chain3

MOAC JavaScript API version 0.1.23.

This is the MOAC compatible JavaScript API which implements the Generic JSON RPC spec as described in the Chain3.md. It's available on npm as a node module, for bower and component as an embeddable js and as a meteor.js package.

chain3 is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

chain3 is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the LICENSE file for more details.

Updates

• v0.1.23 Update the Buffer allocate methods to avoid the warning messages.
• v0.1.22 Fixed a test in contracTest due to bignumber.js lib, update some dependence pull requests.
• v0.1.21 Fixed the previous bug with lodash.
• v0.1.20 Added admin and txpool RPC methods for VNODE, fixed signature error of zero to support microchain DAPP call functions.
• v0.1.19 Added microchain functions to support microchain DAPP call functions.
• v0.1.18 Adopt the eth-lib to perform the message signing and verifying to avoid signature verifying error.
• v0.1.17 Added RLP encode for non-Hex string before signing and verifying to avoid signature verifying error.
• v0.1.16 Added debug APIs and fixed the unit test error.
• v0.1.15 Added local MOAC sign and verify signature methods.
• v0.1.14 Fixed document errors.
• v0.1.13 Added scs_getBlockList method.
• v0.1.12 Fixed Readme and missing scs_getMicroChainInfo method.
• v0.1.11 Added scs method getMicroChainInfo to work with subchain explorer.
• v0.1.10 Added vnode and scs methods to work with MicroChains.
• v0.1.9 Added new method to get ip for local node.
• v0.1.8 Moved git repository to https://github.com/MOACChain/chain3 and fixed some bugs.
• v0.1.7 Fixed uneven signature R & S.
• v0.1.6 A complete package with all tests.
• v0.1.4 First compatible version with MOAC chain.

Some of the methods require running a local MOAC node to use this library. To use vnode methods, need to enable the vnode APIs in MOAC node by: --rpc --rpcport "8545" --rpcapi "chain3,mc,net,vnode"

To use scs methods, need to enable the SCS RPC ports by: --rpc

More information is in Chain3.md or MOAC wiki.

Installation

Node.js

npm install chain3

As Browser module

Bower

bower install chain3

Meteor.js

meteor add moaclib:chain3

• Include chain3.min.js in your html file. (not required for the meteor package)

Usage

Use the chain3 object directly from global namespace:

var Chain3 = require('chain3');
var chain3 = new Chain3();
console.log(chain3); // {mc: .., net: ...} // it's here!

Set a provider (HttpProvider) with VNODE:

if (typeof chain3 !== 'undefined') {
  chain3 = new Chain3(chain3.currentProvider);
} else {
  // set the provider you want from Chain3.providers
  chain3 = new Chain3(new Chain3.providers.HttpProvider("http://localhost:8545"));
}

Set a provider (HttpProvider using HTTP Basic Authentication)

chain3.setProvider(new chain3.providers.HttpProvider('http://host.url', 0, BasicAuthUsername, BasicAuthPassword));

There you go, now you can use it:

var coinbase = chain3.mc.coinbase;
var balance = chain3.mc.getBalance(coinbase);

To work with SCS servers, need to enable the rpc port on SCS monitors and set the scsProvider for chain3.

if (typeof chain3 !== 'undefined') {
  chain3 = new Chain3(chain3.currentProvider);
} else {
  // set the provider you want from Chain3.providers
  chain3 = new Chain3(new Chain3.providers.HttpProvider("http://localhost:8545"));
  chain3.setScsProvider(new chain3.providers.HttpProvider('http://localhost:8548'));
}

After set the SCS monitor, now you can use it:

mclist=chain3.scs.getMicroChainList();
console.log("SCS MicroChain List:", mclist);

console.log("MicroChain state:", chain3.scs.getDappState(mclist[0]));
console.log("MicroChain blockNumber:", chain3.scs.getBlockNumber(mclist[0]));

More examples are under the example directory

Contribute!

Requirements

• Node.js
• npm

sudo apt-get update
sudo apt-get install nodejs
sudo apt-get install npm
sudo apt-get install nodejs-legacy

Building (gulp)

Require install gulp (https://gulpjs.com/) in the system:

npm run-script build

Testing (mocha)

Test all cases. May need to install package mocha first.

mocha

Test a singe function.

mocha test/chain3.mc.coinbase.js 

Some examples

send_mc

Example codes to send moac through signed transaction.

var rawTx = {
      from: src.addr,
      nonce: chain3.intToHex(txcount),
      gasPrice: chain3.intToHex(2000000000),
      gasLimit: chain3.intToHex(2000),
      to: '0xf1f5b7a35dff6400af7ab3ea54e4e637059ef909',
      value: chain3.intToHex(chain3.toSha(value, 'mc')), 
      data: '0x00',
      chainId: chainid
    }

var cmd1 = chain3.signTransaction(rawTx, src["key"]);

chain3.mc.sendRawTransaction(cmd1, function(err, hash) {
    if (!err){
	console.log("Succeed!: ", hash);
	return hash;
    }else{
	console.log("Chain3 error:", err.message);
	return err.message;
    }
});

contract_deploy

Deploy a contract through chain3 RPC calls. This example requires install solc solc

build a web server to access the MOAC network using this API library.

sign and verify the signatures

Example codes to sign a message using MOAC network and verify the signature.

  // Connect with the MOAC network
  chain3.setProvider(new chain3.providers.HttpProvider('http://gateway.moac.io/mainnet'));

  if (!chain3.isConnected()){
      console.log("Chain3 RPC is not connected!");
     return;
  }

  // Hash the message
  let sha3Msg = chain3.sha3("HELLO MOAC!");

  // Unlock the account 'tacct.addr' before signing
  let signedData = chain3.mc.sign(tacct.addr, sha3Msg);

  // or you can call the local function to get the same result, but require a private key
  let signedData = chain3.signMcMessage(sha3Msg,tacct.key);

  // Verify the signature with the message and the address
  console.log("Verify:", chain3.verifyMcSignature(sha3Msg, signedData, tacct.addr))；

Accounts use the following library for generating private key.

browserify-cryptojs v0.3.1