Added ethers and UniswapV2

.env.example

@@ -1,3 +1,2 @@
 RPC_URL="https://ropsten.infura.io/v3/YOUR_API_KEY"
-PRIVATE_KEY="0x..."
-ACCOUNT="0x..."
+UNISWAPV2_ROUTER_ADDRESS = "0x..."

.gitignore

@@ -2,8 +2,9 @@ npm_modules
 npm_modules/*
 node_modules
 node_modules/*
-.env
+*.env
 logs/*
 logs
 examples/*
 examples
+build

README.md

@@ -0,0 +1,35 @@
+# Price Bot
+This is a simple example of a price bot. 
+
+## Requirements
+- Node 10.x
+
+## Installation
+```
+# create a .env file
+cp .env.example .env
+
+# Fill in the blanks
+nano .env
+
+# Install dependencies
+npm i
+
+```
+
+## Web3 with UniswapV1 and Kyber
+
+Run the command below to use web3 to connect to uniswapV1 and Kyber to get prices. 
+Note that uniswapv1 is no longer under active development, but that doesn't mean there aren't arb opps.
+
+```
+node index.js
+```
+
+## Ethers with UniswapV2 and Kyber
+
+Run the command below to use ethers to connect to uniswapV2 and Kyber to get prices.
+
+```
+node index2.js
+```

index2.js

@@ -0,0 +1,128 @@
+require('dotenv').config()
+
+//http dependencies
+const express = require('express')
+const bodyParser = require('body-parser')
+const http = require('http')
+const moment = require('moment-timezone')
+const numeral = require('numeral')
+const _ = require('lodash')
+const axios = require('axios')
+
+// ethereum dependencies
+const ethers = require('ethers');
+const { parseUnits, formatUnits } = ethers.utils;
+const { legos } = require('@studydefi/money-legos');
+
+// SERVER CONFIG
+const PORT = process.env.PORT || 5000
+const app = express();
+const server = http.createServer(app).listen(PORT, () => console.log(`Listening on ${ PORT }`))
+
+// ETHERS CONFIG
+const provider = new ethers.providers.JsonRpcProvider(process.env.RPC_URL);
+
+// Contracts
+const uniswapV2 = new ethers.Contract(
+    process.env.UNISWAPV2_ROUTER_ADDRESS,
+    [
+      'function getAmountsOut(uint256 amountIn, address[] calldata path) external view returns (uint256[] memory amounts)',
+      'function WETH() external pure returns (address)'
+    ],
+    provider
+  );
+
+const kyber = new ethers.Contract(legos.kyber.network.address, 
+      legos.kyber.network.abi, 
+      provider);
+
+
+async function checkPair(args) {
+  const { inputTokenSymbol, inputTokenAddress, outputTokenSymbol, outputTokenAddress, inputAmount } = args
+
+
+  // calculate uniswap amount
+  const path = [inputTokenAddress, outputTokenAddress];
+  const amounts = await uniswapV2.getAmountsOut(inputAmount, path);
+  const uniswapAmount = amounts[1];
+
+  // calculate kyber amount
+  const { expectedRate, slippageRate } = await kyber.getExpectedRate(inputTokenAddress, outputTokenAddress, inputAmount);
+  const kyberExpectedAmount = expectedRate;
+  const kyberSlippageAmount = slippageRate;
+
+
+
+  console.table([{
+    'Input Token': inputTokenSymbol,
+    'Output Token': outputTokenSymbol,
+    'Input Amount': formatUnits(inputAmount, 18),
+    'Uniswap Return': formatUnits(uniswapAmount, 18),
+    'Kyber Expected Rate': formatUnits(kyberExpectedAmount, 18),
+    'Kyber Min Return': formatUnits(kyberSlippageAmount, 18),
+    'Timestamp': moment().tz('America/Chicago').format(),
+  }])
+}
+
+let priceMonitor
+let monitoringPrice = false
+
+async function monitorPrice() {
+  if(monitoringPrice) {
+    return
+  }
+
+  console.log("Checking prices...")
+  monitoringPrice = true
+
+  try {
+
+    // ADD YOUR CUSTOM TOKEN PAIRS HERE!!!
+
+    const WETH_ADDRESS = await uniswapV2.WETH(); // Uniswap V2 uses wrapped eth
+
+    await checkPair({
+      inputTokenSymbol: 'WETH',
+      inputTokenAddress: WETH_ADDRESS,
+      outputTokenSymbol: 'BAT',
+      outputTokenAddress: legos.erc20.bat.address,
+      inputAmount: parseUnits('1', 18)
+    })
+
+    await checkPair({
+      inputTokenSymbol: 'WETH',
+      inputTokenAddress: WETH_ADDRESS,
+      outputTokenSymbol: 'DAI',
+      outputTokenAddress: '0x6b175474e89094c44da98b954eedeac495271d0f',
+      inputAmount: parseUnits('1', 18)
+    })
+
+    await checkPair({
+      inputTokenSymbol: 'WETH',
+      inputTokenAddress: WETH_ADDRESS,
+      outputTokenSymbol: 'KNC',
+      outputTokenAddress: '0xdd974d5c2e2928dea5f71b9825b8b646686bd200',
+      inputAmount: parseUnits('1', 18)
+    })
+
+    await checkPair({
+      inputTokenSymbol: 'WETH',
+      inputTokenAddress: WETH_ADDRESS,
+      outputTokenSymbol: 'LINK',
+      outputTokenAddress: '0x514910771af9ca656af840dff83e8264ecf986ca',
+      inputAmount: parseUnits('1', 18)
+    })
+
+  } catch (error) {
+    console.error(error)
+    monitoringPrice = false
+    clearInterval(priceMonitor)
+    return
+  }
+
+  monitoringPrice = false
+}
+
+// Check markets every n seconds
+const POLLING_INTERVAL = process.env.POLLING_INTERVAL || 3000 // 3 Seconds
+priceMonitor = setInterval(async () => { await monitorPrice() }, POLLING_INTERVAL)

index3.js

@@ -0,0 +1,95 @@
+require('dotenv').config()
+
+//http dependencies
+const express = require('express')
+const bodyParser = require('body-parser')
+const http = require('http')
+const moment = require('moment-timezone')
+const numeral = require('numeral')
+const _ = require('lodash')
+const axios = require('axios')
+
+// ethereum dependencies
+const ethers = require('ethers');
+const { parseUnits, formatUnits } = ethers.utils;
+const { legos } = require('@studydefi/money-legos');
+
+// SERVER CONFIG
+const PORT = process.env.PORT || 5000
+const app = express();
+const server = http.createServer(app).listen(PORT, () => console.log(`Listening on ${ PORT }`))
+
+// ETHERS CONFIG
+const provider = new ethers.providers.JsonRpcProvider(process.env.RPC_URL);
+
+// Contracts
+const uniswapV2 = new ethers.Contract(
+    process.env.PANCAKE_ROUTER_ADDRESS,
+    [
+      'function getAmountsOut(uint256 amountIn, address[] calldata path) external view returns (uint256[] memory amounts)',
+      'function WETH() external pure returns (address)'
+    ],
+    provider
+  );
+
+
+async function checkPair(args) {
+  const { inputTokenSymbol, inputTokenAddress, outputTokenSymbol, outputTokenAddress, inputAmount } = args
+
+
+  // calculate uniswap amount
+  const path = [inputTokenAddress, outputTokenAddress];
+  const amounts = await uniswapV2.getAmountsOut(inputAmount, path);
+  const uniswapAmount = amounts[1];
+
+
+
+
+  console.table([{
+    'Input Token': inputTokenSymbol,
+    'Output Token': outputTokenSymbol,
+    'Input Amount': formatUnits(inputAmount, 18),
+    'Uniswap Return': formatUnits(uniswapAmount, 18),
+    'Timestamp': moment().tz('America/Chicago').format(),
+  }])
+}
+
+let priceMonitor
+let monitoringPrice = false
+
+async function monitorPrice() {
+  if(monitoringPrice) {
+    return
+  }
+
+  console.log("Checking prices...")
+  monitoringPrice = true
+
+  try {
+
+    // ADD YOUR CUSTOM TOKEN PAIRS HERE!!!
+
+    const WETH_ADDRESS = await uniswapV2.WETH(); // Uniswap V2 uses wrapped eth
+
+    await checkPair({
+      inputTokenSymbol: 'BNB',
+      inputTokenAddress: process.env.BNB_ADDRESS,
+      outputTokenSymbol: 'BUSD',
+      outputTokenAddress: process.env.BUSD_ADDRESS,
+      inputAmount: parseUnits('1', 18)
+    })
+
+
+  } catch (error) {
+    console.error(error)
+    monitoringPrice = false
+    clearInterval(priceMonitor)
+    return
+  }
+
+  monitoringPrice = false
+}
+
+// Check markets every n seconds
+const POLLING_INTERVAL = process.env.POLLING_INTERVAL || 3000 // 3 Seconds
+priceMonitor = setInterval(async () => { await monitorPrice() }, POLLING_INTERVAL)