import { schemas, SchemaValidator } from '@0xproject/json-schemas';
import { 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,
TransactionReceiptWithDecodedLogs,
Web3Provider,
ZeroExConfig,
ZeroExError,
} from './types';
import { AbiDecoder } from './utils/abi_decoder';
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 {
assert.isHexString('data', data);
assert.doesConformToSchema('signature', signature, schemas.ecSignatureSchema);
assert.isETHAddressHex('signerAddress', signerAddress);
const isValidSignature = signatureUtils.isValidSignature(data, signature, signerAddress);
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<string[]> {
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<ECSignature> {
assert.isHexString('orderHash', orderHash);
await assert.isSenderAddressAsync('signerAddress', signerAddress, 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(signerAddress, 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, signerAddress);
if (isValidVRSSignature) {
return ecSignatureVRS;
}
}
const ecSignatureRSV = signatureUtils.parseSignatureHexAsRSV(signature);
if (_.includes(validVParamValues, ecSignatureRSV.v)) {
const isValidRSVSignature = ZeroEx.isValidSignature(orderHash, ecSignatureRSV, signerAddress);
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<TransactionReceiptWithDecodedLogs> {
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);
},
);
},
);
return txReceiptPromise;
}
/*
* 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<string> {
const tokenTransferProxyAddress = await (this.exchange as any)._getTokenTransferProxyAddressAsync();
return tokenTransferProxyAddress;
}
}
