First commit

.env

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+INFURA_API_KEY: 
+INTERVAL: 
+NETWORK: 
+FACTORY_ADDRESS: 
+QUOTER_ADDRESS: 
+TOKEN_IN_ADDRESS: 
+TOKEN_OUT_ADDRESS: 

.gitignore

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+node_modules
+.history

README.md

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+# Uniswap Prices Monitor
+
+This project includes a bot written in Node.js that monitors the prices of a specific pair on Uniswap.
+
+## Prerequisites
+
+- Node.js v18.17.0 or greater
+
+## Installation
+
+- npm install
+
+## Enviroment variables
+
+- Make sure to setup an Infura API Key on: https://www.infura.io/
+- Then finally make sure to fill in the environment variables on the .env file
+
+Example:
+
+INFURA_API_KEY: .... // YOUR INFURA API KEY
+INTERVAL: 300000 // 5 Minutes  
+NETWORK: goerli // NETWORK NAME
+FACTORY_ADDRESS: // POOL FACTORY CONTRACT ADDRESS - https://docs.uniswap.org/contracts/v3/reference/deployments
+QUOTER_ADDRESS: // QUOTE CONTRACT ADDRESS - https://docs.uniswap.org/contracts/v3/reference/deployments
+TOKEN_IN_ADDRESS: 0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2 // WETH
+TOKEN_OUT_ADDRESS: 0xdac17f958d2ee523a2206206994597c13d831ec7 // USDT
+
+## Initialization
+
+- npm start
+
+## Disclaimer
+
+The bot has been inspired by the following article:
+
+https://www.luiztools.com.br/post/como-monitorar-precos-de-criptomoedas-na-uniswap-v3/
+
+Thanks to Luiz Tools! :)

index.js

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+require("dotenv").config();
+
+const { INTERVAL, FACTORY_ADDRESS, QUOTER_ADDRESS, TOKEN_IN_ADDRESS, TOKEN_OUT_ADDRESS, NETWORK, INFURA_API_KEY } = process.env;
+
+const { ChainId, Token } = require("@uniswap/sdk-core");
+const WETH_TOKEN = new Token(ChainId.MAINNET, TOKEN_IN_ADDRESS, 18, 'WETH', 'Wrapped Ether');
+const USDT_TOKEN = new Token(ChainId.MAINNET, TOKEN_OUT_ADDRESS, 6, 'USDT', 'Tether');
+
+const { ethers } = require("ethers");
+const provider = new ethers.InfuraProvider(NETWORK, INFURA_API_KEY);
+
+async function preparationCycle() {
+
+    const { computePoolAddress, FeeAmount } = require("@uniswap/v3-sdk")
+    const currentPoolAddress = computePoolAddress({
+        factoryAddress: FACTORY_ADDRESS,
+        tokenA: WETH_TOKEN,
+        tokenB: USDT_TOKEN,
+        fee: FeeAmount.MEDIUM,
+    })
+
+    const IUniswapV3PoolABI = require("@uniswap/v3-core/artifacts/contracts/interfaces/IUniswapV3Pool.sol/IUniswapV3Pool.json");
+    const poolContract = new ethers.Contract(currentPoolAddress, IUniswapV3PoolABI.abi, provider);
+    const result = getTokenOrder(TOKEN_IN_ADDRESS, TOKEN_OUT_ADDRESS);
+
+    result.fee = await poolContract.fee();
+
+    return result;
+}
+
+
+function getTokenOrder(tokenIn, tokenOut) {
+    if (ethers.toBigInt(tokenIn) <= ethers.toBigInt(tokenOut))
+        return { token0: tokenIn, token1: tokenOut };
+    else
+        return { token0: tokenOut, token1: tokenIn };
+}
+
+
+async function executionCycle(token0, token1, fee) {
+    const Quoter = require("@uniswap/v3-periphery/artifacts/contracts/lens/Quoter.sol/Quoter.json");
+    const quoterContract = new ethers.Contract(QUOTER_ADDRESS, Quoter.abi, provider);
+    const quotedAmountOut = await quoterContract.quoteExactInputSingle.staticCall(
+        token0,
+        token1,
+        fee,
+        ethers.parseEther("1"),
+        0
+    )
+
+    console.log("WETH 1 is equals to USDT " + ethers.formatUnits(quotedAmountOut, 6));
+}
+
+(async () => {
+    console.log("Running");
+    const { token0, token1, fee } = await preparationCycle();
+
+    setInterval(() => executionCycle(token0, token1, fee), INTERVAL);
+
+    executionCycle(token0, token1, fee);
+})();