Errors

import { randomUUID } from 'node:crypto';

const RETRYABLE = new Set([429, 500, 503]);

async function cartaflow(path, { method = 'GET', body, idempotencyKey } = {}) {
  // One key per operation, created once and reused on every attempt.
  const key = idempotencyKey ?? (method === 'POST' ? randomUUID() : undefined);

  for (let attempt = 0; attempt < 5; attempt++) {
    let response;
    try {
      response = await fetch(`https://api.cartaflow.com.br/v1${path}`, {
        method,
        headers: {
          Authorization: `Bearer ${process.env.CARTAFLOW_API_KEY}`,
          ...(body ? { 'Content-Type': 'application/json' } : {}),
          ...(key ? { 'Idempotency-Key': key } : {}),
        },
        body: body ? JSON.stringify(body) : undefined,
      });
    } catch {
      await sleep(2 ** attempt * 1000); // network failure: retry with the same key
      continue;
    }

    if (response.ok) return response.json();

    const { error } = await response.json();
    const inUse = response.status === 409 && error.code === 'idempotency_key_in_use';
    if (!RETRYABLE.has(response.status) && !inUse) {
      // An error that will not go away on its own: log it and show it to whoever must fix it.
      throw Object.assign(new Error(error.message), { code: error.code, details: error.details, requestId: error.request_id });
    }

    const retryAfter = Number(response.headers.get('Retry-After'));
    await sleep(retryAfter > 0 ? retryAfter * 1000 : 2 ** attempt * 1000);
  }

  throw new Error('The CartaFlow API did not answer after 5 attempts.');
}

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