70 lines
2.0 KiB
JavaScript
70 lines
2.0 KiB
JavaScript
|
const CoinGecko = require('coingecko-api')
|
||
|
|
const fetch = require('node-fetch')
|
||
|
|
const { gasOracleUrls, defaultGasPrice } = require('../config')
|
||
|
|
const { toWei } = require('web3-utils')
|
||
|
|
const { tokens } = require('../config')
|
||
|
|
|
||
|
|
|
||
|
|
class Fetcher {
|
||
|
|
constructor(web3) {
|
||
|
|
this.web3 = web3
|
||
|
|
this.ethPrices = {
|
||
|
|
dai: '6700000000000000' // 0.0067
|
||
|
|
}
|
||
|
|
this.gasPrices = {
|
||
|
|
fast: defaultGasPrice
|
||
|
|
}
|
||
|
|
}
|
||
|
|
async fetchPrices() {
|
||
|
|
try {
|
||
|
|
const CoinGeckoClient = new CoinGecko()
|
||
|
|
const price = await CoinGeckoClient.simple.fetchTokenPrice({
|
||
|
|
contract_addresses: tokens,
|
||
|
|
vs_currencies: 'eth',
|
||
|
|
assetPlatform: 'ethereum'
|
||
|
|
})
|
||
|
|
const addressToSymbol = {
|
||
|
|
'0x6b175474e89094c44da98b954eedeac495271d0f': 'dai'
|
||
|
|
}
|
||
|
|
this.ethPrices = Object.entries(price.data).reduce((acc, token) => {
|
||
|
|
if (token[1].eth) {
|
||
|
|
acc[addressToSymbol[token[0]]] = toWei(token[1].eth.toString())
|
||
|
|
}
|
||
|
|
return acc
|
||
|
|
}, {})
|
||
|
|
setTimeout(() => this.fetchPrices(), 1000 * 30)
|
||
|
|
} catch(e) {
|
||
|
|
setTimeout(() => this.fetchPrices(), 1000 * 30)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
async fetchGasPrice({ oracleIndex = 0 } = {}) {
|
||
|
|
oracleIndex = (oracleIndex + 1) % gasOracleUrls.length
|
||
|
|
try {
|
||
|
|
const response = await fetch(gasOracleUrls[oracleIndex])
|
||
|
|
if (response.status === 200) {
|
||
|
|
const json = await response.json()
|
||
|
|
|
||
|
|
if (json.slow) {
|
||
|
|
this.gasPrices.low = Number(json.slow)
|
||
|
|
}
|
||
|
|
if (json.safeLow) {
|
||
|
|
this.gasPrices.low = Number(json.safeLow)
|
||
|
|
}
|
||
|
|
if (json.standard) {
|
||
|
|
this.gasPrices.standard = Number(json.standard)
|
||
|
|
}
|
||
|
|
if (json.fast) {
|
||
|
|
this.gasPrices.fast = Number(json.fast)
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
throw Error('Fetch gasPrice failed')
|
||
|
|
}
|
||
|
|
setTimeout(() => this.fetchGasPrice({ oracleIndex }), 15000)
|
||
|
|
} catch (e) {
|
||
|
|
setTimeout(() => this.fetchGasPrice({ oracleIndex }), 15000)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
module.exports = Fetcher
|