import { schemas, SchemaValidator } from '@0xproject/json-schemas'; import { TransactionReceiptWithDecodedLogs } from '@0xproject/types'; import { AbiDecoder, BigNumber, intervalUtils } from '@0xproject/utils'; import { Web3Wrapper } from '@0xproject/web3-wrapper'; import * as ethUtil from 'ethereumjs-util'; import * as _ from 'lodash'; import { artifacts } from './artifacts'; import { EtherTokenWrapper } from './contract_wrappers/ether_token_wrapper'; import { ExchangeWrapper } from './contract_wrappers/exchange_wrapper'; import { TokenRegistryWrapper } from './contract_wrappers/token_registry_wrapper'; import { TokenTransferProxyWrapper } from './contract_wrappers/token_transfer_proxy_wrapper'; import { TokenWrapper } from './contract_wrappers/token_wrapper'; import { OrderStateWatcher } from './order_watcher/order_state_watcher'; import { zeroExConfigSchema } from './schemas/zero_ex_config_schema'; import { ECSignature, Order, SignedOrder, Web3Provider, ZeroExConfig, ZeroExError } from './types'; import { assert } from './utils/assert'; import { constants } from './utils/constants'; import { decorators } from './utils/decorators'; import { signatureUtils } from './utils/signature_utils'; import { utils } from './utils/utils'; /** * The ZeroEx class is the single entry-point into the 0x.js library. It contains all of the library's functionality * and all calls to the library should be made through a ZeroEx instance. */ export class ZeroEx { /** * When creating an order without a specified taker or feeRecipient you must supply the Solidity * address null type (as opposed to Javascripts `null`, `undefined` or empty string). We expose * this constant for your convenience. */ public static NULL_ADDRESS = constants.NULL_ADDRESS; /** * An instance of the ExchangeWrapper class containing methods for interacting with the 0x Exchange smart contract. */ public exchange: ExchangeWrapper; /** * An instance of the TokenRegistryWrapper class containing methods for interacting with the 0x * TokenRegistry smart contract. */ public tokenRegistry: TokenRegistryWrapper; /** * An instance of the TokenWrapper class containing methods for interacting with any ERC20 token smart contract. */ public token: TokenWrapper; /** * An instance of the EtherTokenWrapper class containing methods for interacting with the * wrapped ETH ERC20 token smart contract. */ public etherToken: EtherTokenWrapper; /** * An instance of the TokenTransferProxyWrapper class containing methods for interacting with the * tokenTransferProxy smart contract. */ public proxy: TokenTransferProxyWrapper; /** * An instance of the OrderStateWatcher class containing methods for watching a set of orders for relevant * blockchain state changes. */ public orderStateWatcher: OrderStateWatcher; private _web3Wrapper: Web3Wrapper; private _abiDecoder: AbiDecoder; /** * Verifies that the elliptic curve signature `signature` was generated * by signing `data` with the private key corresponding to the `signerAddress` address. * @param data The hex encoded data signed by the supplied signature. * @param signature An object containing the elliptic curve signature parameters. * @param signerAddress The hex encoded address that signed the data, producing the supplied signature. * @return Whether the signature is valid for the supplied signerAddress and data. */ public static isValidSignature(data: string, signature: ECSignature, signerAddress: string): boolean { const normalizedSignerAddress = signerAddress.toLowerCase(); assert.isHexString('data', data); assert.doesConformToSchema('signature', signature, schemas.ecSignatureSchema); assert.isETHAddressHex('signerAddress', normalizedSignerAddress); const isValidSignature = signatureUtils.isValidSignature(data, signature, normalizedSignerAddress); return isValidSignature; } /** * Generates a pseudo-random 256-bit salt. * The salt can be included in an 0x order, ensuring that the order generates a unique orderHash * and will not collide with other outstanding orders that are identical in all other parameters. * @return A pseudo-random 256-bit number that can be used as a salt. */ public static generatePseudoRandomSalt(): BigNumber { // BigNumber.random returns a pseudo-random number between 0 & 1 with a passed in number of decimal places. // Source: https://mikemcl.github.io/bignumber.js/#random const randomNumber = BigNumber.random(constants.MAX_DIGITS_IN_UNSIGNED_256_INT); const factor = new BigNumber(10).pow(constants.MAX_DIGITS_IN_UNSIGNED_256_INT - 1); const salt = randomNumber.times(factor).round(); return salt; } /** * Checks if the supplied hex encoded order hash is valid. * Note: Valid means it has the expected format, not that an order with the orderHash exists. * Use this method when processing orderHashes submitted as user input. * @param orderHash Hex encoded orderHash. * @return Whether the supplied orderHash has the expected format. */ public static isValidOrderHash(orderHash: string): boolean { // Since this method can be called to check if any arbitrary string conforms to an orderHash's // format, we only assert that we were indeed passed a string. assert.isString('orderHash', orderHash); const schemaValidator = new SchemaValidator(); const isValidOrderHash = schemaValidator.validate(orderHash, schemas.orderHashSchema).valid; return isValidOrderHash; } /** * A unit amount is defined as the amount of a token above the specified decimal places (integer part). * E.g: If a currency has 18 decimal places, 1e18 or one quintillion of the currency is equivalent * to 1 unit. * @param amount The amount in baseUnits that you would like converted to units. * @param decimals The number of decimal places the unit amount has. * @return The amount in units. */ public static toUnitAmount(amount: BigNumber, decimals: number): BigNumber { assert.isValidBaseUnitAmount('amount', amount); assert.isNumber('decimals', decimals); const aUnit = new BigNumber(10).pow(decimals); const unit = amount.div(aUnit); return unit; } /** * A baseUnit is defined as the smallest denomination of a token. An amount expressed in baseUnits * is the amount expressed in the smallest denomination. * E.g: 1 unit of a token with 18 decimal places is expressed in baseUnits as 1000000000000000000 * @param amount The amount of units that you would like converted to baseUnits. * @param decimals The number of decimal places the unit amount has. * @return The amount in baseUnits. */ public static toBaseUnitAmount(amount: BigNumber, decimals: number): BigNumber { assert.isBigNumber('amount', amount); assert.isNumber('decimals', decimals); const unit = new BigNumber(10).pow(decimals); const baseUnitAmount = amount.times(unit); const hasDecimals = baseUnitAmount.decimalPlaces() !== 0; if (hasDecimals) { throw new Error(`Invalid unit amount: ${amount.toString()} - Too many decimal places`); } return baseUnitAmount; } /** * Computes the orderHash for a supplied order. * @param order An object that conforms to the Order or SignedOrder interface definitions. * @return The resulting orderHash from hashing the supplied order. */ @decorators.syncZeroExErrorHandler public static getOrderHashHex(order: Order | SignedOrder): string { assert.doesConformToSchema('order', order, schemas.orderSchema); const orderHashHex = utils.getOrderHashHex(order); return orderHashHex; } /** * Instantiates a new ZeroEx instance that provides the public interface to the 0x.js library. * @param provider The Web3.js Provider instance you would like the 0x.js library to use for interacting with * the Ethereum network. * @param config The configuration object. Look up the type for the description. * @return An instance of the 0x.js ZeroEx class. */ constructor(provider: Web3Provider, config: ZeroExConfig) { assert.isWeb3Provider('provider', provider); assert.doesConformToSchema('config', config, zeroExConfigSchema); const artifactJSONs = _.values(artifacts); const abiArrays = _.map(artifactJSONs, artifact => artifact.abi); this._abiDecoder = new AbiDecoder(abiArrays); const defaults = { gasPrice: config.gasPrice, }; this._web3Wrapper = new Web3Wrapper(provider, defaults); this.proxy = new TokenTransferProxyWrapper( this._web3Wrapper, config.networkId, config.tokenTransferProxyContractAddress, ); this.token = new TokenWrapper(this._web3Wrapper, config.networkId, this._abiDecoder, this.proxy); this.exchange = new ExchangeWrapper( this._web3Wrapper, config.networkId, this._abiDecoder, this.token, config.exchangeContractAddress, config.zrxContractAddress, ); this.tokenRegistry = new TokenRegistryWrapper( this._web3Wrapper, config.networkId, config.tokenRegistryContractAddress, ); this.etherToken = new EtherTokenWrapper(this._web3Wrapper, config.networkId, this._abiDecoder, this.token); this.orderStateWatcher = new OrderStateWatcher( this._web3Wrapper, this._abiDecoder, this.token, this.exchange, config.orderWatcherConfig, ); } /** * Sets a new web3 provider for 0x.js. Updating the provider will stop all * subscriptions so you will need to re-subscribe to all events relevant to your app after this call. * @param provider The Web3Provider you would like the 0x.js library to use from now on. * @param networkId The id of the network your provider is connected to */ public setProvider(provider: Web3Provider, networkId: number): void { this._web3Wrapper.setProvider(provider); (this.exchange as any)._invalidateContractInstances(); (this.exchange as any)._setNetworkId(networkId); (this.tokenRegistry as any)._invalidateContractInstance(); (this.tokenRegistry as any)._setNetworkId(networkId); (this.token as any)._invalidateContractInstances(); (this.token as any)._setNetworkId(networkId); (this.proxy as any)._invalidateContractInstance(); (this.proxy as any)._setNetworkId(networkId); (this.etherToken as any)._invalidateContractInstance(); (this.etherToken as any)._setNetworkId(networkId); } /** * Get user Ethereum addresses available through the supplied web3 provider available for sending transactions. * @return An array of available user Ethereum addresses. */ public async getAvailableAddressesAsync(): Promise { const availableAddresses = await this._web3Wrapper.getAvailableAddressesAsync(); return availableAddresses; } /** * Signs an orderHash and returns it's elliptic curve signature. * This method currently supports TestRPC, Geth and Parity above and below V1.6.6 * @param orderHash Hex encoded orderHash to sign. * @param signerAddress The hex encoded Ethereum address you wish to sign it with. This address * must be available via the Web3.Provider supplied to 0x.js. * @param shouldAddPersonalMessagePrefix Some signers add the personal message prefix `\x19Ethereum Signed Message` * themselves (e.g Parity Signer, Ledger, TestRPC) and others expect it to already be done by the client * (e.g Metamask). Depending on which signer this request is going to, decide on whether to add the prefix * before sending the request. * @return An object containing the Elliptic curve signature parameters generated by signing the orderHash. */ public async signOrderHashAsync( orderHash: string, signerAddress: string, shouldAddPersonalMessagePrefix: boolean, ): Promise { assert.isHexString('orderHash', orderHash); const normalizedSignerAddress = signerAddress.toLowerCase(); assert.isETHAddressHex('signerAddress', normalizedSignerAddress); await assert.isSenderAddressAsync('signerAddress', normalizedSignerAddress, this._web3Wrapper); let msgHashHex = orderHash; if (shouldAddPersonalMessagePrefix) { const orderHashBuff = ethUtil.toBuffer(orderHash); const msgHashBuff = ethUtil.hashPersonalMessage(orderHashBuff); msgHashHex = ethUtil.bufferToHex(msgHashBuff); } const signature = await this._web3Wrapper.signTransactionAsync(normalizedSignerAddress, msgHashHex); // HACK: There is no consensus on whether the signatureHex string should be formatted as // v + r + s OR r + s + v, and different clients (even different versions of the same client) // return the signature params in different orders. In order to support all client implementations, // we parse the signature in both ways, and evaluate if either one is a valid signature. const validVParamValues = [27, 28]; const ecSignatureVRS = signatureUtils.parseSignatureHexAsVRS(signature); if (_.includes(validVParamValues, ecSignatureVRS.v)) { const isValidVRSSignature = ZeroEx.isValidSignature(orderHash, ecSignatureVRS, normalizedSignerAddress); if (isValidVRSSignature) { return ecSignatureVRS; } } const ecSignatureRSV = signatureUtils.parseSignatureHexAsRSV(signature); if (_.includes(validVParamValues, ecSignatureRSV.v)) { const isValidRSVSignature = ZeroEx.isValidSignature(orderHash, ecSignatureRSV, normalizedSignerAddress); if (isValidRSVSignature) { return ecSignatureRSV; } } throw new Error(ZeroExError.InvalidSignature); } /** * Waits for a transaction to be mined and returns the transaction receipt. * @param txHash Transaction hash * @param pollingIntervalMs How often (in ms) should we check if the transaction is mined. * @param timeoutMs How long (in ms) to poll for transaction mined until aborting. * @return Transaction receipt with decoded log args. */ public async awaitTransactionMinedAsync( txHash: string, pollingIntervalMs = 1000, timeoutMs?: number, ): Promise { let timeoutExceeded = false; if (timeoutMs) { setTimeout(() => (timeoutExceeded = true), timeoutMs); } const txReceiptPromise = new Promise( (resolve: (receipt: TransactionReceiptWithDecodedLogs) => void, reject) => { const intervalId = intervalUtils.setAsyncExcludingInterval( async () => { if (timeoutExceeded) { intervalUtils.clearAsyncExcludingInterval(intervalId); return reject(ZeroExError.TransactionMiningTimeout); } const transactionReceipt = await this._web3Wrapper.getTransactionReceiptAsync(txHash); if (!_.isNull(transactionReceipt)) { intervalUtils.clearAsyncExcludingInterval(intervalId); const logsWithDecodedArgs = _.map( transactionReceipt.logs, this._abiDecoder.tryToDecodeLogOrNoop.bind(this._abiDecoder), ); const transactionReceiptWithDecodedLogArgs: TransactionReceiptWithDecodedLogs = { ...transactionReceipt, logs: logsWithDecodedArgs, }; resolve(transactionReceiptWithDecodedLogArgs); } }, pollingIntervalMs, (err: Error) => { intervalUtils.clearAsyncExcludingInterval(intervalId); reject(err); }, ); }, ); const txReceipt = await txReceiptPromise; return txReceipt; } /* * HACK: `TokenWrapper` needs a token transfer proxy address. `TokenTransferProxy` address is fetched from * an `ExchangeWrapper`. `ExchangeWrapper` needs `TokenWrapper` to validate orders, creating a dependency cycle. * In order to break this - we create this function here and pass it as a parameter to the `TokenWrapper` * and `ProxyWrapper`. */ private async _getTokenTransferProxyAddressAsync(): Promise { const tokenTransferProxyAddress = await (this.exchange as any)._getTokenTransferProxyAddressAsync(); return tokenTransferProxyAddress; } }