import { ERC20TokenContract, ERC20TokenEventArgs, ERC20TokenEvents } from '@0xproject/abi-gen-wrappers';
import { ERC20Token } from '@0xproject/contract-artifacts';
import { schemas } from '@0xproject/json-schemas';
import { BigNumber } from '@0xproject/utils';
import { Web3Wrapper } from '@0xproject/web3-wrapper';
import { ContractAbi, LogWithDecodedArgs } from 'ethereum-types';
import * as _ from 'lodash';
import { methodOptsSchema } from '../schemas/method_opts_schema';
import { txOptsSchema } from '../schemas/tx_opts_schema';
import {
BlockRange,
ContractWrappersError,
EventCallback,
IndexedFilterValues,
MethodOpts,
TransactionOpts,
} from '../types';
import { assert } from '../utils/assert';
import { constants } from '../utils/constants';
import { ContractWrapper } from './contract_wrapper';
import { ERC20ProxyWrapper } from './erc20_proxy_wrapper';
const removeUndefinedProperties = _.pickBy;
/**
* This class includes all the functionality related to interacting with ERC20 token contracts.
* All ERC20 method calls are supported, along with some convenience methods for getting/setting allowances
* to the 0x ERC20 Proxy smart contract.
*/
export class ERC20TokenWrapper extends ContractWrapper {
public abi: ContractAbi = ERC20Token.compilerOutput.abi;
public UNLIMITED_ALLOWANCE_IN_BASE_UNITS = constants.UNLIMITED_ALLOWANCE_IN_BASE_UNITS;
private _tokenContractsByAddress: { [address: string]: ERC20TokenContract };
private _erc20ProxyWrapper: ERC20ProxyWrapper;
/**
* Instantiate ERC20TokenWrapper
* @param web3Wrapper Web3Wrapper instance to use
* @param erc20ProxyWrapper The ERC20ProxyWrapper instance to use
* @param blockPollingIntervalMs The block polling interval to use for active subscriptions
*/
constructor(web3Wrapper: Web3Wrapper, erc20ProxyWrapper: ERC20ProxyWrapper, blockPollingIntervalMs?: number) {
super(web3Wrapper, blockPollingIntervalMs);
this._tokenContractsByAddress = {};
this._erc20ProxyWrapper = erc20ProxyWrapper;
}
/**
* Retrieves an owner's ERC20 token balance.
* @param tokenAddress The hex encoded contract Ethereum address where the ERC20 token is deployed.
* @param ownerAddress The hex encoded user Ethereum address whose balance you would like to check.
* @param methodOpts Optional arguments this method accepts.
* @return The owner's ERC20 token balance in base units.
*/
public async getBalanceAsync(
tokenAddress: string,
ownerAddress: string,
methodOpts: MethodOpts = {},
): Promise<BigNumber> {
assert.isETHAddressHex('ownerAddress', ownerAddress);
assert.isETHAddressHex('tokenAddress', tokenAddress);
assert.doesConformToSchema('methodOpts', methodOpts, methodOptsSchema);
const normalizedTokenAddress = tokenAddress.toLowerCase();
const normalizedOwnerAddress = ownerAddress.toLowerCase();
const tokenContract = await this._getTokenContractAsync(normalizedTokenAddress);
const txData = {};
let balance = await tokenContract.balanceOf.callAsync(normalizedOwnerAddress, txData, methodOpts.defaultBlock);
// Wrap BigNumbers returned from web3 with our own (later) version of BigNumber
balance = new BigNumber(balance);
return balance;
}
/**
* Sets the spender's allowance to a specified number of baseUnits on behalf of the owner address.
* Equivalent to the ERC20 spec method `approve`.
* @param tokenAddress The hex encoded contract Ethereum address where the ERC20 token is deployed.
* @param ownerAddress The hex encoded user Ethereum address who would like to set an allowance
* for spenderAddress.
* @param spenderAddress The hex encoded user Ethereum address who will be able to spend the set allowance.
* @param amountInBaseUnits The allowance amount you would like to set.
* @param txOpts Transaction parameters.
* @return Transaction hash.
*/
public async setAllowanceAsync(
tokenAddress: string,
ownerAddress: string,
spenderAddress: string,
amountInBaseUnits: BigNumber,
txOpts: TransactionOpts = {},
): Promise<string> {
assert.isETHAddressHex('tokenAddress', tokenAddress);
await assert.isSenderAddressAsync('ownerAddress', ownerAddress, this._web3Wrapper);
assert.isETHAddressHex('spenderAddress', spenderAddress);
assert.isValidBaseUnitAmount('amountInBaseUnits', amountInBaseUnits);
assert.doesConformToSchema('txOpts', txOpts, txOptsSchema);
const normalizedTokenAddress = tokenAddress.toLowerCase();
const normalizedOwnerAddress = ownerAddress.toLowerCase();
const normalizedSpenderAddress = spenderAddress.toLowerCase();
const tokenContract = await this._getTokenContractAsync(normalizedTokenAddress);
const txHash = await tokenContract.approve.sendTransactionAsync(
normalizedSpenderAddress,
amountInBaseUnits,
removeUndefinedProperties({
from: normalizedOwnerAddress,
gas: txOpts.gasLimit,
gasPrice: txOpts.gasPrice,
}),
);
return txHash;
}
/**
* Sets the spender's allowance to an unlimited number of baseUnits on behalf of the owner address.
* Equivalent to the ERC20 spec method `approve`.
* Setting an unlimited allowance will lower the gas cost for filling orders involving tokens that forego updating
* allowances set to the max amount (e.g ZRX, WETH)
* @param tokenAddress The hex encoded contract Ethereum address where the ERC20 token is deployed.
* @param ownerAddress The hex encoded user Ethereum address who would like to set an allowance
* for spenderAddress.
* @param spenderAddress The hex encoded user Ethereum address who will be able to spend the set allowance.
* @param txOpts Transaction parameters.
* @return Transaction hash.
*/
public async setUnlimitedAllowanceAsync(
tokenAddress: string,
ownerAddress: string,
spenderAddress: string,
txOpts: TransactionOpts = {},
): Promise<string> {
const txHash = await this.setAllowanceAsync(
tokenAddress,
ownerAddress,
spenderAddress,
this.UNLIMITED_ALLOWANCE_IN_BASE_UNITS,
txOpts,
);
return txHash;
}
/**
* Retrieves the owners allowance in baseUnits set to the spender's address.
* @param tokenAddress The hex encoded contract Ethereum address where the ERC20 token is deployed.
* @param ownerAddress The hex encoded user Ethereum address whose allowance to spenderAddress
* you would like to retrieve.
* @param spenderAddress The hex encoded user Ethereum address who can spend the allowance you are fetching.
* @param methodOpts Optional arguments this method accepts.
*/
public async getAllowanceAsync(
tokenAddress: string,
ownerAddress: string,
spenderAddress: string,
methodOpts: MethodOpts = {},
): Promise<BigNumber> {
assert.isETHAddressHex('tokenAddress', tokenAddress);
assert.isETHAddressHex('ownerAddress', ownerAddress);
assert.isETHAddressHex('spenderAddress', spenderAddress);
assert.doesConformToSchema('methodOpts', methodOpts, methodOptsSchema);
const normalizedTokenAddress = tokenAddress.toLowerCase();
const normalizedOwnerAddress = ownerAddress.toLowerCase();
const normalizedSpenderAddress = spenderAddress.toLowerCase();
const tokenContract = await this._getTokenContractAsync(normalizedTokenAddress);
const txData = {};
let allowanceInBaseUnits = await tokenContract.allowance.callAsync(
normalizedOwnerAddress,
normalizedSpenderAddress,
txData,
methodOpts.defaultBlock,
);
// Wrap BigNumbers returned from web3 with our own (later) version of BigNumber
allowanceInBaseUnits = new BigNumber(allowanceInBaseUnits);
return allowanceInBaseUnits;
}
/**
* Retrieves the owner's allowance in baseUnits set to the 0x proxy contract.
* @param tokenAddress The hex encoded contract Ethereum address where the ERC20 token is deployed.
* @param ownerAddress The hex encoded user Ethereum address whose proxy contract allowance we are retrieving.
* @param methodOpts Optional arguments this method accepts.
*/
public async getProxyAllowanceAsync(
tokenAddress: string,
ownerAddress: string,
methodOpts: MethodOpts = {},
): Promise<BigNumber> {
const proxyAddress = this._erc20ProxyWrapper.address;
const allowanceInBaseUnits = await this.getAllowanceAsync(tokenAddress, ownerAddress, proxyAddress, methodOpts);
return allowanceInBaseUnits;
}
/**
* Sets the 0x proxy contract's allowance to a specified number of a tokens' baseUnits on behalf
* of an owner address.
* @param tokenAddress The hex encoded contract Ethereum address where the ERC20 token is deployed.
* @param ownerAddress The hex encoded user Ethereum address who is setting an allowance
* for the Proxy contract.
* @param amountInBaseUnits The allowance amount specified in baseUnits.
* @param txOpts Transaction parameters.
* @return Transaction hash.
*/
public async setProxyAllowanceAsync(
tokenAddress: string,
ownerAddress: string,
amountInBaseUnits: BigNumber,
txOpts: TransactionOpts = {},
): Promise<string> {
const proxyAddress = this._erc20ProxyWrapper.address;
const txHash = await this.setAllowanceAsync(
tokenAddress,
ownerAddress,
proxyAddress,
amountInBaseUnits,
txOpts,
);
return txHash;
}
/**
* Sets the 0x proxy contract's allowance to a unlimited number of a tokens' baseUnits on behalf
* of an owner address.
* Setting an unlimited allowance will lower the gas cost for filling orders involving tokens that forego updating
* allowances set to the max amount (e.g ZRX, WETH)
* @param tokenAddress The hex encoded contract Ethereum address where the ERC20 token is deployed.
* @param ownerAddress The hex encoded user Ethereum address who is setting an allowance
* for the Proxy contract.
* @param txOpts Transaction parameters.
* @return Transaction hash.
*/
public async setUnlimitedProxyAllowanceAsync(
tokenAddress: string,
ownerAddress: string,
txOpts: TransactionOpts = {},
): Promise<string> {
const txHash = await this.setProxyAllowanceAsync(
tokenAddress,
ownerAddress,
this.UNLIMITED_ALLOWANCE_IN_BASE_UNITS,
txOpts,
);
return txHash;
}
/**
* Transfers `amountInBaseUnits` ERC20 tokens from `fromAddress` to `toAddress`.
* @param tokenAddress The hex encoded contract Ethereum address where the ERC20 token is deployed.
* @param fromAddress The hex encoded user Ethereum address that will send the funds.
* @param toAddress The hex encoded user Ethereum address that will receive the funds.
* @param amountInBaseUnits The amount (specified in baseUnits) of the token to transfer.
* @param txOpts Transaction parameters.
* @return Transaction hash.
*/
public async transferAsync(
tokenAddress: string,
fromAddress: string,
toAddress: string,
amountInBaseUnits: BigNumber,
txOpts: TransactionOpts = {},
): Promise<string> {
assert.isETHAddressHex('tokenAddress', tokenAddress);
await assert.isSenderAddressAsync('fromAddress', fromAddress, this._web3Wrapper);
assert.isETHAddressHex('toAddress', toAddress);
assert.isValidBaseUnitAmount('amountInBaseUnits', amountInBaseUnits);
assert.doesConformToSchema('txOpts', txOpts, txOptsSchema);
const normalizedTokenAddress = tokenAddress.toLowerCase();
const normalizedFromAddress = fromAddress.toLowerCase();
const normalizedToAddress = toAddress.toLowerCase();
const tokenContract = await this._getTokenContractAsync(normalizedTokenAddress);
const fromAddressBalance = await this.getBalanceAsync(normalizedTokenAddress, normalizedFromAddress);
if (fromAddressBalance.lessThan(amountInBaseUnits)) {
throw new Error(ContractWrappersError.InsufficientBalanceForTransfer);
}
const txHash = await tokenContract.transfer.sendTransactionAsync(
normalizedToAddress,
amountInBaseUnits,
removeUndefinedProperties({
from: normalizedFromAddress,
gas: txOpts.gasLimit,
gasPrice: txOpts.gasPrice,
}),
);
return txHash;
}
/**
* Transfers `amountInBaseUnits` ERC20 tokens from `fromAddress` to `toAddress`.
* Requires the fromAddress to have sufficient funds and to have approved an allowance of
* `amountInBaseUnits` to `senderAddress`.
* @param tokenAddress The hex encoded contract Ethereum address where the ERC20 token is deployed.
* @param fromAddress The hex encoded user Ethereum address whose funds are being sent.
* @param toAddress The hex encoded user Ethereum address that will receive the funds.
* @param senderAddress The hex encoded user Ethereum address whose initiates the fund transfer. The
* `fromAddress` must have set an allowance to the `senderAddress`
* before this call.
* @param amountInBaseUnits The amount (specified in baseUnits) of the token to transfer.
* @param txOpts Transaction parameters.
* @return Transaction hash.
*/
public async transferFromAsync(
tokenAddress: string,
fromAddress: string,
toAddress: string,
senderAddress: string,
amountInBaseUnits: BigNumber,
txOpts: TransactionOpts = {},
): Promise<string> {
assert.isETHAddressHex('tokenAddress', tokenAddress);
assert.isETHAddressHex('fromAddress', fromAddress);
assert.isETHAddressHex('toAddress', toAddress);
await assert.isSenderAddressAsync('senderAddress', senderAddress, this._web3Wrapper);
assert.isValidBaseUnitAmount('amountInBaseUnits', amountInBaseUnits);
assert.doesConformToSchema('txOpts', txOpts, txOptsSchema);
const normalizedToAddress = toAddress.toLowerCase();
const normalizedFromAddress = fromAddress.toLowerCase();
const normalizedTokenAddress = tokenAddress.toLowerCase();
const normalizedSenderAddress = senderAddress.toLowerCase();
const tokenContract = await this._getTokenContractAsync(normalizedTokenAddress);
const fromAddressAllowance = await this.getAllowanceAsync(
normalizedTokenAddress,
normalizedFromAddress,
normalizedSenderAddress,
);
if (fromAddressAllowance.lessThan(amountInBaseUnits)) {
throw new Error(ContractWrappersError.InsufficientAllowanceForTransfer);
}
const fromAddressBalance = await this.getBalanceAsync(normalizedTokenAddress, normalizedFromAddress);
if (fromAddressBalance.lessThan(amountInBaseUnits)) {
throw new Error(ContractWrappersError.InsufficientBalanceForTransfer);
}
const txHash = await tokenContract.transferFrom.sendTransactionAsync(
normalizedFromAddress,
normalizedToAddress,
amountInBaseUnits,
removeUndefinedProperties({
from: normalizedSenderAddress,
gas: txOpts.gasLimit,
gasPrice: txOpts.gasPrice,
}),
);
return txHash;
}
/**
* Subscribe to an event type emitted by the Token contract.
* @param tokenAddress The hex encoded address where the ERC20 token is deployed.
* @param eventName The token contract event you would like to subscribe to.
* @param indexFilterValues An object where the keys are indexed args returned by the event and
* the value is the value you are interested in. E.g `{maker: aUserAddressHex}`
* @param callback Callback that gets called when a log is added/removed
* @param isVerbose Enable verbose subscription warnings (e.g recoverable network issues encountered)
* @return Subscription token used later to unsubscribe
*/
public subscribe<ArgsType extends ERC20TokenEventArgs>(
tokenAddress: string,
eventName: ERC20TokenEvents,
indexFilterValues: IndexedFilterValues,
callback: EventCallback<ArgsType>,
isVerbose: boolean = false,
): string {
assert.isETHAddressHex('tokenAddress', tokenAddress);
assert.doesBelongToStringEnum('eventName', eventName, ERC20TokenEvents);
assert.doesConformToSchema('indexFilterValues', indexFilterValues, schemas.indexFilterValuesSchema);
assert.isFunction('callback', callback);
const normalizedTokenAddress = tokenAddress.toLowerCase();
const subscriptionToken = this._subscribe<ArgsType>(
normalizedTokenAddress,
eventName,
indexFilterValues,
ERC20Token.compilerOutput.abi,
callback,
isVerbose,
);
return subscriptionToken;
}
/**
* Cancel a subscription
* @param subscriptionToken Subscription token returned by `subscribe()`
*/
public unsubscribe(subscriptionToken: string): void {
assert.isValidSubscriptionToken('subscriptionToken', subscriptionToken);
this._unsubscribe(subscriptionToken);
}
/**
* Cancels all existing subscriptions
*/
public unsubscribeAll(): void {
super._unsubscribeAll();
}
/**
* Gets historical logs without creating a subscription
* @param tokenAddress An address of the token that emitted the logs.
* @param eventName The token contract event you would like to subscribe to.
* @param blockRange Block range to get logs from.
* @param indexFilterValues An object where the keys are indexed args returned by the event and
* the value is the value you are interested in. E.g `{_from: aUserAddressHex}`
* @return Array of logs that match the parameters
*/
public async getLogsAsync<ArgsType extends ERC20TokenEventArgs>(
tokenAddress: string,
eventName: ERC20TokenEvents,
blockRange: BlockRange,
indexFilterValues: IndexedFilterValues,
): Promise<Array<LogWithDecodedArgs<ArgsType>>> {
assert.isETHAddressHex('tokenAddress', tokenAddress);
assert.doesBelongToStringEnum('eventName', eventName, ERC20TokenEvents);
assert.doesConformToSchema('blockRange', blockRange, schemas.blockRangeSchema);
assert.doesConformToSchema('indexFilterValues', indexFilterValues, schemas.indexFilterValuesSchema);
const normalizedTokenAddress = tokenAddress.toLowerCase();
const logs = await this._getLogsAsync<ArgsType>(
normalizedTokenAddress,
eventName,
blockRange,
indexFilterValues,
ERC20Token.compilerOutput.abi,
);
return logs;
}
// HACK: We don't want this method to be visible to the other units within that package but not to the end user.
// TS doesn't give that possibility and therefore we make it private and access it over an any cast. Because of that tslint sees it as unused.
// tslint:disable-next-line:no-unused-variable
private _invalidateContractInstances(): void {
this.unsubscribeAll();
this._tokenContractsByAddress = {};
}
private async _getTokenContractAsync(tokenAddress: string): Promise<ERC20TokenContract> {
const normalizedTokenAddress = tokenAddress.toLowerCase();
let tokenContract = this._tokenContractsByAddress[normalizedTokenAddress];
if (!_.isUndefined(tokenContract)) {
return tokenContract;
}
// TODO(albrow): Do we really still need this check? The default error
// looks okay to me.
const doesContractExist = await this._web3Wrapper.doesContractExistAtAddressAsync(tokenAddress);
if (!doesContractExist) {
throw new Error(ContractWrappersError.ERC20TokenContractDoesNotExist);
}
const contractInstance = new ERC20TokenContract(
this.abi,
normalizedTokenAddress,
this._web3Wrapper.getProvider(),
this._web3Wrapper.getContractDefaults(),
);
tokenContract = contractInstance;
this._tokenContractsByAddress[normalizedTokenAddress] = tokenContract;
return tokenContract;
}
}