint.addr);
resolve();
}
});
});
eventPromises.push(txPromise);
var sendPromise = channel.sendTransaction(request);
return Promise.all([sendPromise].concat(eventPromises)).then((results) => {
console.log(' event promise all complete and testing complete');
return results[0]; // the first returned value is from the 'sendPromise' which is from the 'sendTransaction()' call
}).catch((err) => {
console.error(
'Failed to send transaction and get notifications within the timeout period.'
);
return 'Failed to send transaction and get notifications within the timeout period.';
});
} else {
console.error(
'Failed to send Proposal or receive valid response. Response null or status is not 200. exiting...'
);
return 'Failed to send Proposal or receive valid response. Response null or status is not 200. exiting...';
}
}, (err) => {
console.error('Failed to send proposal due to error: ' + err.stack ? err.stack :
err);
return 'Failed to send proposal due to error: ' + err.stack ? err.stack :
err;
}).then((response) => {
if (response.status === 'SUCCESS') {
console.log('Successfully sent transaction to the orderer.');
return tx_id.getTransactionID();
} else {
console.error('Failed to order the transaction. Error code: ' + response.status);
return 'Failed to order the transaction. Error code: ' + response.status;
}
}, (err) => {
console.error('Failed to send transaction due to error: ' + err.stack ? err
.stack : err);
return 'Failed to send transaction due to error: ' + err.stack ? err.stack :
err;
});
执行改车主程序
root@ubuntu:~/fabcar# node changeowner.js
Create a client and set the wallet location
Set wallet path, and associate user PeerAdmin with application
Check user is enrolled, and set a query URL in the network
Assigning transaction_id: c5263d9f94a0876ea80fcf4d3eb5ff914525afdcf521e7a21a64526b88bb023e
transaction proposal was good
Successfully sent Proposal and received ProposalResponse: Status - 200, message - "OK", metadata - "", endorsement signature: 0D 5�"���b�Dc��Hb7��-n�Hx[�� 5�{h6���g���v�� 7���DZ�6LA��
info: [EventHub.js]: _connect - options {}
The transaction has been committed on peer localhost:7053
event promise all complete and testing complete
Successfully sent transaction to the orderer.
root@ubuntu:~/fabcar# 再查询一下
root@ubuntu:~/fabcar# node query.js
Create a client and set the wallet location
Set wallet path, and associate user PeerAdmin with application
Check user is enrolled, and set a query URL in the network
Make query
Assigning transaction_id: 757d64fa926de8ed57c944e3e92b470d76cc37a21b9cea1cf299e7177daf7f77
returned from query
Query result count = 1
Response is [{"Key":"CAR0", "Record":{"colour":"blue","make":"Toyota","model":"Prius","owner":"Tomoko"}},{"Key":"CAR1", "Record":{"colour":"red","make":"Ford","model":"Mustang","owner":"Brad"}},{"Key":"CAR2", "Record":{"colour":"green","make":"Hyundai","model":"Tucson","owner":"Jin Soo"}},{"Key":"CAR3", "Record":{"colour":"yellow","make":"Volkswagen","model":"Passat","owner":"Max"}},{"Key":"CAR4", "Record":{"colour":"black","make":"Tesla","model":"S","owner":"Zheng rui"}},{"Key":"CAR5", "Record":{"colour":"purple","make":"Peugeot","model":"205","owner":"Michel"}},{"Key":"CAR6", "Record":{"colour":"white","make":"Chery","model":"S22L","owner":"Aarav"}},{"Key":"CAR7", "Record":{"colour":"violet","make":"Fiat","model":"Punto","owner":"Pari"}},{"Key":"CAR8", "Record":{"colour":"indigo","make":"Tata","model":"Nano","owner":"Valeria"}},{"Key":"CAR9", "Record":{"colour":"brown","make":"Holden","model":"Barina","owner":"Shotaro"}}]
{“Key”:”CAR4”, “Record”:{“colour”:”black”,”make”:”Tesla”,”model”:”S”,”owner”:”Zheng rui”}}
车主变为“Zheng rui”， 是不是很简单。
为什么要用区块链？
引一下Hyperledger的官方说法: 区块链技术将带来的广泛、根本的革命，自互联网以来，没有一个技术能与其潜力相比。区块链是一个端对端的分布式账薄，叠加了共识机制，加上“智能合约”系统和其他辅助技术。所有这些共同作用，可以用来构建新一代的交易应用，在核心上建立信任、责任和透明度，同时精简业务流程和法律约束。
我们可以把它想象为一个交易市场的操作系统、数据共享网络、微货币、以及一个去中心化的数字社区。它有极大降低现实世界中完成交易的成本和复杂性的潜能。
只有一个开源、协作的软件开发方法才能够确保所需要的透明度、长期性、互操作性和支持，将区块链技术带进主流商业应用。超级账本的宗旨是——创建从事区块链框架和平台搭建的软件开发人员社区。