import { TransactionReceipt, TxData } from '@0xproject/types'; import { BigNumber, promisify } from '@0xproject/utils'; import * as _ from 'lodash'; import * as Web3 from 'web3'; interface RawLogEntry { logIndex: string | null; transactionIndex: string | null; transactionHash: string; blockHash: string | null; blockNumber: string | null; address: string; data: string; topics: string[]; } export class Web3Wrapper { private _web3: Web3; private _defaults: Partial; private _jsonRpcRequestId: number; constructor(provider: Web3.Provider, defaults?: Partial) { if (_.isUndefined((provider as any).sendAsync)) { // Web3@1.0 provider doesn't support synchronous http requests, // so it only has an async `send` method, instead of a `send` and `sendAsync` in web3@0.x.x` // We re-assign the send method so that Web3@1.0 providers work with 0x.js (provider as any).sendAsync = (provider as any).send; } this._web3 = new Web3(); this._web3.setProvider(provider); this._defaults = defaults || {}; this._jsonRpcRequestId = 0; } public getContractDefaults(): Partial { return this._defaults; } public setProvider(provider: Web3.Provider) { this._web3.setProvider(provider); } public isAddress(address: string): boolean { return this._web3.isAddress(address); } public async isSenderAddressAvailableAsync(senderAddress: string): Promise { const addresses = await this.getAvailableAddressesAsync(); return _.includes(addresses, senderAddress); } public async getNodeVersionAsync(): Promise { const nodeVersion = await promisify(this._web3.version.getNode)(); return nodeVersion; } public async getNetworkIdAsync(): Promise { const networkIdStr = await promisify(this._web3.version.getNetwork)(); const networkId = _.parseInt(networkIdStr); return networkId; } public async getTransactionReceiptAsync(txHash: string): Promise { const transactionReceipt = await promisify(this._web3.eth.getTransactionReceipt)(txHash); if (!_.isNull(transactionReceipt)) { transactionReceipt.status = this._normalizeTxReceiptStatus(transactionReceipt.status); } return transactionReceipt; } public getCurrentProvider(): Web3.Provider { return this._web3.currentProvider; } public toWei(ethAmount: BigNumber): BigNumber { const balanceWei = this._web3.toWei(ethAmount, 'ether'); return balanceWei; } public async getBalanceInWeiAsync(owner: string): Promise { let balanceInWei = await promisify(this._web3.eth.getBalance)(owner); // Rewrap in a new BigNumber balanceInWei = new BigNumber(balanceInWei); return balanceInWei; } public async doesContractExistAtAddressAsync(address: string): Promise { const code = await promisify(this._web3.eth.getCode)(address); // Regex matches 0x0, 0x00, 0x in order to accommodate poorly implemented clients const codeIsEmpty = /^0x0{0,40}$/i.test(code); return !codeIsEmpty; } public async signTransactionAsync(address: string, message: string): Promise { const signData = await promisify(this._web3.eth.sign)(address, message); return signData; } public async getBlockNumberAsync(): Promise { const blockNumber = await promisify(this._web3.eth.getBlockNumber)(); return blockNumber; } public async getBlockAsync(blockParam: string | Web3.BlockParam): Promise { const block = await promisify(this._web3.eth.getBlock)(blockParam); return block; } public async getBlockTimestampAsync(blockParam: string | Web3.BlockParam): Promise { const { timestamp } = await this.getBlockAsync(blockParam); return timestamp; } public async getAvailableAddressesAsync(): Promise { const addresses = await promisify(this._web3.eth.getAccounts)(); return addresses; } public async getLogsAsync(filter: Web3.FilterObject): Promise { let fromBlock = filter.fromBlock; if (_.isNumber(fromBlock)) { fromBlock = this._web3.toHex(fromBlock); } let toBlock = filter.toBlock; if (_.isNumber(toBlock)) { toBlock = this._web3.toHex(toBlock); } const serializedFilter = { ...filter, fromBlock, toBlock, }; const payload = { jsonrpc: '2.0', id: this._jsonRpcRequestId++, method: 'eth_getLogs', params: [serializedFilter], }; const rawLogs = await this._sendRawPayloadAsync(payload); const formattedLogs = _.map(rawLogs, this._formatLog.bind(this)); return formattedLogs; } public getContractFromAbi(abi: Web3.ContractAbi): Web3.Contract { const web3Contract = this._web3.eth.contract(abi); return web3Contract; } public getContractInstance(abi: Web3.ContractAbi, address: string): Web3.ContractInstance { const web3ContractInstance = this.getContractFromAbi(abi).at(address); return web3ContractInstance; } public async estimateGasAsync(data: string): Promise { const gas = await promisify(this._web3.eth.estimateGas)({ data }); return gas; } public async sendTransactionAsync(txData: Web3.TxData): Promise { const txHash = await promisify(this._web3.eth.sendTransaction)(txData); return txHash; } private async _sendRawPayloadAsync(payload: Web3.JSONRPCRequestPayload): Promise { const sendAsync = this._web3.currentProvider.sendAsync.bind(this._web3.currentProvider); const response = await promisify(sendAsync)(payload); const result = response.result; return result; } private _normalizeTxReceiptStatus(status: undefined | null | string | 0 | 1): null | 0 | 1 { // Transaction status might have four values // undefined - Testrpc and other old clients // null - New clients on old transactions // number - Parity // hex - Geth if (_.isString(status)) { return this._web3.toDecimal(status) as 0 | 1; } else if (_.isUndefined(status)) { return null; } else { return status; } } private _formatLog(rawLog: RawLogEntry): Web3.LogEntry { const formattedLog = { ...rawLog, logIndex: this._hexToDecimal(rawLog.logIndex), blockNumber: this._hexToDecimal(rawLog.blockNumber), transactionIndex: this._hexToDecimal(rawLog.transactionIndex), }; return formattedLog; } private _hexToDecimal(hex: string | null): number | null { if (_.isNull(hex)) { return null; } const decimal = this._web3.toDecimal(hex); return decimal; } }