Trade a Prediction Market Outcome Token

import "dotenv/config";
import {
  Connection,
  Keypair,
  VersionedTransaction,
} from "@solana/web3.js";
import bs58 from "bs58";

const TRADE_API = process.env.DFLOW_TRADE_API_URL!;
const API_KEY = process.env.DFLOW_API_KEY; // Not needed with dev endpoints
const USDC_MINT = process.env.DFLOW_SETTLEMENT_MINT!;
const OUTCOME_TOKEN_MINT = "REPLACE_ME"; // YES or NO mint from /build/recipes/prediction-markets/discover-markets
const BUY_AMOUNT = 1_000_000; // $1 USDC (6 decimals)
const SLIPPAGE_BPS = 50; // 0.5%

const connection = new Connection(process.env.SOLANA_RPC_URL!, "confirmed");
const keypair = Keypair.fromSecretKey(
  bs58.decode(process.env.SOLANA_PRIVATE_KEY!)
);

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

const params = new URLSearchParams({
  inputMint: USDC_MINT,
  outputMint: OUTCOME_TOKEN_MINT,
  amount: BUY_AMOUNT.toString(),
  slippageBps: SLIPPAGE_BPS.toString(),
  userPublicKey: keypair.publicKey.toBase58(),
});

const orderResponse = await fetch(`${TRADE_API}/order?${params}`, {
  headers,
}).then((r) => r.json());

const tx = VersionedTransaction.deserialize(
  Buffer.from(orderResponse.transaction, "base64")
);
tx.sign([keypair]);

const signature = await connection.sendTransaction(tx);
console.log(`Open transaction sent: ${signature}`);

const statusParams = new URLSearchParams({
  signature,
  lastValidBlockHeight: orderResponse.lastValidBlockHeight.toString(),
});

let status: string | undefined;
let fills: any[] = [];

do {
  const statusResponse = await fetch(
    `${TRADE_API}/order-status?${statusParams}`,
    { headers }
  ).then((r) => r.json());

  status = statusResponse.status;
  fills = statusResponse.fills ?? [];
  console.log(`Order status: ${status}`, statusResponse);

  if (status === "pending" || status === "open" || status === "pendingClose") {
    await new Promise((resolve) => setTimeout(resolve, 2000));
  }
} while (
  status === "pending" ||
  status === "open" ||
  status === "pendingClose"
);

const explorerUrl = (sig: string) => `https://orbmarkets.io/tx/${sig}`;
const openTxUrl = explorerUrl(signature);

switch (status) {
  case "closed":
    if (fills.length > 0) {
      console.log(`Success: trade filled with ${fills.length} fill(s)`);
      for (const fill of fills) {
        console.log(`  Fill: ${explorerUrl(fill.signature)}`);
      }
    } else {
      console.log(`Failed: order closed without any fills`);
      console.log(`  Open tx: ${openTxUrl}`);
    }
    break;
  case "failed":
    console.log(`Failed: order failed to execute`);
    console.log(`  Open tx: ${openTxUrl}`);
    break;
  case "expired":
    console.log(`Failed: order expired before fill`);
    console.log(`  Open tx: ${openTxUrl}`);
    break;
  default:
    console.log(`Failed: order ended in unexpected status: ${status}`);
    console.log(`  Open tx: ${openTxUrl}`);
}