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
|
import {
ContractWrappers,
ExchangeCancelEventArgs,
ExchangeCancelUpToEventArgs,
ExchangeEventArgs,
ExchangeEvents,
ExchangeFillEventArgs,
ExchangeWrapper,
} from '@0x/contract-wrappers';
import { Web3ProviderEngine } from '@0x/subproviders';
import { Web3Wrapper } from '@0x/web3-wrapper';
import { LogWithDecodedArgs } from 'ethereum-types';
const BLOCK_FINALITY_THRESHOLD = 10; // When to consider blocks as final. Used to compute default toBlock.
const NUM_BLOCKS_PER_QUERY = 20000; // Number of blocks to query for events at a time.
const EXCHANGE_START_BLOCK = 6271590; // Block number when the Exchange contract was deployed to mainnet.
export class ExchangeEventsSource {
private readonly _exchangeWrapper: ExchangeWrapper;
private readonly _web3Wrapper: Web3Wrapper;
constructor(provider: Web3ProviderEngine, networkId: number) {
this._web3Wrapper = new Web3Wrapper(provider);
const contractWrappers = new ContractWrappers(provider, { networkId });
this._exchangeWrapper = contractWrappers.exchange;
}
public async getFillEventsAsync(
fromBlock?: number,
toBlock?: number,
): Promise<Array<LogWithDecodedArgs<ExchangeFillEventArgs>>> {
return this._getEventsAsync<ExchangeFillEventArgs>(ExchangeEvents.Fill, fromBlock, toBlock);
}
public async getCancelEventsAsync(
fromBlock?: number,
toBlock?: number,
): Promise<Array<LogWithDecodedArgs<ExchangeCancelEventArgs>>> {
return this._getEventsAsync<ExchangeCancelEventArgs>(ExchangeEvents.Cancel, fromBlock, toBlock);
}
public async getCancelUpToEventsAsync(
fromBlock?: number,
toBlock?: number,
): Promise<Array<LogWithDecodedArgs<ExchangeCancelUpToEventArgs>>> {
return this._getEventsAsync<ExchangeCancelUpToEventArgs>(ExchangeEvents.CancelUpTo, fromBlock, toBlock);
}
private async _getEventsAsync<ArgsType extends ExchangeEventArgs>(
eventName: ExchangeEvents,
fromBlock: number = EXCHANGE_START_BLOCK,
toBlock?: number,
): Promise<Array<LogWithDecodedArgs<ArgsType>>> {
const calculatedToBlock =
toBlock === undefined
? (await this._web3Wrapper.getBlockNumberAsync()) - BLOCK_FINALITY_THRESHOLD
: toBlock;
let events: Array<LogWithDecodedArgs<ArgsType>> = [];
for (let currFromBlock = fromBlock; currFromBlock <= calculatedToBlock; currFromBlock += NUM_BLOCKS_PER_QUERY) {
events = events.concat(
await this._getEventsForRangeAsync<ArgsType>(
eventName,
currFromBlock,
Math.min(currFromBlock + NUM_BLOCKS_PER_QUERY - 1, calculatedToBlock),
),
);
}
return events;
}
private async _getEventsForRangeAsync<ArgsType extends ExchangeEventArgs>(
eventName: ExchangeEvents,
fromBlock: number,
toBlock: number,
): Promise<Array<LogWithDecodedArgs<ArgsType>>> {
return this._exchangeWrapper.getLogsAsync<ArgsType>(
eventName,
{
fromBlock,
toBlock,
},
{},
);
}
}
|
