tornado-relayer/src/priceWatcher.js

const Redis = require('ioredis')
const { redisUrl, offchainOracleAddress, oracleRpcUrl } = require('./config')
const { getArgsForOracle, setSafeInterval } = require('./utils')
const redis = new Redis(redisUrl)
const Web3 = require('web3')
const web3 = new Web3(
  new Web3.providers.HttpProvider(oracleRpcUrl, {
    timeout: 200000, // ms
  }),
)

const offchainOracleABI = require('../abis/OffchainOracle.abi.json')

const offchainOracle = new web3.eth.Contract(offchainOracleABI, offchainOracleAddress)
const { tokenAddresses, oneUintAmount, currencyLookup } = getArgsForOracle()

const { toBN } = require('web3-utils')

async function main() {
  try {
    const ethPrices = {}
    for (let i = 0; i < tokenAddresses.length; i++) {
      try {
        const price = await offchainOracle.methods
          .getRate(tokenAddresses[i], '0x0000000000000000000000000000000000000000')
          .call()
        const numerator = toBN(oneUintAmount[i])
        const denominator = toBN(10).pow(toBN(18)) // eth decimals
        const priceFormatted = toBN(price).mul(numerator).div(denominator)

        ethPrices[currencyLookup[tokenAddresses[i]]] = priceFormatted.toString()
      } catch (e) {
        console.error('cant get price of ', tokenAddresses[i])
      }
    }

    await redis.hmset('prices', ethPrices)
    console.log('Wrote following prices to redis', ethPrices)
  } catch (e) {
    console.error('priceWatcher error', e)
  }
}

setSafeInterval(main, 30 * 1000)