Improve README and add comments

Author: soos3d

README.md

@@ -1,6 +1,30 @@
+<img width="1200" alt="Labs" src="https://user-images.githubusercontent.com/99700157/213291931-5a822628-5b8a-4768-980d-65f324985d32.png">
+
+<p>
+ <h3 align="center">Chainstack is the leading suite of services connecting developers with Web3 infrastructure</h3>
+</p>
+
+<p align="center">
+  <a target="_blank" href="https://chainstack.com/build-better-with-ethereum/"><img src="https://github.com/soos3d/blockchain-badges/blob/main/protocols_badges/Ethereum.svg" /></a>&nbsp;  
+  <a target="_blank" href="https://chainstack.com/build-better-with-bnb-smart-chain/"><img src="https://github.com/soos3d/blockchain-badges/blob/main/protocols_badges/BNB.svg" /></a>&nbsp;
+  <a target="_blank" href="https://chainstack.com/build-better-with-polygon/"><img src="https://github.com/soos3d/blockchain-badges/blob/main/protocols_badges/Polygon.svg" /></a>&nbsp;
+  <a target="_blank" href="https://chainstack.com/build-better-with-avalanche/"><img src="https://github.com/soos3d/blockchain-badges/blob/main/protocols_badges/Avalanche.svg" /></a>&nbsp;
+  <a target="_blank" href="https://chainstack.com/build-better-with-solana/"><img src="https://github.com/soos3d/blockchain-badges/blob/main/protocols_badges/Solana.svg" /></a>&nbsp;
+</p>
+
+<p align="center">
+  <a target="_blank" href="https://chainstack.com/protocols/">Supported protocols</a> •
+  <a target="_blank" href="https://chainstack.com/blog/">Chainstack blog</a> •
+  <a target="_blank" href="https://docs.chainstack.com/quickstart/">Chainstack docs</a> •
+  <a target="_blank" href="https://docs.chainstack.com/quickstart/">Blockchain API reference</a> •
+  <a target="_blank" href="https://console.chainstack.com/user/account/create">Start for free</a>
+</p>
+
 # Raydium SDK Swap Example
 
-This project demonstrates how to perform a token swap on the Solana blockchain using Raydium's protocol. The example specifically illustrates swapping SOL (native Solana token) for USDC (a stablecoin).
+This project demonstrates how to perform a token swap on the Solana blockchain using Raydium and Chainstack. The example specifically illustrates swapping SOL (native Solana token) for USDC (a stablecoin).
+
+> Find the full guide on the Chainstack Developer Portal.
 
 ## Features
 
@@ -13,10 +37,19 @@ This project demonstrates how to perform a token swap on the Solana blockchain u
 
 Before you begin, ensure you have met the following requirements:
 
-- Node.js installed (v14 or above recommended)
+- Node.js installed (v18 or above recommended)
+- Yarn
 - A Solana wallet with some SOL for testing the swap
 - An environment file (.env) with your RPC URL and WALLET_PRIVATE_KEY
 
+## Chainstack Solana node
+
+Deploy a Solana node on Chainstack; the following steps will guide you:
+
+1. [Sign up with Chainstack](https://console.chainstack.com/user/account/create).
+2. [Deploy a node](https://docs.chainstack.com/docs/manage-your-networks#join-a-public-network).
+3. [View node access and credentials](https://docs.chainstack.com/docs/manage-your-node#view-node-access-and-credentials).
+
 ## Environment variables
 
 Add your RPC endoint and private key to a `.env` file:

src/RaydiumSwap.ts

@@ -16,27 +16,45 @@ import bs58 from 'bs58'
 import 'dotenv/config';
 import { swapConfig } from './swapConfig'; // Import the configuration
 
-
+/**
+ * Class representing a Raydium Swap operation.
+ */
 class RaydiumSwap {
   allPoolKeysJson: LiquidityPoolJsonInfo[]
   connection: Connection
   wallet: Wallet
 
+    /**
+   * Create a RaydiumSwap instance.
+   * @param {string} RPC_URL - The RPC URL for connecting to the Solana blockchain.
+   * @param {string} WALLET_PRIVATE_KEY - The private key of the wallet in base58 format.
+   */
   constructor(RPC_URL: string, WALLET_PRIVATE_KEY: string) {
     this.connection = new Connection(process.env.RPC_URL
       , { commitment: 'confirmed' })
-    this.wallet = new Wallet(Keypair.fromSecretKey(Uint8Array.from(bs58.decode(process.env.WALLET_PRIVATE_KEY))))//base58.decode(WALLET_PRIVATE_KEY)))
+    this.wallet = new Wallet(Keypair.fromSecretKey(Uint8Array.from(bs58.decode(process.env.WALLET_PRIVATE_KEY))))
   }
 
+   /**
+   * Loads all the pool keys available from a JSON configuration file.
+   * @async
+   * @returns {Promise<void>}
+   */
   async loadPoolKeys() {
-    const liquidityJsonResp = await fetch(swapConfig.liquidityFile); //https://pastebin.com/raw/CHPMmnDh
+    const liquidityJsonResp = await fetch(swapConfig.liquidityFile);
     if (!liquidityJsonResp.ok) return []
     const liquidityJson = (await liquidityJsonResp.json()) as { official: any; unOfficial: any }
     const allPoolKeysJson = [...(liquidityJson?.official ?? []), ...(liquidityJson?.unOfficial ?? [])]
 
     this.allPoolKeysJson = allPoolKeysJson
   }
 
+    /**
+   * Finds pool information for the given token pair.
+   * @param {string} mintA - The mint address of the first token.
+   * @param {string} mintB - The mint address of the second token.
+   * @returns {LiquidityPoolKeys | null} The liquidity pool keys if found, otherwise null.
+   */
   findPoolInfoForTokens(mintA: string, mintB: string) {
     const poolData = this.allPoolKeysJson.find(
       (i) => (i.baseMint === mintA && i.quoteMint === mintB) || (i.baseMint === mintB && i.quoteMint === mintA)
@@ -47,6 +65,11 @@ class RaydiumSwap {
     return jsonInfo2PoolKeys(poolData) as LiquidityPoolKeys
   }
 
+    /**
+   * Retrieves token accounts owned by the wallet.
+   * @async
+   * @returns {Promise<TokenAccount[]>} An array of token accounts.
+   */
   async getOwnerTokenAccounts() {
     const walletTokenAccount = await this.connection.getTokenAccountsByOwner(this.wallet.publicKey, {
       programId: TOKEN_PROGRAM_ID,
@@ -59,6 +82,17 @@ class RaydiumSwap {
     }))
   }
 
+    /**
+   * Builds a swap transaction.
+   * @async
+   * @param {string} toToken - The mint address of the token to receive.
+   * @param {number} amount - The amount of the token to swap.
+   * @param {LiquidityPoolKeys} poolKeys - The liquidity pool keys.
+   * @param {number} [maxLamports=100000] - The maximum lamports to use for transaction fees.
+   * @param {boolean} [useVersionedTransaction=true] - Whether to use a versioned transaction.
+   * @param {'in' | 'out'} [fixedSide='in'] - The fixed side of the swap ('in' or 'out').
+   * @returns {Promise<Transaction | VersionedTransaction>} The constructed swap transaction.
+   */
   async getSwapTransaction(
     toToken: string,
     // fromToken: string,
@@ -121,6 +155,12 @@ class RaydiumSwap {
     return legacyTransaction
   }
 
+    /**
+   * Sends a legacy transaction.
+   * @async
+   * @param {Transaction} tx - The transaction to send.
+   * @returns {Promise<string>} The transaction ID.
+   */
   async sendLegacyTransaction(tx: Transaction) {
     const txid = await this.connection.sendTransaction(tx, [this.wallet.payer], {
       skipPreflight: true,
@@ -130,6 +170,12 @@ class RaydiumSwap {
     return txid
   }
 
+    /**
+   * Sends a versioned transaction.
+   * @async
+   * @param {VersionedTransaction} tx - The versioned transaction to send.
+   * @returns {Promise<string>} The transaction ID.
+   */
   async sendVersionedTransaction(tx: VersionedTransaction) {
     const txid = await this.connection.sendTransaction(tx, {
       skipPreflight: true,
@@ -139,18 +185,35 @@ class RaydiumSwap {
     return txid
   }
 
+ /**
+   * Simulates a versioned transaction.
+   * @async
+   * @param {VersionedTransaction} tx - The versioned transaction to simulate.
+   * @returns {Promise<any>} The simulation result.
+   */
   async simulateLegacyTransaction(tx: Transaction) {
     const txid = await this.connection.simulateTransaction(tx, [this.wallet.payer])
 
     return txid
   }
 
+    /**
+   * Simulates a versioned transaction.
+   * @async
+   * @param {VersionedTransaction} tx - The versioned transaction to simulate.
+   * @returns {Promise<any>} The simulation result.
+   */
   async simulateVersionedTransaction(tx: VersionedTransaction) {
     const txid = await this.connection.simulateTransaction(tx)
 
     return txid
   }
 
+    /**
+   * Gets a token account by owner and mint address.
+   * @param {PublicKey} mint - The mint address of the token.
+   * @returns {TokenAccount} The token account.
+   */
   getTokenAccountByOwnerAndMint(mint: PublicKey) {
     return {
       programId: TOKEN_PROGRAM_ID,
@@ -162,6 +225,14 @@ class RaydiumSwap {
     } as unknown as TokenAccount
   }
 
+    /**
+   * Calculates the amount out for a swap.
+   * @async
+   * @param {LiquidityPoolKeys} poolKeys - The liquidity pool keys.
+   * @param {number} rawAmountIn - The raw amount of the input token.
+   * @param {boolean} swapInDirection - The direction of the swap (true for in, false for out).
+   * @returns {Promise<Object>} The swap calculation result.
+   */
   async calcAmountOut(poolKeys: LiquidityPoolKeys, rawAmountIn: number, swapInDirection: boolean) {
     const poolInfo = await Liquidity.fetchInfo({ connection: this.connection, poolKeys })
 

src/swapConfig.ts

@@ -1,12 +1,10 @@
 export const swapConfig = {
-    executeSwap: true, // Send tx when true, simulate tx when false
-    useVersionedTransaction: true,
-    tokenAAmount: 0.01, // Swap 0.01 SOL for USDT in this example
-    tokenAAddress: 'So11111111111111111111111111111111111111112', // Token to swap for the other, SOL in this case
-    tokenBAddress: 'EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v', // USDC address
-    LPpoolAddress: '8HoQnePLqPj4M7PUDzfw8e3Ymdwgc7NLGnaTUapubyvu',
-    maxLamports: 1000000, // Max lamports allowed for fees
-    direction: 'in' as 'in' | 'out', // Swap direction: 'in' or 'out'
-    liquidityFile: 'https://api.raydium.io/v2/sdk/liquidity/mainnet.json'
-  };
-  
+  executeSwap: false, // Send tx when true, simulate tx when false
+  useVersionedTransaction: true,
+  tokenAAmount: 0.01, // Swap 0.01 SOL for USDT in this example
+  tokenAAddress: "So11111111111111111111111111111111111111112", // Token to swap for the other, SOL in this case
+  tokenBAddress: "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v", // USDC address
+  maxLamports: 1000000, // Max lamports allowed for fees
+  direction: "in" as "in" | "out", // Swap direction: 'in' or 'out'
+  liquidityFile: "https://api.raydium.io/v2/sdk/liquidity/mainnet.json",
+};