Retry writes safely with Idempotency-Key

import { randomUUID } from "node:crypto";

async function createContact(contact) {
  const key = randomUUID(); // one key for this contact, reused on every retry
  for (let attempt = 0; attempt < 5; attempt++) {
    try {
      const res = await fetch("https://api.meetdarwin.ai/v1/contacts", {
        method: "POST",
        headers: {
          Authorization: `Bearer ${process.env.DARWIN_API_KEY}`,
          "Content-Type": "application/json",
          "Idempotency-Key": key,
        },
        body: JSON.stringify(contact),
      });
      if (res.status === 429 || res.status === 409 || res.status >= 500) {
        const wait = Number(res.headers.get("retry-after")) || 2 ** attempt;
        await new Promise((r) => setTimeout(r, wait * 1000));
        continue;
      }
      return await res.json();
    } catch {
      await new Promise((r) => setTimeout(r, 2 ** attempt * 1000)); // network error: retry with the same key
    }
  }
  throw new Error("Darwin did not answer after 5 attempts");
}

import os, time, uuid, requests

def create_contact(contact):
    key = str(uuid.uuid4())  # one key for this contact, reused on every retry
    for attempt in range(5):
        try:
            res = requests.post(
                "https://api.meetdarwin.ai/v1/contacts",
                json=contact,
                headers={
                    "Authorization": f"Bearer {os.environ['DARWIN_API_KEY']}",
                    "Idempotency-Key": key,
                },
                timeout=30,
            )
        except requests.RequestException:
            time.sleep(2 ** attempt)
            continue
        if res.status_code in (409, 429) or res.status_code >= 500:
            time.sleep(int(res.headers.get("Retry-After", 2 ** attempt)))
            continue
        return res.json()
    raise RuntimeError("Darwin did not answer after 5 attempts")