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
|
import * as Web3 from 'web3';
import * as _ from 'lodash';
import promisify = require('es6-promisify');
export class Contract implements Web3.ContractInstance {
public address: string;
public abi: Web3.ContractAbi;
private contract: Web3.ContractInstance;
private defaults: Partial<Web3.TxData>;
// This class instance is going to be populated with functions and events depending on the ABI
// and we don't know their types in advance
[name: string]: any;
constructor(web3ContractInstance: Web3.ContractInstance, defaults: Partial<Web3.TxData>) {
this.contract = web3ContractInstance;
this.address = web3ContractInstance.address;
this.abi = web3ContractInstance.abi;
this.defaults = defaults;
this.populateEvents();
this.populateFunctions();
}
private populateFunctions(): void {
const functionsAbi = _.filter(this.abi, abiPart => abiPart.type === 'function');
_.forEach(functionsAbi, (functionAbi: Web3.MethodAbi) => {
const cbStyleFunction = this.contract[functionAbi.name];
if (functionAbi.constant) {
this[functionAbi.name] = promisify(cbStyleFunction, this.contract);
const cbStyleCallFunction = this.contract[functionAbi.name].call;
this[functionAbi.name].call = promisify(cbStyleCallFunction, this.contract);
} else {
this[functionAbi.name] = this.promisifyWithDefaultParams(cbStyleFunction);
const cbStyleEstimateGasFunction = this.contract[functionAbi.name].estimateGas;
this[functionAbi.name].estimateGas =
promisify(cbStyleEstimateGasFunction, this.contract);
}
});
}
private populateEvents(): void {
const eventsAbi = _.filter(this.abi, abiPart => abiPart.type === 'event');
_.forEach(eventsAbi, (eventAbi: Web3.EventAbi) => {
this[eventAbi.name] = this.contract[eventAbi.name];
});
}
private promisifyWithDefaultParams(fn: (...args: any[]) => void): (...args: any[]) => Promise<any> {
const promisifiedWithDefaultParams = (...args: any[]) => {
const promise = new Promise((resolve, reject) => {
const lastArg = args[args.length - 1];
let txData: Partial<Web3.TxData> = {};
if (_.isObject(lastArg) && !_.isArray(lastArg) && !lastArg.isBigNumber) {
txData = args.pop();
}
txData = {
...txData,
...this.defaults,
};
const callback = (err: Error, data: any) => {
if (_.isNull(err)) {
resolve(data);
} else {
reject(err);
}
};
args.push(txData);
args.push(callback);
fn.apply(this.contract, args);
});
return promise;
};
return promisifiedWithDefaultParams;
}
}
|
