🤖Swaps

This explains how to use the aiis.dev swap endpoint for preparing unsigned Solana transactions to swap tokens using our bonding curve. The route supports two operations: a buy swap (wrapping SOL into WSOL and executing a buy instruction) and a sell swap (executing a sell instruction and cleaning up WSOL).

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How It Works

1. Account Setup and Preparation

   • Associated Token Accounts: The route derives and, if necessary, creates the user’s WSOL and target token accounts.

   • WSOL Account Top-Up and Sync: For buy operations, the code calculates whether additional lamports (including a fee buffer) are needed to top up the WSOL account and then syncs the account to update its wrapped SOL balance.

   • Tip Transfer: A jito tip transfer instruction is added at the start to send a small fee for faster landing.

   • Bonding Curve Instruction: Depending on the route ("buy" or "sell"), the corresponding bonding curve instruction is appended.

   • Cleanup: For sell operations, the WSOL account is closed after the swap.

2. Transaction Building

   • All instructions are assembled into a versioned transaction.

   • The transaction is serialized to a base64-encoded string and returned to the client for signing. The server never signs transactions, ensuring that private keys remain secure on the client side.

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How to Use

Endpoint

• Method: POST

• Path: /swap/prepare

Request Payload Schema

{
  "route": "buy" or "sell",
  "lamports": "<amount as string>",
  "mint": "<token mint address>",
  "userPublicKey": "<user's wallet public key>"
}

• route: Specifies the swap type. Use "buy" for buying tokens or "sell" for selling.

• lamports: The amount (in lamports) involved in the swap, provided as a string.

• mint: The mint address of the token being swapped.

• userPublicKey: The user's wallet public key.

Example Request:

curl -X POST https://api.aiis.dev/v2/swap/prepare \
-H "Content-Type: application/json" \
-d '{
  "route": "buy",
  "lamports": "1000000",
  "mint": "So11111111111111111111111111111111111111112",
  "userPublicKey": "YourPublicKeyHere"
}'

Example Response:

{
  "unsignedTx": "BASE64_ENCODED_TRANSACTION_STRING"
}

• unsignedTx: This is the unsigned versioned transaction encoded in base64. The client is expected to sign this transaction before submitting it to the blockchain.

Integration:

import axios from "axios";
import { Connection, VersionedTransaction, Keypair, clusterApiUrl } from "@solana/web3.js";
import { readFileSync } from "fs";

(async () => {
  // Load private key from file (ensure this file is secured!)
  const secret = JSON.parse(readFileSync("path/to/secret-key.json", "utf8"));
  const keypair = Keypair.fromSecretKey(new Uint8Array(secret));

  // Define parameters for the swap
  const API_URL = "https://api.aiis.dev/v2/swap/prepare"; // Your swap route endpoint
  const params = {
    route: "buy",
    lamports: "1000000", // Amount in lamports as a string
    mint: "TokenMintPublicKeyHere",
    userPublicKey: keypair.publicKey.toBase58(),
  };

  // Fetch unsigned transaction from the swap route
  const { data: { unsignedTx } } = await axios.post(API_URL, params);
  if (!unsignedTx) throw new Error("No unsigned transaction returned");

  // Deserialize and sign the transaction
  const tx = VersionedTransaction.deserialize(Buffer.from(unsignedTx, "base64"));
  await keypair.signTransaction(tx);

  // Send the signed transaction
  const connection = new Connection(clusterApiUrl("devnet"), "processed");
  const txId = await connection.sendRawTransaction(tx.serialize());
  console.log("Transaction sent, txid:", txId);
})();