aboutsummaryrefslogtreecommitdiffstats
path: root/src/contract_wrappers/token_wrapper.ts
blob: 91af223e4f3ecd00cee85edfdbc9d8b8f9f4e7cc (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
import * as _ from 'lodash';
import * as BigNumber from 'bignumber.js';
import {SchemaValidator, schemas} from '0x-json-schemas';
import {Web3Wrapper} from '../web3_wrapper';
import {assert} from '../utils/assert';
import {utils} from '../utils/utils';
import {eventUtils} from '../utils/event_utils';
import {constants} from '../utils/constants';
import {ContractWrapper} from './contract_wrapper';
import {AbiDecoder} from '../utils/abi_decoder';
import {artifacts} from '../artifacts';
import {
    TokenContract,
    ZeroExError,
    TokenEvents,
    IndexedFilterValues,
    SubscriptionOpts,
    CreateContractEvent,
    ContractEventEmitter,
    ContractEventObj,
    MethodOpts,
    LogWithDecodedArgs,
    RawLog,
} from '../types';

const ALLOWANCE_TO_ZERO_GAS_AMOUNT = 47155;

/**
 * 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 Proxy smart contract.
 */
export class TokenWrapper extends ContractWrapper {
    public UNLIMITED_ALLOWANCE_IN_BASE_UNITS = constants.UNLIMITED_ALLOWANCE_IN_BASE_UNITS;
    private _tokenContractsByAddress: {[address: string]: TokenContract};
    private _tokenLogEventEmitters: ContractEventEmitter[];
    private _tokenTransferProxyContractAddressFetcher: () => Promise<string>;
    constructor(web3Wrapper: Web3Wrapper, abiDecoder: AbiDecoder,
                tokenTransferProxyContractAddressFetcher: () => Promise<string>) {
        super(web3Wrapper, abiDecoder);
        this._tokenContractsByAddress = {};
        this._tokenLogEventEmitters = [];
        this._tokenTransferProxyContractAddressFetcher = tokenTransferProxyContractAddressFetcher;
    }
    /**
     * 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.BigNumber> {
        assert.isETHAddressHex('ownerAddress', ownerAddress);
        assert.isETHAddressHex('tokenAddress', tokenAddress);

        const tokenContract = await this._getTokenContractAsync(tokenAddress);
        const defaultBlock = _.isUndefined(methodOpts) ? undefined : methodOpts.defaultBlock;
        let balance = await tokenContract.balanceOf.callAsync(ownerAddress, 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.
     * @return Transaction hash.
     */
    public async setAllowanceAsync(tokenAddress: string, ownerAddress: string, spenderAddress: string,
                                   amountInBaseUnits: BigNumber.BigNumber): Promise<string> {
        await assert.isSenderAddressAsync('ownerAddress', ownerAddress, this._web3Wrapper);
        assert.isETHAddressHex('spenderAddress', spenderAddress);
        assert.isETHAddressHex('tokenAddress', tokenAddress);
        assert.isBigNumber('amountInBaseUnits', amountInBaseUnits);

        const tokenContract = await this._getTokenContractAsync(tokenAddress);
        // Hack: for some reason default estimated gas amount causes `base fee exceeds gas limit` exception
        // on testrpc. Probably related to https://github.com/ethereumjs/testrpc/issues/294
        // TODO: Debug issue in testrpc and submit a PR, then remove this hack
        const networkIdIfExists = await this._web3Wrapper.getNetworkIdIfExistsAsync();
        const gas = networkIdIfExists === constants.TESTRPC_NETWORK_ID ? ALLOWANCE_TO_ZERO_GAS_AMOUNT : undefined;
        const txHash = await tokenContract.approve.sendTransactionAsync(spenderAddress, amountInBaseUnits, {
            from: ownerAddress,
            gas,
        });
        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.
     * @return Transaction hash.
     */
    public async setUnlimitedAllowanceAsync(tokenAddress: string, ownerAddress: string,
                                            spenderAddress: string): Promise<string> {
        const txHash = await this.setAllowanceAsync(
            tokenAddress, ownerAddress, spenderAddress, this.UNLIMITED_ALLOWANCE_IN_BASE_UNITS,
        );
        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.BigNumber> {
        assert.isETHAddressHex('ownerAddress', ownerAddress);
        assert.isETHAddressHex('tokenAddress', tokenAddress);

        const tokenContract = await this._getTokenContractAsync(tokenAddress);
        const defaultBlock = _.isUndefined(methodOpts) ? undefined : methodOpts.defaultBlock;
        let allowanceInBaseUnits = await tokenContract.allowance.callAsync(ownerAddress, spenderAddress, 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.BigNumber> {
        assert.isETHAddressHex('ownerAddress', ownerAddress);
        assert.isETHAddressHex('tokenAddress', tokenAddress);

        const proxyAddress = await this._getTokenTransferProxyAddressAsync();
        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.
     * @return Transaction hash.
     */
    public async setProxyAllowanceAsync(tokenAddress: string, ownerAddress: string,
                                        amountInBaseUnits: BigNumber.BigNumber): Promise<string> {
        assert.isETHAddressHex('ownerAddress', ownerAddress);
        assert.isETHAddressHex('tokenAddress', tokenAddress);
        assert.isBigNumber('amountInBaseUnits', amountInBaseUnits);

        const proxyAddress = await this._getTokenTransferProxyAddressAsync();
        const txHash = await this.setAllowanceAsync(tokenAddress, ownerAddress, proxyAddress, amountInBaseUnits);
        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.
     * @return Transaction hash.
     */
    public async setUnlimitedProxyAllowanceAsync(tokenAddress: string, ownerAddress: string): Promise<string> {
        const txHash = await this.setProxyAllowanceAsync(
            tokenAddress, ownerAddress, this.UNLIMITED_ALLOWANCE_IN_BASE_UNITS,
        );
        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.
     * @return Transaction hash.
     */
    public async transferAsync(tokenAddress: string, fromAddress: string, toAddress: string,
                               amountInBaseUnits: BigNumber.BigNumber): Promise<string> {
        assert.isETHAddressHex('tokenAddress', tokenAddress);
        await assert.isSenderAddressAsync('fromAddress', fromAddress, this._web3Wrapper);
        assert.isETHAddressHex('toAddress', toAddress);
        assert.isBigNumber('amountInBaseUnits', amountInBaseUnits);

        const tokenContract = await this._getTokenContractAsync(tokenAddress);

        const fromAddressBalance = await this.getBalanceAsync(tokenAddress, fromAddress);
        if (fromAddressBalance.lessThan(amountInBaseUnits)) {
            throw new Error(ZeroExError.InsufficientBalanceForTransfer);
        }

        const txHash = await tokenContract.transfer.sendTransactionAsync(toAddress, amountInBaseUnits, {
            from: fromAddress,
        });
        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.
     * @return Transaction hash.
     */
    public async transferFromAsync(tokenAddress: string, fromAddress: string, toAddress: string,
                                   senderAddress: string, amountInBaseUnits: BigNumber.BigNumber):
                                   Promise<string> {
        assert.isETHAddressHex('tokenAddress', tokenAddress);
        assert.isETHAddressHex('fromAddress', fromAddress);
        assert.isETHAddressHex('toAddress', toAddress);
        await assert.isSenderAddressAsync('senderAddress', senderAddress, this._web3Wrapper);
        assert.isBigNumber('amountInBaseUnits', amountInBaseUnits);

        const tokenContract = await this._getTokenContractAsync(tokenAddress);

        const fromAddressAllowance = await this.getAllowanceAsync(tokenAddress, fromAddress, senderAddress);
        if (fromAddressAllowance.lessThan(amountInBaseUnits)) {
            throw new Error(ZeroExError.InsufficientAllowanceForTransfer);
        }

        const fromAddressBalance = await this.getBalanceAsync(tokenAddress, fromAddress);
        if (fromAddressBalance.lessThan(amountInBaseUnits)) {
            throw new Error(ZeroExError.InsufficientBalanceForTransfer);
        }

        const txHash = await tokenContract.transferFrom.sendTransactionAsync(
            fromAddress, toAddress, amountInBaseUnits,
            {
                from: senderAddress,
            },
        );
        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   subscriptionOpts    Subscriptions options that let you configure the subscription.
     * @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}`
     * @return ContractEventEmitter object
     */
    public async subscribeAsync(tokenAddress: string, eventName: TokenEvents, subscriptionOpts: SubscriptionOpts,
                                indexFilterValues: IndexedFilterValues): Promise<ContractEventEmitter> {
        assert.isETHAddressHex('tokenAddress', tokenAddress);
        assert.doesBelongToStringEnum('eventName', eventName, TokenEvents);
        assert.doesConformToSchema('subscriptionOpts', subscriptionOpts, schemas.subscriptionOptsSchema);
        assert.doesConformToSchema('indexFilterValues', indexFilterValues, schemas.indexFilterValuesSchema);
        const tokenContract = await this._getTokenContractAsync(tokenAddress);
        let createLogEvent: CreateContractEvent;
        switch (eventName) {
            case TokenEvents.Approval:
                createLogEvent = tokenContract.Approval;
                break;
            case TokenEvents.Transfer:
                createLogEvent = tokenContract.Transfer;
                break;
            default:
                throw utils.spawnSwitchErr('TokenEvents', eventName);
        }

        const logEventObj: ContractEventObj = createLogEvent(indexFilterValues, subscriptionOpts);
        const eventEmitter = eventUtils.wrapEventEmitter(logEventObj);
        this._tokenLogEventEmitters.push(eventEmitter);
        return eventEmitter;
    }
    /**
     * Gets historical logs without creating a subscription
     * @param   tokenAddress        An address of the token that emmited the logs.
     * @param   eventName           The token contract event you would like to subscribe to.
     * @param   subscriptionOpts    Subscriptions options that let you configure the subscription.
     * @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(tokenAddress: string, eventName: TokenEvents, subscriptionOpts: SubscriptionOpts,
                              indexFilterValues: IndexedFilterValues): Promise<LogWithDecodedArgs[]> {
        const logs = await this._getLogsAsync(
            tokenAddress, eventName, subscriptionOpts, indexFilterValues, artifacts.TokenArtifact.abi,
        );
        return logs;
    }
    /**
     * Stops watching for all token events
     */
    public async stopWatchingAllEventsAsync(): Promise<void> {
        const stopWatchingPromises = _.map(this._tokenLogEventEmitters,
                                           logEventObj => logEventObj.stopWatchingAsync());
        await Promise.all(stopWatchingPromises);
        this._tokenLogEventEmitters = [];
    }
    private async _invalidateContractInstancesAsync(): Promise<void> {
        await this.stopWatchingAllEventsAsync();
        this._tokenContractsByAddress = {};
    }
    private async _getTokenContractAsync(tokenAddress: string): Promise<TokenContract> {
        let tokenContract = this._tokenContractsByAddress[tokenAddress];
        if (!_.isUndefined(tokenContract)) {
            return tokenContract;
        }
        const contractInstance = await this._instantiateContractIfExistsAsync<TokenContract>(
            artifacts.TokenArtifact, tokenAddress,
        );
        tokenContract = contractInstance as TokenContract;
        this._tokenContractsByAddress[tokenAddress] = tokenContract;
        return tokenContract;
    }
    private async _getTokenTransferProxyAddressAsync(): Promise<string> {
        const tokenTransferProxyContractAddress = await this._tokenTransferProxyContractAddressFetcher();
        return tokenTransferProxyContractAddress;
    }
}