Authenticate Requests

import "dotenv/config";

import { Keypair } from "@solana/web3.js";
import bs58 from "bs58";

const DFLOW_TRADE_API_URL = process.env.DFLOW_TRADE_API_URL ?? "https://dev-quote-api.dflow.net";
const DFLOW_API_KEY = process.env.DFLOW_API_KEY; // optional; not needed for dev endpoints
const DFLOW_SETTLEMENT_MINT = process.env.DFLOW_SETTLEMENT_MINT ?? "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v"; // USDC

const SOL_MINT = "So11111111111111111111111111111111111111112";
const amount = 100_000; // 0.0001 SOL (9 decimals)
const slippageBps = 50; // 0.5%

const keypair = Keypair.fromSecretKey(
  bs58.decode(process.env.SOLANA_PRIVATE_KEY ?? "")
);

const headers: HeadersInit = {};
if (DFLOW_API_KEY) headers["x-api-key"] = DFLOW_API_KEY;

const queryParams = new URLSearchParams();
queryParams.append("inputMint", SOL_MINT);
queryParams.append("outputMint", DFLOW_SETTLEMENT_MINT);
queryParams.append("amount", amount.toString());
queryParams.append("slippageBps", slippageBps.toString());
queryParams.append("userPublicKey", keypair.publicKey.toBase58());

const response = await fetch(
  `${DFLOW_TRADE_API_URL}/order?${queryParams.toString()}`,
  { headers }
).then((x) => x.json());

// Reuses DFLOW_TRADE_API_URL, DFLOW_API_KEY, and headers from the GET setup above.
// intentData and openTransaction come from an earlier /intent call.
async function submitIntent(intentData: unknown, openTransaction: { serialize(): Buffer }) {
  const response = await fetch(`${DFLOW_TRADE_API_URL}/submit-intent`, {
    method: "POST",
    headers: { ...headers, "Content-Type": "application/json" },
    body: JSON.stringify({
      quoteResponse: intentData,
      signedOpenTransaction: Buffer.from(openTransaction.serialize()).toString(
        "base64"
      ),
    }),
  });
  return response.json();
}