Mweb3.js - Web3.js for Metrix

Mweb3 is a library for dApps to interract with the Metrix blockchain. mweb3 communicates to a Metrix node via the provider provided.

https://www.npmjs.com/package/mweb3

Get Started

Run the following in your project folder:

npm install mweb3 --save

Web Dapp Usage

This is example is meant for web dapps who would like to use Mweb3's convenience methods with MetriMask's RPC provider. MetriMask is a Metrix wallet Chrome extension. More details about MetriMask here.

1. Construct Mweb3 instance

If you have MetriMask installed, you will have a window.metrimask object injected in your browser tab. Pass that into Mweb3 as a parameter to set the provider.

const mweb3 = new Mweb3(window.metrimask.rpcProvider);

2. Construct Contract instance

The Contract class is meant for executing sendtocontract or callcontract at a specific contract address with a given ABI.

const contractAddress = 'f7b958eac2bdaca0f225b86d162f263441d23c19';
const contractAbi = [{"constant":false,"inputs":[{"name":"_eventAddress","type":"address"},{"name":"_eventName","type":"bytes32[10]"},{"name":"_eventResultNames","type":"bytes32[10]"},{"name":"_numOfResults","type":"uint8"},{"name":"_lastResultIndex","type":"uint8"},{"name":"_arbitrationEndBlock","type":"uint256"},{"name":"_consensusThreshold","type":"uint256"}],"name":"createDecentralizedOracle","outputs":[{"name":"","type":"address"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[{"name":"_eventAddress","type":"address"},{"name":"_eventName","type":"bytes32[10]"},{"name":"_eventResultNames","type":"bytes32[10]"},{"name":"_numOfResults","type":"uint8"},{"name":"_lastResultIndex","type":"uint8"},{"name":"_arbitrationEndBlock","type":"uint256"},{"name":"_consensusThreshold","type":"uint256"}],"name":"doesDecentralizedOracleExist","outputs":[{"name":"","type":"bool"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"name":"_oracle","type":"address"},{"name":"_eventAddress","type":"address"},{"name":"_eventName","type":"bytes32[10]"},{"name":"_eventResultNames","type":"bytes32[10]"},{"name":"_numOfResults","type":"uint8"},{"name":"_bettingEndBlock","type":"uint256"},{"name":"_resultSettingEndBlock","type":"uint256"},{"name":"_consensusThreshold","type":"uint256"}],"name":"createCentralizedOracle","outputs":[{"name":"","type":"address"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[{"name":"_oracle","type":"address"},{"name":"_eventAddress","type":"address"},{"name":"_eventName","type":"bytes32[10]"},{"name":"_eventResultNames","type":"bytes32[10]"},{"name":"_numOfResults","type":"uint8"},{"name":"_bettingEndBlock","type":"uint256"},{"name":"_resultSettingEndBlock","type":"uint256"},{"name":"_consensusThreshold","type":"uint256"}],"name":"doesCentralizedOracleExist","outputs":[{"name":"","type":"bool"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[{"name":"","type":"bytes32"}],"name":"oracles","outputs":[{"name":"","type":"address"}],"payable":false,"stateMutability":"view","type":"function"},{"inputs":[{"name":"_addressManager","type":"address"}],"payable":false,"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":true,"name":"_contractAddress","type":"address"},{"indexed":true,"name":"_oracle","type":"address"},{"indexed":true,"name":"_eventAddress","type":"address"},{"indexed":false,"name":"_name","type":"bytes32[10]"},{"indexed":false,"name":"_resultNames","type":"bytes32[10]"},{"indexed":false,"name":"_numOfResults","type":"uint8"},{"indexed":false,"name":"_bettingEndBlock","type":"uint256"},{"indexed":false,"name":"_resultSettingEndBlock","type":"uint256"},{"indexed":false,"name":"_consensusThreshold","type":"uint256"}],"name":"CentralizedOracleCreated","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"_contractAddress","type":"address"},{"indexed":true,"name":"_eventAddress","type":"address"},{"indexed":false,"name":"_name","type":"bytes32[10]"},{"indexed":false,"name":"_resultNames","type":"bytes32[10]"},{"indexed":false,"name":"_numOfResults","type":"uint8"},{"indexed":false,"name":"_lastResultIndex","type":"uint8"},{"indexed":false,"name":"_arbitrationEndBlock","type":"uint256"},{"indexed":false,"name":"_consensusThreshold","type":"uint256"}],"name":"DecentralizedOracleCreated","type":"event"}];

// Create a new Contract instance and use the same provider as mweb3
const contract = mweb3.Contract(contractAddress, contractAbi);

3. Get Logged In MetriMask Account

To get the current logged in account in MetriMask, you will have to add an Event Listener to listen to messages sent from MetriMask.

let account;

function onMetriMaskAcctChange(event) {
  if (event.data.message && event.data.message.type == "ACCOUNT_CHANGED") {
    account = event.data.message.payload;

    // You now have the logged in account.
    // account = InpageAccount {
    //   loggedIn: true,
    //   name: "My Wallet", 
    //   network: "TestNet",
    //   address: "mJHp6dUSmDShpEEMmwxqHPo7sFSdydSkPM",
    //   balance: 49.10998413
    // } 

    // You may also get the account from `window.metrimask.account`.
    // account = window.metrimask.account
  }
}
window.addEventListener('message', onMetriMaskAcctChange, false);

4. Execute sendtocontract

The last piece is to execute a sendtocontract on your Contract instance. This will automatically show a MetriMask popup to confirm that you would like to send the transaction.

// Does a sendtocontract call on a function called setResult(uint8)
const tx = await contract.send('setResult', {
  methodArgs: [1],    // Sets the function params
  gasLimit: 1000000,  // Sets the gas limit to 1 million
  senderAddress: account.address,
});
// tx = txid of the transaction

Mweb3Provider

The provider is the link between Mweb3 and the blockchain. A compatible Mweb3 Provider adheres to the following interface:

interface Mweb3Provider: {
  rawCall: (method: string, args: any[]) => Promise; // returns the result of the request
}

Mweb3

Instantiate a new instance of Mweb3:

const { Mweb3 } = require('mweb3');

// Instantiate Mweb3 with HttpProvider
// Pass in the URL of your Metrix node RPC port with auth credentials.
// Default Metrix RPC ports: testnet=33851 mainnet=33831
const mweb3 = new Mweb3('http://mwtrix:metrix@localhost:13889');

// Instantiate Mweb3 with MetriMaskRPCProvider
// MetriMaskRPCProvider is a provider for the MetriMask Wallet Chrome Extension.
// Please note MetriMaskRPCProvider only allows the rawCall() method to be used.
// It is specifically used for `sendtocontract` and `callcontract` only.
const mweb3 = new Mweb3(window.metrimask.rpcProvider);

isConnected()

Checks if you are connected properly to the local Metrix node.

async function isConnected() {
  return await mweb3.isConnected();
}

getHexAddress(address)

Converts a Metrix address to hex format.

async function getHexAddress() {
  return await mweb3.getHexAddress('qKjn4fStBaAtwGiwueJf9qFxgpbAvf1xAy');
}

fromHexAddress(hexAddress)

Converts a hex address to Metrix format.

async function fromHexAddress() {
  return await mweb3.fromHexAddress('17e7888aa7412a735f336d2f6d784caefabb6fa3');
}

getBlockCount()

Gets the current block height of your local Metrix node.

async function getBlockCount() {
  return await mweb3.getBlockCount();
}

getTransaction(txid)

Gets the transaction details of the transaction id.

async function getTransaction(args) {
  const {
    transactionId, // string
  } = args;

  return await mweb3.getTransactionReceipt(transactionId);
}

getTransactionReceipt(txid)

Gets the transaction receipt of the transaction id.

async function getTransactionReceipt(args) {
  const {
    transactionId, // string
  } = args;

  return await mweb3.getTransactionReceipt(transactionId);
}

listUnspent()

Gets the unspent outputs that can be used.

async function listUnspent() {
  return await mweb3.listUnspent();
}

searchLogs(fromBlock, toBlock, addresses, topics, contractMetadata, removeHexPrefix)

Gets the logs given the params on the blockchain.

The contractMetadata param contains the contract names and ABI that you would like to parse. An example of one is:

# contract_metadata.js
module.exports = {
  EventFactory: {
    address: 'd53927df927be7fc51ce8bf8b998cb6611c266b0',
    abi: [{ constant: true, inputs: [{ name: '', type: 'bytes32' }], name: 'topics', outputs: [{ name: '', type: 'address' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: false, inputs: [{ name: '_oracle', type: 'address' }, { name: '_name', type: 'bytes32[10]' }, { name: '_resultNames', type: 'bytes32[10]' }, { name: '_bettingEndBlock', type: 'uint256' }, { name: '_resultSettingEndBlock', type: 'uint256' }], name: 'createTopic', outputs: [{ name: 'topicEvent', type: 'address' }], payable: false, stateMutability: 'nonpayable', type: 'function' }, { constant: true, inputs: [{ name: '_name', type: 'bytes32[10]' }, { name: '_resultNames', type: 'bytes32[10]' }, { name: '_bettingEndBlock', type: 'uint256' }, { name: '_resultSettingEndBlock', type: 'uint256' }], name: 'doesTopicExist', outputs: [{ name: '', type: 'bool' }], payable: false, stateMutability: 'view', type: 'function' }, { inputs: [{ name: '_addressManager', type: 'address' }], payable: false, stateMutability: 'nonpayable', type: 'constructor' }, { anonymous: false, inputs: [{ indexed: true, name: '_topicAddress', type: 'address' }, { indexed: true, name: '_creator', type: 'address' }, { indexed: true, name: '_oracle', type: 'address' }, { indexed: false, name: '_name', type: 'bytes32[10]' }, { indexed: false, name: '_resultNames', type: 'bytes32[10]' }, { indexed: false, name: '_bettingEndBlock', type: 'uint256' }, { indexed: false, name: '_resultSettingEndBlock', type: 'uint256' }], name: 'TopicCreated', type: 'event' }],
  },

  TopicEvent: {
    abi: [{ constant: false, inputs: [{ name: '_resultIndex', type: 'uint8' }, { name: '_sender', type: 'address' }, { name: '_amount', type: 'uint256' }], name: 'voteFromOracle', outputs: [{ name: '', type: 'bool' }], payable: false, stateMutability: 'nonpayable', type: 'function' }, { constant: true, inputs: [], name: 'totalBotValue', outputs: [{ name: '', type: 'uint256' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [{ name: '_oracleIndex', type: 'uint8' }], name: 'getOracle', outputs: [{ name: '', type: 'address' }, { name: '', type: 'bool' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [{ name: '', type: 'address' }], name: 'didWithdraw', outputs: [{ name: '', type: 'bool' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [], name: 'resultSet', outputs: [{ name: '', type: 'bool' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [], name: 'status', outputs: [{ name: '', type: 'uint8' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [], name: 'getFinalResult', outputs: [{ name: '', type: 'uint8' }, { name: '', type: 'string' }, { name: '', type: 'bool' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [{ name: '', type: 'uint256' }], name: 'resultNames', outputs: [{ name: '', type: 'bytes32' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [{ name: '', type: 'uint256' }], name: 'oracles', outputs: [{ name: 'didSetResult', type: 'bool' }, { name: 'oracleAddress', type: 'address' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: false, inputs: [], name: 'finalizeResult', outputs: [{ name: '', type: 'bool' }], payable: false, stateMutability: 'nonpayable', type: 'function' }, { constant: false, inputs: [{ name: '_oracle', type: 'address' }, { name: '_resultIndex', type: 'uint8' }, { name: '_consensusThreshold', type: 'uint256' }], name: 'centralizedOracleSetResult', outputs: [], payable: false, stateMutability: 'nonpayable', type: 'function' }, { constant: true, inputs: [], name: 'totalMetrixValue', outputs: [{ name: '', type: 'uint256' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: false, inputs: [{ name: '_consensusThreshold', type: 'uint256' }], name: 'invalidateOracle', outputs: [], payable: false, stateMutability: 'nonpayable', type: 'function' }, { constant: true, inputs: [], name: 'getBetBalances', outputs: [{ name: '', type: 'uint256[10]' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [], name: 'owner', outputs: [{ name: '', type: 'address' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [], name: 'calculateMetrixContributorWinnings', outputs: [{ name: '', type: 'uint256' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [], name: 'getVoteBalances', outputs: [{ name: '', type: 'uint256[10]' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [], name: 'getTotalVotes', outputs: [{ name: '', type: 'uint256[10]' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: false, inputs: [{ name: '_better', type: 'address' }, { name: '_resultIndex', type: 'uint8' }], name: 'bet', outputs: [], payable: true, stateMutability: 'payable', type: 'function' }, { constant: false, inputs: [{ name: '_resultIndex', type: 'uint8' }, { name: '_currentConsensusThreshold', type: 'uint256' }], name: 'votingOracleSetResult', outputs: [{ name: '', type: 'bool' }], payable: false, stateMutability: 'nonpayable', type: 'function' }, { constant: true, inputs: [], name: 'getTotalBets', outputs: [{ name: '', type: 'uint256[10]' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [], name: 'getEventName', outputs: [{ name: '', type: 'string' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [], name: 'invalidResultIndex', outputs: [{ name: '', type: 'uint8' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: true, inputs: [], name: 'numOfResults', outputs: [{ name: '', type: 'uint8' }], payable: false, stateMutability: 'view', type: 'function' }, { constant: false, inputs: [], name: 'withdrawWinnings', outputs: [], payable: false, stateMutability: 'nonpayable', type: 'function' }, { constant: false, inputs: [{ name: '_newOwner', type: 'address' }], name: 'transferOwnership', outputs: [], payable: false, stateMutability: 'nonpayable', type: 'function' }, { constant: true, inputs: [], name: 'calculateBotContributorWinnings', outputs: [{ name: '', type: 'uint256' }], payable: false, stateMutability: 'view', type: 'function' }, { inputs: [{ name: '_owner', type: 'address' }, { name: '_centralizedOracle', type: 'address' }, { name: '_name', type: 'bytes32[10]' }, { name: '_resultNames', type: 'bytes32[10]' }, { name: '_bettingEndBlock', type: 'uint256' }, { name: '_resultSettingEndBlock', type: 'uint256' }, { name: '_addressManager', type: 'address' }], payable: false, stateMutability: 'nonpayable', type: 'constructor' }, { payable: true, stateMutability: 'payable', type: 'fallback' }, { anonymous: false, inputs: [{ indexed: true, name: '_eventAddress', type: 'address' }, { indexed: false, name: '_finalResultIndex', type: 'uint8' }], name: 'FinalResultSet', type: 'event' }, { anonymous: false, inputs: [{ indexed: true, name: '_winner', type: 'address' }, { indexed: false, name: '_MetrixTokenWon', type: 'uint256' }, { indexed: false, name: '_botTokenWon', type: 'uint256' }], name: 'WinningsWithdrawn', type: 'event' }, { anonymous: false, inputs: [{ indexed: true, name: '_previousOwner', type: 'address' }, { indexed: true, name: '_newOwner', type: 'address' }], name: 'OwnershipTransferred', type: 'event' }],
  },
};

Usage:

const ContractMetadata = require('./contract_metadata');

async function(args) {
  let {
    fromBlock, // number
    toBlock, // number
    addresses, // string array
    topics // string array
  } = args;

  if (addresses === undefined) {
    addresses = [];
  }
  if (topics === undefined) {
    topics = [];
  }

  // removeHexPrefix = true removes the '0x' hex prefix from all hex values
  return await mweb3.searchLogs(fromBlock, toBlock, addresses, topics, contractMetadata, true);
}

Contract.js

Instantiate a new instance of Contract:

const { Mweb3 } = require('mweb3');

const mweb3 = new Mweb3('http://metrix:metrix@localhost:13889');

// contractAddress = The address of your contract deployed on the blockchain
const contractAddress = 'f7b958eac2bdaca0f225b86d162f263441d23c19';

// contractAbi = The ABI of the contract
const contractAbi = [{"constant":false,"inputs":[{"name":"_eventAddress","type":"address"},{"name":"_eventName","type":"bytes32[10]"},{"name":"_eventResultNames","type":"bytes32[10]"},{"name":"_numOfResults","type":"uint8"},{"name":"_lastResultIndex","type":"uint8"},{"name":"_arbitrationEndBlock","type":"uint256"},{"name":"_consensusThreshold","type":"uint256"}],"name":"createDecentralizedOracle","outputs":[{"name":"","type":"address"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[{"name":"_eventAddress","type":"address"},{"name":"_eventName","type":"bytes32[10]"},{"name":"_eventResultNames","type":"bytes32[10]"},{"name":"_numOfResults","type":"uint8"},{"name":"_lastResultIndex","type":"uint8"},{"name":"_arbitrationEndBlock","type":"uint256"},{"name":"_consensusThreshold","type":"uint256"}],"name":"doesDecentralizedOracleExist","outputs":[{"name":"","type":"bool"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":false,"inputs":[{"name":"_oracle","type":"address"},{"name":"_eventAddress","type":"address"},{"name":"_eventName","type":"bytes32[10]"},{"name":"_eventResultNames","type":"bytes32[10]"},{"name":"_numOfResults","type":"uint8"},{"name":"_bettingEndBlock","type":"uint256"},{"name":"_resultSettingEndBlock","type":"uint256"},{"name":"_consensusThreshold","type":"uint256"}],"name":"createCentralizedOracle","outputs":[{"name":"","type":"address"}],"payable":false,"stateMutability":"nonpayable","type":"function"},{"constant":true,"inputs":[{"name":"_oracle","type":"address"},{"name":"_eventAddress","type":"address"},{"name":"_eventName","type":"bytes32[10]"},{"name":"_eventResultNames","type":"bytes32[10]"},{"name":"_numOfResults","type":"uint8"},{"name":"_bettingEndBlock","type":"uint256"},{"name":"_resultSettingEndBlock","type":"uint256"},{"name":"_consensusThreshold","type":"uint256"}],"name":"doesCentralizedOracleExist","outputs":[{"name":"","type":"bool"}],"payable":false,"stateMutability":"view","type":"function"},{"constant":true,"inputs":[{"name":"","type":"bytes32"}],"name":"oracles","outputs":[{"name":"","type":"address"}],"payable":false,"stateMutability":"view","type":"function"},{"inputs":[{"name":"_addressManager","type":"address"}],"payable":false,"stateMutability":"nonpayable","type":"constructor"},{"anonymous":false,"inputs":[{"indexed":true,"name":"_contractAddress","type":"address"},{"indexed":true,"name":"_oracle","type":"address"},{"indexed":true,"name":"_eventAddress","type":"address"},{"indexed":false,"name":"_name","type":"bytes32[10]"},{"indexed":false,"name":"_resultNames","type":"bytes32[10]"},{"indexed":false,"name":"_numOfResults","type":"uint8"},{"indexed":false,"name":"_bettingEndBlock","type":"uint256"},{"indexed":false,"name":"_resultSettingEndBlock","type":"uint256"},{"indexed":false,"name":"_consensusThreshold","type":"uint256"}],"name":"CentralizedOracleCreated","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"name":"_contractAddress","type":"address"},{"indexed":true,"name":"_eventAddress","type":"address"},{"indexed":false,"name":"_name","type":"bytes32[10]"},{"indexed":false,"name":"_resultNames","type":"bytes32[10]"},{"indexed":false,"name":"_numOfResults","type":"uint8"},{"indexed":false,"name":"_lastResultIndex","type":"uint8"},{"indexed":false,"name":"_arbitrationEndBlock","type":"uint256"},{"indexed":false,"name":"_consensusThreshold","type":"uint256"}],"name":"DecentralizedOracleCreated","type":"event"}];

// Create a Contract instance from the Mweb3 instance
const contract = mweb3.Contract(contractAddress, contractAbi);

call(methodName, params)

Executes a callcontract

// callcontract on a method named 'bettingEndBlock'
async function exampleCall(args) {
  const {
    senderAddress, // address
  } = args;

  return await contract.call('bettingEndBlock', {
    methodArgs: [],
    senderAddress: senderAddress,
  });
}

send(methodName, params)

Executes a sendtocontract

// sendtocontract on a method named 'setResult'
async function exampleSend(args) {
  const {
    resultIndex, // number
    senderAddress, // address
  } = args;

  return await contract.send('setResult', {
    methodArgs: [resultIndex],
    gasLimit: 1000000, // setting the gas limit to 1 million
    senderAddress: senderAddress,
  });
}

Encoder

Encoder static functions are exposed in Mweb3 instances.

const { Mweb3 } = require('mweb3');

const mweb3 = new Mweb3('http://metrix:metrix@localhost:13889');
mweb3.encoder.objToHash(abiObj, isFunction);
mweb3.encoder.addressToHex(address);
mweb3.encoder.boolToHex(value);
mweb3.encoder.intToHex(num);
mweb3.encoder.uintToHex(num);
mweb3.encoder.stringToHex(string, maxCharLen);
mweb3.encoder.stringArrayToHex(strArray, numOfItems);
mweb3.encoder.padHexString(hexStr);
mweb3.encoder.constructData(abi, methodName, args);

Decoder

Decoder static functions are exposed in Mweb3 instances.

const { Mweb3 } = require('mweb3');

const mweb3 = new Mweb3('http://metrix:metrix@localhost:13889');
mweb3.decoder.toMetrixAddress(hexAddress, isMainnet);
mweb3.decoder.removeHexPrefix(value);
mweb3.decoder.decodeSearchLog(rawOutput, contractMetadata, removeHexPrefix);
mweb3.decoder.decodeCall(rawOutput, contractABI, methodName, removeHexPrefix);

Utils

Utils static functions are exposed in Mweb3 instances.

const { Mweb3 } = require('mweb3');

const mweb3 = new Mweb3('http://metrix:metrix@localhost:13889');
mweb3.utils.paramsCheck(methodName, params, required, validators);
mweb3.utils.appendHexPrefix(value);
mweb3.utils.trimHexPrefix(str);
mweb3.utils.chunkString(str, length);
mweb3.utils.toUtf8(hex);
mweb3.utils.fromUtf8(str);
mweb3.utils.isJson(str);
mweb3.utils.isMetrixAddress(address);

Running Tests

You need to create a .env file in the root folder with the following variables in the following formats. Change it to how your environment is setup.

METRIX_RPC_ADDRESS='http://metrix:metrix@localhost:13889'
SENDER_ADDRESS='mMZK8FNPRm54jvTLAGEs1biTCgyCkcsmna'
WALLET_PASSPHRASE='metrix'