This will walk you through the process to interact with the Uniswap V3 protocol using the Stardust API/SDK and the ethers library. By following this example, you’ll be able to create, sign, and send a transaction to interact with the Uniswap V3 protocol

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Prerequisites

  • Node.js installed on your system
  • Stardust API key and wallet Id or profile Id
  • dotenv, axios, ethers v6, @uniswap/v3-sdk, and @uniswap/sdk-core libraries

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Setup

  1. Install Dependencies First, you need to install the required dependencies: 
    npm install dotenv axios ethers @uniswap/v3-sdk @uniswap/sdk-core
  2. Create a .env File Create a .env file in your project root directory and add your Stardust API key and profile ID: 
    PROD_SYSTEM_STARDUST_API_KEY=your_stardust_api_key
PROD_SYSTEM_STARDUST_PROFILE_ID=your_stardust_profile_id

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Code Example

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1. Import Libraries and Configure Environment

First, import the necessary libraries and configure your environment using the .env file: 
import dotenv from 'dotenv';
import axios from 'axios';
import { ethers } from 'ethers';

dotenv.config();
This code imports dotenv, axios, and ethers libraries and sets up the environment variables.

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2. Setup Configuration

Next, set up the API key and profile ID from the environment variables: 
const apiKey = process.env.PROD_SYSTEM_STARDUST_API_KEY!;
const profileId = process.env.PROD_SYSTEM_STARDUST_PROFILE_ID!;
Next, set up the RPC provider for the EVM network 
const rpcUrl = '<evm-rpc-network-here>';
const rpcProvider = new ethers.JsonRpcProvider(rpcUrl);

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3. Instantiate the Stardust Ethers V6 signer

Initialize the Stardust SDK, get the wallet, and instantiate the signer: 
 // Initialize Stardust SDK
const sdk = new StardustCustodialSDK(apiKey);

// Get Wallet
const profile = await sdk.getProfile(profileId);
const { wallet } = profile;

const evmAddress = await wallet.evm.getAddress();

// Get V6 Signer
const signer = wallet.ethers.v6.getSigner(rpcProvider);

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4. Creating the Uniswap V3 transaction

Refer to the Uniswap SDK documentation for detailed steps on creating a transaction. Your transaction object should look something like this: 
const tx = {
  data: methodParameters.calldata,
  to: SWAP_ROUTER_ADDRESS,
  value: methodParameters.value,
  from: evmAddress,
  maxFeePerGas: MAX_FEE_PER_GAS,
  maxPriorityFeePerGas: MAX_PRIORITY_FEE_PER_GAS,
}

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5. Send the transaction

Finally, send the transaction using the Ethers V6 Signer, previous instantiated: 
const txResponse = await signer.sendTransaction(tx);
console.log(`Sent tx object ${JSON.stringify(txResponse)}`);

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Conclusion

You have successfully executed a trade on the Uniswap V3 protocol using the Stardust API/SDK and the ethers library. This example demonstrates how to create, sign, and send a transaction to interact with the Uniswap V3 protocol. You can now build more complex trading strategies and applications using this foundation.