Submit a transaction to Stellar RPC

import { FeeBumpTransaction, Transaction } from "@stellar/stellar-sdk";
import { Api, Server } from "@stellar/stellar-sdk/rpc";

const RPC_SERVER = "https://soroban-testnet.stellar.org/";
const server = new Server(RPC_SERVER);

const sleep = (ms: number) => new Promise((resolve) => setTimeout(resolve, ms));

// Sends a transaction, then waits until it is in a ledger or has expired.
async function submitTx(
  tx: Transaction | FeeBumpTransaction,
): Promise<Api.GetTransactionResponse> {
  // A transaction can go into a ledger only until its time bound (maxTime).
  const inner = tx instanceof FeeBumpTransaction ? tx.innerTransaction : tx;
  const maxTime = Number(inner.timeBounds?.maxTime ?? 0);
  if (maxTime === 0) {
    throw new Error("Call setTimeout() so that the transaction can expire");
  }

  // TRY_AGAIN_LATER: send the same signed transaction again after a pause.
  let reply = await server.sendTransaction(tx);
  while (
    reply.status === "TRY_AGAIN_LATER" &&
    Number(reply.latestLedgerCloseTime) <= maxTime
  ) {
    await sleep(2000);
    reply = await server.sendTransaction(tx);
  }

  // ERROR: a transaction that is already in a ledger also returns ERROR
  // (txBAD_SEQ) when you send it again, so look it up before you throw.
  if (reply.status === "ERROR") {
    const known = await server.getTransaction(reply.hash);
    if (known.status === Api.GetTransactionStatus.NOT_FOUND) {
      throw reply;
    }
  }

  // Poll until the transaction is in a ledger or has expired.
  // NOT_FOUND means "not in a ledger yet", not "failed".
  while (true) {
    const result = await server.getTransaction(reply.hash);
    switch (result.status) {
      case Api.GetTransactionStatus.SUCCESS:
        return result;
      case Api.GetTransactionStatus.FAILED:
        throw result;
      case Api.GetTransactionStatus.NOT_FOUND:
        // A ledger closed after maxTime, so the transaction can never go
        // into a ledger. Only now is it safe to build a new transaction.
        if (Number(result.latestLedgerCloseTime) > maxTime) {
          throw new Error(`Transaction ${reply.hash} expired`);
        }
        await sleep(1000);
    }
  }
}