helloworld.go

/*
The MIT License (MIT)

Copyright (c) 2016 ALT-F1, We believe in the projects we work on™

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
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furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/

// Package helloworld displays helloworld and the amount of time the invoke method as been called
package main

import (
	"errors"
	"fmt"
	"strconv"

	"github.com/hyperledger/fabric/core/chaincode/shim"
)

var myLogger = logging.MustGetLogger("asset_mgm")

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

// Init is called during Deploy transaction after the container has been
func (t *HelloWorld) Init(stub *shim.ChaincodeStub, function string, args []string) ([]byte, error) {
	myLogger.Debug("HelloWorld Init is called!")

	if len(args) != 0 {
		return nil, errors.New("Incorrect number of arguments. Expecting 0")
	}

	// Set the admin
	// The metadata will contain the certificate of the administrator

	err := stub.PutState("noHelloWorlds", []byte("0"))
	if err != nil {
		return nil, err
	}

	myLogger.Debug("Init HelloWorld...done")

	return nil, nil
}

// Invoke is called for every Invoke transactions. The chaincode may change
// its state variables
func (t *HelloWorld) Invoke(stub *shim.ChaincodeStub, function string, args []string) ([]byte, error) {
	fmt.Printf("HelloWorld in Invoke with function %s!\n", function)
	if function != "invoke" {
		return nil, errors.New("Invalid invoke function name. Expecting \"invoke\"")
	}

	b, err := stub.GetState("noHelloWorlds")
	if err != nil {
		return nil, errors.New("Failed to get state")
	}
	noevts, _ := strconv.Atoi(string(b))

	var theArgs string

	for _, s := range args {
		theArgs = theArgs + "," + s
	}
	fmt.Printf("theArgs: %s ", theArgs)

	err = stub.PutState("noHelloWorlds", []byte(strconv.Itoa(noevts+1)))
	if err != nil {
		return nil, err
	}

	return nil, nil
}

// Query is called for Query transactions. The chaincode may only read
// (but not modify) its state variables and return the result
func (t *HelloWorld) Query(stub *shim.ChaincodeStub, function string, args []string) ([]byte, error) {
	myLogger.Debug("HelloWorld Query is called!\n")
	if function != "query" {
		return nil, errors.New("Invalid query function name. Expecting \"query\"")
	}

	b, err := stub.GetState("noHelloWorlds")
	if err != nil {
		return nil, errors.New("Failed to get state")
	}
	jsonResp := "{\"NoHelloWorlds\":\"" + string(b) + "\"}"
	return []byte(jsonResp), nil
}

func main() {
	myLogger.Debug("HelloWorld Main\n")
	err := shim.Start(new(HelloWorld))
	if err != nil {
		fmt.Printf("Error starting HelloWorld chaincode: %s\n", err)
	}
}