【发布时间】：2018-01-15 03:57:43
【问题描述】：
我正在学习如何使用 Hyperledger Fabric DLT 框架。
我正在构建一个应用程序，允许 金枪鱼 的卖家以折扣价与买家进行交易，而不会影响卖家向其他买家出售的标记价格。
问题：但是每次执行代码时都会抛出此消息
2018-01-14 18:45:11.292 EST [shim] SetupChaincodeLogging -> INFO 001 Chaincode log level not provided; defaulting to: INFO
2018-01-14 18:45:11.292 EST [shim] SetupChaincodeLogging -> INFO 002 Chaincode (build level: ) starting up ...
这是我每次运行代码时不断遇到的错误：
Error creating new Smart Contract: Error chaincode id not providedeloiim:fabric_
这是我创建的代码
package main
import ( "github.com/hyperledger/fabric/core/chaincode/shim"; sc"github.com/hyperledger/fabric/protos/peer"; "bytes"; "encoding/json"; "strconv"; "fmt"; )
type SmartContract struct {
}
type Tuna struct {
TxID int `json:"txid"`
Container string `json:"container"`
Timestamp string `json:"timestamp"`
Location string `json:"location"`
Owner string `json:"owner"`
}
changeTunaHolder - 当金枪鱼被传递到供应链中的不同方时，世界状态中的数据可以更新为谁拥有。 changeTunaHolder 方法接受 2 个参数，金枪鱼 id 和新持有者名称。
我怀疑这个错误与 changeTunaHolder 方法有关，因为它需要 id 和 Owner 字段
func (S_ *SmartContract) changeTunaHolder(APIstub shim.ChaincodeStubInterface, parameters []string) sc.Response {
if len(parameters) != 2 {
return shim.Error("Incorrect number of arguments. Expecting 2")
}
tunaAsBytes, _ := APIstub.GetState(parameters[0])
if tunaAsBytes == nil {
return shim.Error("Could not locate tuna")
}
TUNA := Tuna{}
json.Unmarshal(tunaAsBytes, &TUNA)
// Normally check that the specified argument is a valid holder of tuna
// we are skipping this check for this example
TUNA.Owner = parameters[1]
tunaAsBytes, _ = json.Marshal(TUNA)
_error := APIstub.PutState(parameters[0], tunaAsBytes)
if _error != nil {
return shim.Error(fmt.Sprintf("Failed to change tuna holder: %s", parameters[0]))
}
return shim.Success(nil)
}
Init METHOD - 在此代码尝试检索请求的智能合约函数和参数
func (S_ *SmartContract) Init(APIstub shim.ChaincodeStubInterface) sc.Response {
return shim.Success(nil)
}
func (S_ *SmartContract ) Invoke(APIstub shim.ChaincodeStubInterface) sc.Response {
function, parameters := APIstub.GetFunctionAndParameters()
if function == "queryTuna" {
return S_.queryTuna(APIstub, parameters)
} else if function == "initLedger"{
return S_.initLedger(APIstub)
} else if function == "recordTuna" {
return S_.recordTuna(APIstub, parameters)
} else if function == "changeTunaHolder" {
return S_.changeTunaHolder(APIstub, parameters)
}
return shim.Error("Invalid Smart Contract function name.")
}
queryTuna - 渔民、监管者或餐馆老板将使用 queryTuna 方法来查看特定金枪鱼的记录。它需要一个参数 - 有问题的金枪鱼的关键。
func (S_ *SmartContract) queryTuna(APIstub shim.ChaincodeStubInterface, parameters []string) sc.Response {
if len(parameters) != 1{
return shim.Error("Incorrect number of arguments. Expecting 1")
}
tunaAsBytes, _ := APIstub.GetState(parameters[0])
if tunaAsBytes == nil {
return shim.Error("Could not locate tuna")
}
return shim.Success(tunaAsBytes)
}
initLedger - initLedger 方法会将测试数据添加到我们的网络中。
func (S_ *SmartContract) initLedger(APIstub shim.ChaincodeStubInterface) sc.Response{
TUNA := []Tuna {
Tuna{TxID: 1,Container: "923F", Location: "67.0006, -70.5476", Timestamp: "1504054225", Owner: "Miriam"},
Tuna{TxID: 2,Container: "M83T", Location: "91.2395, -49.4594", Timestamp: "1504057825", Owner: "Dave"},
Tuna{TxID: 3,Container: "T012", Location: "58.0148, 59.01391", Timestamp: "1493517025", Owner: "Igor"},
Tuna{TxID: 4,Container: "P490", Location: "-45.0945, 0.7949", Timestamp: "1496105425", Owner: "Amalea"},
Tuna{TxID: 5,Container: "S439", Location: "-107.6043, 19.5003", Timestamp: "1493512301", Owner: "Rafa"},
Tuna{TxID: 6,Container: "J205", Location: "-155.2304, -15.8723", Timestamp: "1494117101", Owner: "Shen"},
Tuna{TxID: 7,Container: "S22L", Location: "103.8842, 22.1277", Timestamp: "1496104301", Owner: "Leila"},
Tuna{TxID: 8,Container: "EI89", Location: "-132.3207, -34.0983", Timestamp: "1485066691", Owner: "Yuan"},
Tuna{TxID: 9,Container: "129R", Location: "153.0054, 12.6429", Timestamp: "1485153091", Owner: "Carlo"},
Tuna{TxID: 10,Container: "49W4", Location: "51.9435, 8.2735", Timestamp: "1487745091", Owner: "Fatima"},
}
iter := 0
for iter < len(TUNA) {
println("iter is", iter)
tunaAsBytes, _ := json.Marshal(TUNA[iter])
APIstub.PutState(strconv.Itoa(iter+1), tunaAsBytes)
fmt.Println("ADDED", TUNA[iter])
iter += 1
}
return shim.Success(nil)
}
recordTuna - recordTuna 方法是像 Sarah 这样的渔夫用来记录她捕获的每条金枪鱼的方法。此方法接受五个参数（要保存在分类帐中的属性）。
func (S_ *SmartContract) recordTuna(APIstub shim.ChaincodeStubInterface, parameters[]string) sc.Response {
if len(parameters) != 5 {
return shim.Error("Incorrect number of arguments. Expecting 5")
}
TUNA := Tuna{Container:parameters[1], Location:parameters[2], Timestamp:parameters[3], Owner:parameters[4]}
tunaAsBytes, _:=json.Marshal(TUNA)
_error := APIstub.PutState(parameters[0], tunaAsBytes)
if _error != nil {
return shim.Error(fmt.Sprintf("Failed to record tuna catch: %s", parameters[0]))
}
return shim.Success(nil)
}
queryAllTuna - queryAllTuna 方法允许评估所有记录；在这种情况下，所有 Tuna 记录都添加到分类帐中。此方法不接受任何参数。它将返回一个包含结果的 JSON 字符串。
func (S_ *SmartContract) queryAllTuna(APIstub shim.ChaincodeStubInterface) sc.Response {
init_key := "0"
end_key := "999"
results_iterator, _error := APIstub.GetStateByRange(init_key, end_key)
if _error != nil {
return shim.Error(_error.Error())
}
defer results_iterator.Close()
var buffer bytes.Buffer
buffer.WriteString("[")
b_array_member_already_written := false
for results_iterator.HasNext() {
query_response, _error := results_iterator.Next()
if _error != nil {
return shim.Error(_error.Error())
}
if b_array_member_already_written == true {
buffer.WriteString(",")
}
buffer.WriteString("{\"Key\":")
buffer.WriteString("\"")
buffer.WriteString(query_response.Key)
buffer.WriteString("\"")
buffer.WriteString(", \"Record\":")
buffer.WriteString(string(query_response.Value))
buffer.WriteString("}")
b_array_member_already_written = true
}
buffer.WriteString("]")
fmt.Printf("- queryAllTuna:\n%s\n", buffer.String())
return shim.Success(buffer.Bytes())
}
主要功能
func main() {
_error := shim.Start(new(SmartContract))
if _error != nil {
fmt.Printf("Error creating new Smart Contract: %s", _error)
}
}
【问题讨论】：