HPB 主网接入最佳实践之JS版

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2023-12-01

1、开始准备

1.1 学习门槛

  • 熟悉JavaScript的基本语法和使用
  • 熟悉Git版本管理的基本语法和使用
  • 熟悉区块链的基本原理
  • HPB主网如何介入请前往https://www.hpb.io/client了解

1.2 源码地址

https://github.com/loglos/web3.git

2、HPB JavaScript API使用说明

This is the HPB compatible JavaScript API which implements the Generic JSON RPC spec.

You need to run a local HPB node to use this library.

2.1 Table of Contents

As a Browser module

CDN

<script type="text/javascript" src="https://hpb.io/web_hpb.min.js"></script>
  • Include web3_hpb.min.js in your html file.

2.2 Usage

Use the web3_hpb object directly from the global namespace:

var Web3ForHpb = require('web3_hpb');
var web3Hpb = new Web3ForHpb();
console.log(web3Hpb); //{ hpb:..., shh:... }

Set a provider (HttpProvider):

// Set the provider you want from Web3.providers
web3 = new Web3(new Web3.providers.HttpProvider("http://localhost:8545"));

There you go, now you can use it:

var coinbase = web3Hpb.hpb.coinbase;
var balance = web3Hpb.hpb.getBalance(coinbase);

3、HPB JavaScript API examples

3.1 balance

https://github.com/yanranxiaoxiaoshu/web3/blob/master/web3_hpb/example/balance.html

<!DOCTYPE html>
<html>

<head>
    <script type="text/javascript" src="../node_modules/bignumber.js/bignumber.min.js"></script>
    <script type="text/javascript" src="../dist/web3_hpb-light.js"></script>
    <script type="text/javascript">

        var web3_hpb = require('web3_hpb');
        var web3_hpb = new web3_hpb();
        web3_hpb.setProvider(new web3_hpb.providers.HttpProvider());

        function watchBalance() {
            var coinbase = web3_hpb.hpb.coinbase;

            var originalBalance = web3_hpb.hpb.getBalance(coinbase).toNumber();
            document.getElementById('coinbase').innerText = 'coinbase: ' + coinbase;
            document.getElementById('original').innerText = ' original balance: ' + originalBalance + '    watching...';

            web3_hpb.hpb.filter('latest').watch(function () {
                var currentBalance = web3_hpb.hpb.getBalance(coinbase).toNumber();
                document.getElementById("current").innerText = 'current: ' + currentBalance;
                document.getElementById("diff").innerText = 'diff:    ' + (currentBalance - originalBalance);
            });
        }

    </script>
</head>

<body>
    <h1>coinbase balance</h1>
    <button type="button" onClick="watchBalance();">watch balance</button>
    <div></div>
    <div id="coinbase"></div>
    <div id="original"></div>
    <div id="current"></div>
    <div id="diff"></div>
</body>

</html>

3.2 contract

<!DOCTYPE html>
<html>

<head>
<script type="text/javascript" src="../dist/web3_hpb.js"></script>
<script type="text/javascript">
    var web3_hpb = require('web3_hpb');
    var web3_hpb = new web3_hpb();
    web3_hpb.setProvider(new web3_hpb.providers.HttpProvider("http://localhost:8545"));
    // solidity code code
    var source = "" +
    "pragma solidity ^0.4.6;" +
    "contract test {\n" +
    "   function multiply(uint a) constant returns(uint d) {\n" +
    "       return a * 7;\n" +
    "   }\n" +
    "}\n";
    var compiled = web3_hpb.hpb.compile.solidity(source);
    var code = compiled.code;
    // contract json abi, this is autogenerated using solc CLI
    var abi = compiled.info.abiDefinition;
    var myContract;
    function createExampleContract() {
        // hide create button
        document.getElementById('create').style.visibility = 'hidden'; 
        document.getElementById('code').innerText = code;
        // let's assume that coinbase is our account
        web3_hpb.hpb.defaultAccount = web3_hpb.hpb.coinbase;
        // create contract
        document.getElementById('status').innerText = "transaction sent, waiting for confirmation";
        web3_hpb.hpb.contract(abi).new({data: code}, function (err, contract) {
            if(err) {
                console.error(err);
                return;
            // callback fires twice, we only want the second call when the contract is deployed
            } else if(contract.address){
                myContract = contract;
                console.log('address: ' + myContract.address);
                document.getElementById('status').innerText = 'Mined!';
                document.getElementById('call').style.visibility = 'visible';
            }
        });
    }
    function callExampleContract() {
        // this should be generated by hpber
        var param = parseInt(document.getElementById('value').value);
        // call the contract
        var res = myContract.multiply(param);
        document.getElementById('result').innerText = res.toString(10);
    }
</script>
</head>
<body>
    <h1>contract</h1>
    <div id="code"></div> 
    <div id="status"></div>
    <div id='create'>
        <button type="button" onClick="createExampleContract();">create example contract</button>
    </div>
    <div id='call' style='visibility: hidden;'>
        <input type="number" id="value" onkeyup='callExampleContract()'></input>
    </div>
    <div id="result"></div>
</body>
</html>

3.3 contract_array

<!DOCTYPE html>
<html>

<head>
<script type="text/javascript" src="../dist/web3_hpb.js"></script>
<script type="text/javascript">
    var web3_hpb = require('web3_hpb');
    var web3_hpb = new web3_hpb();
    web3_hpb.setProvider(new web3_hpb.providers.HttpProvider("http://localhost:8545"));
    // solidity code code
    var source = "" +
    "pragma solidity ^0.4.6;" +
    "contract test {\n" +
    "   function take(uint[] a, uint b) constant returns(uint d) {\n" +
    "       return a[b];\n" +
    "   }\n" +
    "}\n";
    var compiled = web3_hpb.hpb.compile.solidity(source);
    var code = compiled.code;
    // contract json abi, this is autogenerated using solc CLI
    var abi = compiled.info.abiDefinition;
    var myContract;
    function createExampleContract() {
        // hide create button
        document.getElementById('create').style.visibility = 'hidden'; 
        document.getElementById('code').innerText = code;
        // let's assume that coinbase is our account
        web3_hpb.hpb.defaultAccount = web3_hpb.hpb.coinbase;
        // create contract
        document.getElementById('status').innerText = "transaction sent, waiting for confirmation";
        web3_hpb.hpb.contract(abi).new({data: code}, function (err, contract) {
            if (err) {
                console.error(err);
                return;
            // callback fires twice, we only want the second call when the contract is deployed
            } else if(contract.address){
                myContract = contract;
                console.log('address: ' + myContract.address);
                document.getElementById('status').innerText = 'Mined!';
                document.getElementById('call').style.visibility = 'visible';
            }
        });
    }
    function callExampleContract() {
        // this should be generated by hpber
        var param = parseInt(document.getElementById('value').value);
        // call the contract
        var res = myContract.take([0,6,5,2,1,5,6], param);
        document.getElementById('result').innerText = res.toString(10);
    }
</script>
</head>
<body>
    <h1>contract</h1>
    <div id="code"></div> 
    <div id="status"></div>
    <div id='create'>
        <button type="button" onClick="createExampleContract();">create example contract</button>
    </div>
    <div id='call' style='visibility: hidden;'>
        <div>var array = [0,6,5,2,1,5,6];</div>
        <div>var x = array[
            <input type="number" id="value" onkeyup='callExampleContract()'></input>
        ];
        </div>
    </div>
    <div id="result"></div>
</body>
</html>

3.4 event_inc

<!DOCTYPE html>
<html>
    <head>
    <script type="text/javascript" src="../dist/web3_hpb.js"></script>
    <script type="text/javascript">
        var web3_hpb = require('web3_hpb');
        var web3_hpb = new web3_hpb();
        web3_hpb.setProvider(new web3_hpb.providers.HttpProvider('http://localhost:8545'));
        var source = "" +
        "pragma solidity ^0.4.6;" +
        "contract Contract { " +
        "   event Incremented(bool indexed odd, uint x); " +
        "   function Contract() { " +
        "        x = 70; " +
        "    } " +
        "    function inc() { " +
        "        ++x; " +
        "        Incremented(x % 2 == 1, x); " +
        "    } " +
        "    uint x; " +
        "}";
        var compiled = web3_hpb.hpb.compile.solidity(source);
        var code = compiled.code;
        var abi = compiled.info.abiDefinition;
        var address;
        var contract;
        var inc;
        var update = function (err, x) {
            document.getElementById('result').textContent = JSON.stringify(x, null, 2);
        };

        var createContract = function () {
            // let's assume that we have a private key to coinbase ;)
            web3_hpb.hpb.defaultAccount = web3_hpb.hpb.coinbase;

            document.getElementById('create').style.visibility = 'hidden';
            document.getElementById('status').innerText = "transaction sent, waiting for confirmation";
            web3_hpb.hpb.contract(abi).new({data: code}, function (err, c) {
                if (err) {
                    console.error(err);
                    return;
                // callback fires twice, we only want the second call when the contract is deployed
                } else if(c.address){
                    contract = c;
                    console.log('address: ' + contract.address);
                    document.getElementById('status').innerText = 'Mined!';
                    document.getElementById('call').style.visibility = 'visible';
                    inc = contract.Incremented({odd: true}, update);
                }
            });
        };
        var counter = 0;
        var callContract = function () {
            counter++;
            var all = 70 + counter;
            document.getElementById('count').innerText = 'Transaction sent ' + counter + ' times. ' + 
                'Expected x value is: ' + (all - (all % 2 ? 0 : 1)) + ' ' +
                'Waiting for the blocks to be mined...';

            contract.inc();
        };
    </script>
    </head>

    <body>
        <div id="status"></div>
        <div>
            <button id="create" type="button" onClick="createContract();">create contract</button>
        </div>
        <div>
            <button id="call" style="visibility: hidden;" type="button" onClick="callContract();">test1</button>
        </div>
        <div id='count'></div>
        <div id="result">
        </div>
    </body>

3.5 icap

<!DOCTYPE html>
<html>

<head>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">
<script src="https://code.jquery.com/jquery-2.1.4.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script>
<script type="text/javascript" src="../dist/web3_hpb.js"></script>
<script type="text/javascript">
    var web3_hpb = require('web3_hpb');
    var web3_hpb = new web3_hpb();
    var BigNumber = require('bignumber.js');
    web3_hpb.setProvider(new web3_hpb.providers.HttpProvider("http://localhost:8545"));
    var from = web3_hpb.hpb.coinbase;
    web3_hpb.hpb.defaultAccount = from;
    var nameregAbi = [
        {"constant":true,"inputs":[{"name":"_owner","type":"address"}],"name":"name","outputs":[{"name":"o_name","type":"bytes32"}],"type":"function"},
        {"constant":true,"inputs":[{"name":"_name","type":"bytes32"}],"name":"owner","outputs":[{"name":"","type":"address"}],"type":"function"},
        {"constant":true,"inputs":[{"name":"_name","type":"bytes32"}],"name":"content","outputs":[{"name":"","type":"bytes32"}],"type":"function"},
        {"constant":true,"inputs":[{"name":"_name","type":"bytes32"}],"name":"addr","outputs":[{"name":"","type":"address"}],"type":"function"},
        {"constant":false,"inputs":[{"name":"_name","type":"bytes32"}],"name":"reserve","outputs":[],"type":"function"},
        {"constant":true,"inputs":[{"name":"_name","type":"bytes32"}],"name":"subRegistrar","outputs":[{"name":"o_subRegistrar","type":"address"}],"type":"function"},
        {"constant":false,"inputs":[{"name":"_name","type":"bytes32"},{"name":"_newOwner","type":"address"}],"name":"transfer","outputs":[],"type":"function"},
        {"constant":false,"inputs":[{"name":"_name","type":"bytes32"},{"name":"_registrar","type":"address"}],"name":"setSubRegistrar","outputs":[],"type":"function"},
        {"constant":false,"inputs":[],"name":"Registrar","outputs":[],"type":"function"},
        {"constant":false,"inputs":[{"name":"_name","type":"bytes32"},{"name":"_a","type":"address"},{"name":"_primary","type":"bool"}],"name":"setAddress","outputs":[],"type":"function"},
        {"constant":false,"inputs":[{"name":"_name","type":"bytes32"},{"name":"_content","type":"bytes32"}],"name":"setContent","outputs":[],"type":"function"},
        {"constant":false,"inputs":[{"name":"_name","type":"bytes32"}],"name":"disown","outputs":[],"type":"function"},
        {"constant":true,"inputs":[{"name":"_name","type":"bytes32"}],"name":"register","outputs":[{"name":"","type":"address"}],"type":"function"},
        {"anonymous":false,"inputs":[{"indexed":true,"name":"name","type":"bytes32"}],"name":"Changed","type":"event"},
        {"anonymous":false,"inputs":[{"indexed":true,"name":"name","type":"bytes32"},{"indexed":true,"name":"addr","type":"address"}],"name":"PrimaryChanged","type":"event"}
    ];
    var depositAbi = [{"constant":false,"inputs":[{"name":"name","type":"bytes32"}],"name":"deposit","outputs":[],"type":"function"}];
    var Namereg = web3_hpb.hpb.contract(nameregAbi);
    var Deposit = web3_hpb.hpb.contract(depositAbi);
    var namereg = web3_hpb.hpb.ibanNamereg;
    var deposit; 
    var iban;
    function validateNamereg() {
        var address = document.getElementById('namereg').value;
        var ok = web3_hpb.isAddress(address) || address === 'default';
        if (ok) {
            namereg = address === 'default' ? web3_hpb.hpb.ibanNamereg : Namereg.at(address);
            document.getElementById('nameregValidation').innerText = 'ok!';
        } else {
            document.getElementById('nameregValidation').innerText = 'namereg address is incorrect!';
        }
        return ok;
    };
    function onNameregKeyUp() {
        updateIBAN(validateNamereg());
        onExchangeKeyUp();
    };

    function validateExchange() {
        var exchange = document.getElementById('exchange').value;
        var ok = /^[0-9A-Z]{4}$/.test(exchange);
        if (ok) {
            var address = namereg.addr(exchange);
            deposit = Deposit.at(address);
            document.getElementById('exchangeValidation').innerText = 'ok! address of exchange: ' + address;
        } else {
            document.getElementById('exchangeValidation').innerText = 'exchange id is incorrect';
        }
        return ok;
    };
    function onExchangeKeyUp() {
        updateIBAN(validateExchange());
    };
    function validateClient() {
        var client = document.getElementById('client').value;
        var ok = /^[0-9A-Z]{9}$/.test(client);
        if (ok) {
            document.getElementById('clientValidation').innerText = 'ok!';
        } else {
            document.getElementById('clientValidation').innerText = 'client id is incorrect';
        }
        return ok;
    };
    function onClientKeyUp() {
        updateIBAN(validateClient());
    };
    function validateValue() {
        try {
            var value = document.getElementById('value').value;
            var bnValue = new BigNumber(value);
            document.getElementById('valueValidation').innerText = bnValue.toString(10);
            return true;
        } catch (err) {
            document.getElementById('valueValidation').innerText = 'Value is incorrect, cannot parse';
            return false;
        }
    };
    function onValueKeyUp() {
        validateValue();
    };
    function validateIBAN() {
        if (!iban.isValid()) {
            return document.getElementById('ibanValidation').innerText = ' - IBAN number is incorrect';
        }
        document.getElementById('ibanValidation').innerText = ' - IBAN number correct';
    };
    function updateIBAN(ok) {
        var exchangeId = document.getElementById('exchange').value;
        var clientId = document.getElementById('client').value; 
        iban = web3_hpb.hpb.iban.createIndirect({
            institution: exchangeId,
            identifier: clientId
        });
        document.getElementById('iban').innerText = iban.toString();
        validateIBAN();
    };
    function transfer() {
        var value = new BigNumber(document.getElementById('value').value);
        var exchange = document.getElementById('exchange').value;
        var client = document.getElementById('client').value;
        deposit.deposit(web3_hpb.fromAscii(client), {value: value});
        displayTransfer("deposited client's " + client + " funds " + value.toString(10) + " to exchange " + exchange);
    };
    function displayTransfer(text) {
        var node = document.createElement('li');
        var textnode = document.createTextNode(text);
        node.appendChild(textnode);
        document.getElementById('transfers').appendChild(node);
    }

</script>
</head>
<body>
    <div class="col-lg-12">
        <i>This page expects ghpb with JSON-RPC running at port 8545</i>
        <div class="page-header">
            <h1>ICAP transfer</h1>
        </div>
        <div class="col-lg-6">
            <div class="well">
                <legend class="lead">namereg address</legend>
                <small>eg. 0x436474facc88948696b371052a1befb801f003ca or 'default')</small>
                <div class="form-group">
                    <input class="form-control" type="text" id="namereg" onkeyup='onNameregKeyUp()' value="default"></input>
                    <text id="nameregValidation"></text>
                </div>

                <legend class="lead">exchange identifier</legend>
                <small>eg. WYWY</small>
                <div class="form-group">
                    <input class="form-control" type="text" id="exchange" onkeyup='onExchangeKeyUp()'></input>
                    <text id="exchangeValidation"></text>
                </div>

                <legend class="lead">client identifier</legend>
                <small>eg. GAVOFYORK</small>
                <div class="form-group">
                    <input class="form-control" type="text" id="client" onkeyup='onClientKeyUp()'></input>
                    <text id="clientValidation"></text>
                </div>

                <legend class="lead">value</legend>
                <small>eg. 100</small>
                <div class="form-group">
                    <input class="form-control" type="text" id="value" onkeyup='onValueKeyUp()'></input>
                    <text id="valueValidation"></text>
                </div>

                <legend class="lead">IBAN: </legend>
                <div class="form-group">

                    <text id="iban"></text>
                    <text id="ibanValidation"></text>
                </div>
                <div>
                    <button class="btn btn-default" id="transfer" type="button" onClick="transfer()">Transfer!</button>
                    <text id="transferValidation"></text>
                </div>
            </div>
        </div>
        <div class="col-lg-6">
            <div class="well">
                <div>
                    <legend class="lead">transfers</legend>
                </div>
                <div>
                    <ul id='transfers'></ul>
                </div>
            </div>
        </div>
    </div>
</body>
</html>

3.6 namereg

<!DOCTYPE html>
<html>

<head>
<script type="text/javascript" src="../dist/web3_hpb.js"></script>
<script type="text/javascript">
    var web3_hpb = require('web3_hpb');
    var web3_hpb = new web3_hpb();
    web3_hpb.setProvider(new web3_hpb.providers.HttpProvider("http://localhost:8545"));
    var from = web3_hpb.hpb.coinbase;
    web3_hpb.hpb.defaultAccount = from;
    window.onload = function () {
        var filter = web3_hpb.hpb.namereg().Changed();
        filter.watch(function (err, event) {
            // live update all fields
            onAddressKeyUp();
            onNameKeyUp();
            onRegisterOwnerKeyUp();
        });
    };
    function registerOwner() {
        var name = document.getElementById('registerOwner').value;
        web3_hpb.hpb.namereg().reserve(name);
        document.getElementById('nameAvailability').innerText += ' Registering name in progress, please wait...';
    };

    function changeAddress() {
        var name = document.getElementById('registerOwner').value;
        var address = document.getElementById('newAddress').value;
        web3_hpb.hpb.namereg().setAddress(name, address, true);
        document.getElementById('currentAddress').innerText += ' Changing address in progress. Please wait.';
    };
    function onRegisterOwnerKeyUp() {
        var name = document.getElementById('registerOwner').value;
        var owner = web3_hpb.hpb.namereg().owner(name)
        document.getElementById('currentAddress').innerText = web3_hpb.hpb.namereg().addr(name);
        if (owner !== '0x0000000000000000000000000000000000000000') {
            if (owner === from) {
                document.getElementById('nameAvailability').innerText = "This name is already owned by you " + owner;
            } else {
                document.getElementById('nameAvailability').innerText = "This name is not available. It's already registered by " + owner;
            }
            return;
        }
        document.getElementById('nameAvailability').innerText = "This name is available. You can register it.";
    };
    function onAddressKeyUp() {
        var address = document.getElementById('address').value;
        document.getElementById('nameOf').innerText = web3_hpb.hpb.namereg().name(address);
    };

    function onNameKeyUp() {
        var name = document.getElementById('name').value;
        document.getElementById('addressOf').innerText = web3_hpb.hpb.namereg().addr(name);
    };
</script>
</head>
<body>
    <i>This example shows only part of namereg functionalities. Namereg contract is available <a href="https://github.com/hpber/dapp-bin/blob/master/GlobalRegistrar/contract.sol">here</a>
    </i>
    <h1>Namereg</h1>
    <h3>Search for name</h3>
    <div>
        <text>Address: </text>
        <input type="text" id="address" onkeyup='onAddressKeyUp()'></input>
        <text>Name: </text>
        <text id="nameOf"></text>
    </div>
    <h3>Search for address</h3>
    <div>
        <text>Name: </text>
        <input type="text" id="name" onkeyup='onNameKeyUp()'></input>
        <text>Address: </text>
        <text id="addressOf"></text>
    </div>
    <h3>Register name</h3>
    <div>
        <text>Check if name is available: </text>
        <input type="text" id="registerOwner" onkeyup='onRegisterOwnerKeyUp()'></input>
        <text id='nameAvailability'></text>
    </div>
    <div>
        <button id="registerOwnerButton" type="button" onClick="registerOwner()">Register!</button>
    </div>
    <h3></h3>
    <i>If you own the name, you can  also change the address it points to</i>
    <div>
        <text>Address: </text>
        <input type="text" id="newAddress"></input>
        <button id="changeAddress" type="button" onClick="changeAddress()">Change address!</button>
        <text>Current address :</text>
        <text id="currentAddress"></text>
    </div>

</body>
</html>

3.7 node-app

#!/usr/bin/env node

var web3_hpb = require('../index.js');
var web3_hpb = new web3_hpb();

web3_hpb.setProvider(new web3_hpb.providers.HttpProvider('http://localhost:8545'));

var coinbase = web3_hpb.hpb.coinbase;
console.log(coinbase);

var balance = web3_hpb.hpb.getBalance(coinbase);
console.log(balance.toString(10));

3.8 signature-verifier

var web3_hpb = require('../index.js');
var hpbURL = ""; 
var defaultAc = ""; 
var defaultAcPWD=""; 
var signatureContractCodeReadable="\n\tcontract SignatureVerifier {\n\t\tfunction verify( bytes32 hash, uint8 v, bytes32 r, bytes32 s) \n"+ 
    "\t\tconstant returns(address returnAddress) {\n \t\t\treturnAddress = ecrecover(hash, v, r, s);\n\t\t}\n\t}\n\n";

var sigContractInstance = null;
var sigContractAddress= ""; 
var sigContractInstance = null;
var strAbi='[{"constant":true,"inputs":[{"name":"hash","type":"bytes32"},{"name":"v","type":"uint8"},{"name":"r","type":"bytes32"},{"name":"s","type":"bytes32"}],"name":"verify","outputs":[{"name":"returnAddress","type":"address"}],"payable":false,"type":"function"}]';
var signMessage=""; 

var hpbweb3_hpb = null;

function setContractAddress(conAddress){
    sigContractAddress = conAddress;
}

function setAccount(act){
    defaultAc = act;
}

function setPassword(pwd){
    defaultAcPWD = pwd;
}

function setHpbURL(url){
    hpbURL = url;
}

function setMessage(msg){
    signMessage = msg;
}

function initializeHpbConnection(){
   if(hpbweb3_hpb!=null && hpbweb3_hpb.isConnected()==true)  {
    return true;
  }

  hpbweb3_hpb = new web3_hpb(new web3_hpb.providers.HttpProvider(hpbURL));

  if(hpbweb3_hpb.isConnected()==true){
      if(defaultAc==''){
        defaultAc=hpbweb3_hpb.hpb.accounts[1];
      }
      return true;
  }

  return false;
}

function unlockAccount(acAddress){
  if(acAddress!=undefined && acAddress!=null){
    var state=hpbweb3_hpb.personal.unlockAccount(defaultAc, defaultAcPWD, 100);
    return state;
  }

  return false; 
}


function initializeContract(){
    initializeHpbConnection();
    if(hpbweb3_hpb.isConnected()==false){
        return;
    }  
    var abi = JSON.parse(strAbi);
    var contract = hpbweb3_hpb.hpb.contract(abi);

    sigContractInstance =  contract.at(sigContractAddress)  
}

function signMessage(message){

    initializeHpbConnection();
    if(hpbweb3_hpb.isConnected()==false){
        return false;
    }

    var state=unlockAccount(defaultAc);

    const msg = new Buffer(message);
    const sig = hpbweb3_hpb.hpb.sign(defaultAc, '0x' + msg.toString('hex'));

    return sig;
}

function verifySignedByAc(message, sig){
    initializeHpbConnection();

    if(hpbweb3_hpb.isConnected()==false){
        return false;
    }
    initializeContract();

    const res = splitSig(sig);

    // Unfortunately Ghpb client adds this line to the message as a prefix while signing
    // So while finding who signed it we need to prefix this part 
    const prefix = new Buffer("\x19Hpb Signed Message:\n");
    const msg = new Buffer(message);
    const prefixedMsg = hpbweb3_hpb.sha3(
    Buffer.concat([prefix, new Buffer(String(msg.length)), msg]).toString('utf8')
    );

    var strPrefixedMsg=prefixedMsg;

    var finalAddress=sigContractInstance.verify.call(strPrefixedMsg, res.v, res.r, '0x'+ res.s);

    return finalAddress;
}

function splitSig(sig) {
  return {
    v: hpbweb3_hpb.toDecimal('0x' + sig.slice(130, 132)),
    r: sig.slice(0, 66),
    s: sig.slice(66, 130)
  }

}

function sign(){
    var message = document.getElementById('txtMessage').value;
    var signMsg = signMessage(message);
    document.getElementById('dvSig').innerText = signMsg;
}

function verify(){
    var message = document.getElementById('txtMessage').value;
    var actAddr = verifySignedByAc(message, document.getElementById('dvSig').innerText);
    document.getElementById('dvSignedBy').innerText = actAddr;
}


function execute(){
    console.log("\n\n**********************************************************************");
    console.log("Steps to Run");
    console.log("**********************************************************************");
    console.log("1. Deploy the following contract in your hpber environment");
    console.log(signatureContractCodeReadable);
    console.log("2. Set the following parameters (i.e. at the end of the code)");
    console.log("\ta. Hpb URL");
    console.log("\tb. Hpb Account Address");
    console.log("\tc. Hpb Account Passphrase");
    console.log("\td. Signature Contract Address");
    console.log("\te. Message for signing");
    console.log("**********************************************************************");

    if(hpbURL==''){
        console.log("Error: Hpb URL is not specified");
        return;
    }
    if(defaultAc==''){
        console.log("Error: Account Address is not specified");
        return;
    }
    if(defaultAcPWD==''){
        console.log("Error: Account password is not specified");
        return;
    }
    if(sigContractAddress==''){
        console.log("Error: Signature Contract Address is not specified");
        return;
    }
    if(signMessage==''){
        console.log("Error: Message for signing is not specified");
        return;
    }


    console.log("Following parameters applied");
    console.log("\ta. Hpb URL                  :",hpbURL);
    console.log("\tb. Hpb Account Address      :",defaultAc);
    console.log("\tc. Hpb Account Passphrase   :",defaultAcPWD);
    console.log("\td. Signature Contract Address    :",sigContractAddress);
    console.log("\te. Message for signing           :",signMessage);

    console.log("**********************************************************************");
    console.log("Result");
    console.log("**********************************************************************");

    var sig=signMessage(signMessage);
    console.log("Signature");
    console.log(sig);

    var addr=verifySignedByAc(signMessage, sig);
    console.log("Signed By");
    console.log(addr);

    console.log("**********************************************************************");
    console.log("Exit");
    console.log("**********************************************************************");
}

// Please uncomment the below listed three lines of code and provide the required values

// Value 1- Please provide the hpber account address which you want to use to perform the operation
//setAccount('<Provide the account address>');

// Value 2- Please provide the password of the accound to be used 
//setPassword('<Provide the password>');

// Value 3- Please update the address of the contract after deployment
// The contract code is made available at the top under signatureContractCodeReadable variable
// Please deploy the contract and update the contract address here
//setContractAddress('<Provide the deployed contract address>');

// Value 4- If required please update with a different message
setHpbURL('http://localhost:8545');

// Value 5- If required please update with a Hpb URL
setMessage('This the test sign message');


execute();