Chaincode function to display struct values - go

Question

I'm trying to write a simple chaincode that uses a structure to store customer details. I have one setDetails func that works fine. I wish to write another getDetails func that takes UID as arguement and prints the details of the customer with that UID. Need Help!
package main
import (
"errors"
"fmt"
"github.com/hyperledger/fabric/core/chaincode/shim"
)
type Customer struct {
UID string
Name string
Address struct {
StreetNo string
Country string
}
}
type SimpleChaincode struct {
}
func (t *SimpleChaincode) Init(stub shim.ChaincodeStubInterface) ([]byte, error) {
fmt.Printf("initialization done!!!")
fmt.Printf("initialization done!!!")
return nil, nil
}
func (t *SimpleChaincode) setDetails(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
if len(args) < 3 {
return nil, errors.New("insert Into Table failed. Must include 3 column values")
}
customer := &Customer{}
customer.UID = args[0]
customer.Name = args[1]
customer.Address.Country = args[2]
return nil, nil
}
func (t *SimpleChaincode) getDetails(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
//wish to print all details of an particular customer corresponding to the UID
return nil, nil
}
func (t *SimpleChaincode) Invoke(stub shim.ChaincodeStubInterface) ([]byte, error) {
function, args := stub.GetFunctionAndParameters()
fmt.Printf("Inside Invoke %s", function)
if function == "setDetails" {
return t.setDetails(stub, args)
} else if function == "getDetails" {
return t.getDetails(stub, args)
}
return nil, errors.New("Invalid invoke function name. Expecting \"query\"")
}
func main() {
err := shim.Start(new(SimpleChaincode))
if err != nil {
fmt.Printf("Error starting Simple chaincode: %s", err)
}
}

Answer 1

I didn't know about Hyperledger until now, but after a look at the github documentation, I get you would use stub.PutState to store your customer information, then later use stub.GetState to get it back.
As both methods request a byte slice, my guess would be something along these lines:
func (t *SimpleChaincode) setDetails(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
if len(args) < 3 {
return nil, errors.New("insert Into Table failed. Must include 3 column values")
}
customer := &Customer{}
customer.UID = args[0]
customer.Name = args[1]
customer.Address.Country = args[2]
raw, err := json.Marshal(customer)
if err != nil {
return nil, err
}
err := stub.PuState(customer.UID, raw)
if err != nil {
return nil, err
}
return nil, nil
}
func (t *SimpleChaincode) getDetails(stub shim.ChaincodeStubInterface, args []string) ([]byte, error) {
if len(args) != 1 {
return nil, errors.New("Incorrect number of arguments. Expecting name of the key to query")
}
return stub.GetState(args[0])
}