Retries and idempotency

import os
import time
import uuid

import requests

API = "https://tradingapi.dev/v1"
HEADERS = {"Authorization": f"Bearer {os.environ['TRADINGAPI_KEY']}"}


def place_order(body: dict, attempts: int = 5) -> dict:
    """Places one order, retrying safely. body must include client_order_id."""
    for attempt in range(attempts):
        try:
            response = requests.post(f"{API}/orders", json=body, headers=HEADERS, timeout=30)
        except requests.RequestException:
            time.sleep(2**attempt)
            continue  # Same body, same client_order_id.
        if response.status_code in (200, 201):
            return response.json()
        error = response.json()["error"]
        if not error["retryable"]:
            raise RuntimeError(f"{error['code']}: {error['message']} {error.get('hint') or ''}")
        time.sleep(2**attempt)
    raise RuntimeError("Gave up; the order may exist. Look it up by client_order_id.")


order = place_order({
    "client_order_id": f"rebalance-{uuid.uuid4()}",  # New ID per new order, created once.
    "market": "ETH",
    "side": "buy",
    "type": "market",
    "value": "20.00",
})
print(order["summary"])

const API = "https://tradingapi.dev/v1";
const headers = {
  Authorization: `Bearer ${process.env.TRADINGAPI_KEY}`,
  "Content-Type": "application/json",
};
const sleep = (ms) => new Promise((resolve) => setTimeout(resolve, ms));

// Places one order, retrying safely. body must include client_order_id.
async function placeOrder(body, attempts = 5) {
  for (let attempt = 0; attempt < attempts; attempt++) {
    let response;
    try {
      response = await fetch(`${API}/orders`, { method: "POST", headers, body: JSON.stringify(body) });
    } catch {
      await sleep(1000 * 2 ** attempt);
      continue; // Same body, same client_order_id.
    }
    if (response.status === 200 || response.status === 201) return response.json();
    const { error } = await response.json();
    if (!error.retryable) throw new Error(`${error.code}: ${error.message} ${error.hint ?? ""}`);
    await sleep(1000 * 2 ** attempt);
  }
  throw new Error("Gave up; the order may exist. Look it up by client_order_id.");
}

const order = await placeOrder({
  client_order_id: `rebalance-${crypto.randomUUID()}`, // New ID per new order, created once.
  market: "ETH",
  side: "buy",
  type: "market",
  value: "20.00",
});
console.log(order.summary);