SwapRate SDK Release: Example

trader.ts

import { Api, Utils } from '@opiumteam/swaprate-js'
import { PostOrdersFormRequestBody, PayReceiveType, AggregateType } from '@opiumteam/swaprate-js/lib/Utils/types'

const api = new Api()

// Define type of product we want to find: AAVE SUPPLY rate
const type = Utils.types.ProductType.AAVE
const subtype  = Utils.types.ProductSubtype.SUPPLY
const tokenTitle = 'DAI'

// Define type of orders we want to pick up: receive fixed >= 3%
const quoteGte = 0.03
// Define order: 1000 DAI nominal order (10% -> 100 DAI margin)
const nominal = 1000

async function findTokenAndMaturity() {
  const config = await api.getMetaConfig()

  // Find DAI's address
  const tokenAddress = config.supportedTokens.find(token => token.title === tokenTitle).address
  
  // Get 3rd month from now
  const maturity = config.supportedMaturities[2]

  return {
    tokenAddress,
    maturity
  }
}

async function findProduct(tokenAddress: string) {
  // Get all products
  const products = await api.getProducts()

  // Find the one we need
  return products.find(product => product.token === tokenAddress && product.subtype === subtype && product.type === type)
}

async function signMessage(message: any) {
  /**
   * Sign received blockchain message
   * 
   * You can sign it using:
   * 1) Web3
   *    web3.provider.eth.signTypedData(message)
   * 2) Utils and Private key (below)
   */
   const privateKey = Buffer.from('0x00112233', 'hex')
   return Utils.signMessage({ data: message, privateKey })
}

async function login() {
  // Get login data
  const loginData = await api.getAuthLoginData()

  // Sign login data
  const signature = await signMessage(loginData.data)

  const publicKey = '0x12345679abcdef...'

  // Form access token from login data, address and signature
  return Utils.formAccessToken({ ttl: loginData.ttl, address: publicKey, signature })
}

async function placeOrder(productId: string, quote: number, maturity: number) {
  // Get access token
  const accessToken = await login()

  // Prepare order
  const order: PostOrdersFormRequestBody = {
    productId,
    pay: {
      type: PayReceiveType.FLOATING,
      rate: null
    },
    receive: {
      type: PayReceiveType.FIXED,
      rate: quote
    },
    nominal,
    maturity,
    partialFill: true,
    aggregate: AggregateType.NONE
  }

  // Post order in the orderbook and receive blockchain message for signing
  const formedOrder = await api.postOrderForm(order, accessToken)
  
  // Sign order
  const signature = await signMessage(formedOrder.orderToSign)

  // Post signed order
  await api.postOrderSign({
    formedOrderId: formedOrder.formedOrderId,
    signature
  }, accessToken)
}

async function start() {
  /**
   * Retrieve SwapRate configuration and get the DAI's address and maturity of swaps in 3 month
   */
  const { tokenAddress, maturity } = await findTokenAndMaturity()

  /**
   * Find product with DAI token
   */
  const product = await findProduct(tokenAddress)

  /**
   * Connect to charts (curves) updates to react on changes in the market
   * 
   * 1) Setup reaction function `onCharts`
   * 2) Subscribe to changes
   */
  api.onCharts(charts => {
    // Find quote for the desired maturity
    const quote = charts.d.receiveFixed.find(data => data.timestamp === maturity).value
    
    // If current quote on product is more than or equal desired, place an order to pick it up
    if (quote >= quoteGte) {
      placeOrder(product.productId, quote, maturity)
    }
  })
  api.subscribeCharts(product.productId)
}

// Start bot
start()