概述
在上一篇博客中我们已经简单分析了Fabric启动时日志，接下来我们分析一下script.sh脚本和chaincode的源代码。
进入~/go/src/github.com/hyperledger/fabric-samples/first-network/scripts目录下，找出其中与链码有关的部分：
installChaincode () {
PEER=$1
setGlobals $PEER
peer chaincode install -n mycc -v 1.0 -p github.com/hyperledger/fabric/examples/chaincode/go/chaincode_example02 >&log.txt
res=$?
cat log.txt
verifyResult $res "Chaincode installation on remote peer PEER$PEER has Failed"
echo "===================== Chaincode is installed on remote peer PEER$PEER ===================== "
echo
}
instantiateChaincode () {
PEER=$1
setGlobals $PEER
# while 'peer chaincode' command can get the orderer endpoint from the peer (if join was successful),
# lets supply it directly as we know it using the "-o" option
if [ -z "$CORE_PEER_TLS_ENABLED" -o "$CORE_PEER_TLS_ENABLED" = "false" ]; then
peer chaincode instantiate -o orderer.example.com:7050 -C $CHANNEL_NAME -n mycc -v 1.0 -c '{"Args":["init","a","100","b","200"]}' -P "OR ('Org1MSP.member','Org2MSP.member')" >&log.txt
else
peer chaincode instantiate -o orderer.example.com:7050 --tls $CORE_PEER_TLS_ENABLED --cafile $ORDERER_CA -C $CHANNEL_NAME -n mycc -v 1.0 -c '{"Args":["init","a","100","b","200"]}' -P "OR ('Org1MSP.member','Org2MSP.member')" >&log.txt
fi
res=$?
cat log.txt
verifyResult $res "Chaincode instantiation on PEER$PEER on channel '$CHANNEL_NAME' failed"
echo "===================== Chaincode Instantiation on PEER$PEER on channel '$CHANNEL_NAME' is successful ===================== "
echo
}
chaincodeQuery () {
PEER=$1
echo "===================== Querying on PEER$PEER on channel '$CHANNEL_NAME'... ===================== "
setGlobals $PEER
local rc=1
local starttime=$(date +%s)
# continue to poll
# we either get a successful response, or reach TIMEOUT
while test "$(($(date +%s)-starttime))" -lt "$TIMEOUT" -a $rc -ne 0
do
sleep $DELAY
echo "Attempting to Query PEER$PEER ...$(($(date +%s)-starttime)) secs"
peer chaincode query -C $CHANNEL_NAME -n mycc -c '{"Args":["query","a"]}' >&log.txt
test $? -eq 0 && VALUE=$(cat log.txt | awk '/Query Result/ {print $NF}')
test "$VALUE" = "$2" && let rc=0
done
echo
cat log.txt
if test $rc -eq 0 ; then
echo "===================== Query on PEER$PEER on channel '$CHANNEL_NAME' is successful ===================== "
else
echo "!!!!!!!!!!!!!!! Query result on PEER$PEER is INVALID !!!!!!!!!!!!!!!!"
echo "================== ERROR !!! FAILED to execute End-2-End Scenario =================="
echo
exit 1
fi
}
chaincodeInvoke () {
PEER=$1
setGlobals $PEER
# while 'peer chaincode' command can get the orderer endpoint from the peer (if join was successful),
# lets supply it directly as we know it using the "-o" option
if [ -z "$CORE_PEER_TLS_ENABLED" -o "$CORE_PEER_TLS_ENABLED" = "false" ]; then
peer chaincode invoke -o orderer.example.com:7050 -C $CHANNEL_NAME -n mycc -c '{"Args":["invoke","a","b","10"]}' >&log.txt
else
peer chaincode invoke -o orderer.example.com:7050 --tls $CORE_PEER_TLS_ENABLED --cafile $ORDERER_CA -C $CHANNEL_NAME -n mycc -c '{"Args":["invoke","a","b","10"]}' >&log.txt
fi
res=$?
cat log.txt
verifyResult $res "Invoke execution on PEER$PEER failed "
echo "===================== Invoke transaction on PEER$PEER on channel '$CHANNEL_NAME' is successful ===================== "
echo
}
接下来我们分析一下各个函数方法：
1、installChaincode ()将区块链进行打包，然后上传到某一个节点上。
2、instantiateChaincode ()将链码初始化，其中
peer chaincode instantiate -o orderer.example.com:7050 -C $CHANNEL_NAME -n mycc -v 1.0 -c '{"Args":["init","a","100","b","200"]}' -P "OR 调用了我们上一篇博文中所看到的chaincode_example02.go中的init方法,其中init源代码部分如下：
func (t *SimpleChaincode) Init(stub shim.ChaincodeStubInterface) pb.Response {
fmt.Println("ex02 Init")
_, args := stub.GetFunctionAndParameters()
var A, B string // Entities
var Aval, Bval int // Asset holdings
var err error
//接受了四个参数
if len(args) != 4 {
return shim.Error("Incorrect number of arguments. Expecting 4")
}
// Initialize the chaincode
//A代表a
A = args[0]
//A的value是100
Aval, err = strconv.Atoi(args[1])
if err != nil {
return shim.Error("Expecting integer value for asset holding")
}
//B代表b
B = args[2]
//b的value是200
Bval, err = strconv.Atoi(args[3])
if err != nil {
return shim.Error("Expecting integer value for asset holding")
}
fmt.Printf("Aval = %d, Bval = %dn", Aval, Bval)
// Write the state to the ledger
err = stub.PutState(A, []byte(strconv.Itoa(Aval)))
if err != nil {
return shim.Error(err.Error())
}
err = stub.PutState(B, []byte(strconv.Itoa(Bval)))
if err != nil {
return shim.Error(err.Error())
}
return shim.Success(nil)
}
它创建了a,b两个账户，并分别初始化
3、chaincodeQuery ()代表调用查询方法，其中有这么一句：
peer chaincode query -C $CHANNEL_NAME -n mycc -c '{"Args":["query","a"]}' >&log.txt它调用了我们上一篇博文中所看到的chaincode_example02.go中的query方法,查询a账户的余额，其中query源代码部分如下：
// query callback representing the query of a chaincode
func (t *SimpleChaincode) query(stub shim.ChaincodeStubInterface, args []string) pb.Response {
var A string // Entities
var err error
if len(args) != 1 {
return shim.Error("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 shim.Error(jsonResp)
}
if Avalbytes == nil {
jsonResp := "{"Error":"Nil amount for " + A + ""}"
return shim.Error(jsonResp)
}
jsonResp := "{"Name":"" + A + "","Amount":"" + string(Avalbytes) + ""}"
fmt.Printf("Query Response:%sn", jsonResp)
return shim.Success(Avalbytes)
}
其实就是返回a账户的余额，在上一篇博文的日志输出中，我们也会看到相应的结果，
4、chaincodeInvoke ()方法中中有这样一句话：
peer chaincode invoke -o orderer.example.com:7050 -C $CHANNEL_NAME -n mycc -c '{"Args":["invoke","a","b","10"]}' >&log.txt它调用了我们上一篇博文中所看到的chaincode_example02.go中的invoke方法,查询a账户的余额，其中invoke源代码部分如下：
// Transaction makes payment of X units from A to B
func (t *SimpleChaincode) invoke(stub shim.ChaincodeStubInterface, args []string) pb.Response {
var A, B string // Entities
var Aval, Bval int // Asset holdings
var X int // Transaction value
var err error
//接收三个参数
if len(args) != 3 {
return shim.Error("Incorrect number of arguments. Expecting 3")
}
//两个账户的名称
A = args[0]
B = args[1]
//查询两个账户的值
Avalbytes, err := stub.GetState(A)
if err != nil {
return shim.Error("Failed to get state")
}
if Avalbytes == nil {
return shim.Error("Entity not found")
}
//数值转换，在fabric中存的值都是byte数组，我们需要的是整型
Aval, _ = strconv.Atoi(string(Avalbytes))
Bvalbytes, err := stub.GetState(B)
if err != nil {
return shim.Error("Failed to get state")
}
if Bvalbytes == nil {
return shim.Error("Entity not found")
}
Bval, _ = strconv.Atoi(string(Bvalbytes))
// 把第三个参数赋值给了x
X, err = strconv.Atoi(args[2])
if err != nil {
return shim.Error("Invalid transaction amount, expecting a integer value")
}
//转账操作
Aval = Aval - X
Bval = Bval + X
fmt.Printf("Aval = %d, Bval = %dn", Aval, Bval)
// Write the state back to the ledger
//更新账本
err = stub.PutState(A, []byte(strconv.Itoa(Aval)))
if err != nil {
return shim.Error(err.Error())
}
err = stub.PutState(B, []byte(strconv.Itoa(Bval)))
if err != nil {
return shim.Error(err.Error())
}
//返回成功的标致
return shim.Success(nil)
}
到此源码分析就结束了，具体的内容还需要进一步学习，最后把我们出啊关键的网络给清除了，不影响后续网络的创建。
./byfn.sh -m down -c mychannel
最后
以上就是还单身舞蹈为你收集整理的智能合约代码分析的全部内容，希望文章能够帮你解决智能合约代码分析所遇到的程序开发问题。
如果觉得靠谱客网站的内容还不错，欢迎将靠谱客网站推荐给程序员好友。
本图文内容来源于网友提供，作为学习参考使用，或来自网络收集整理，版权属于原作者所有。
发表评论 取消回复