Add request timeouts and circuit breaker to payouts job

.gitignore
README.md
package.json
src/clients/payments.js
src/jobs/nightly-payouts.js
src/retry.js
test/payouts.test.js
{
  "name": "payouts-worker",
  "version": "2.1.0",
  "private": true,
  "type": "module",
  "scripts": {
    "payouts": "node src/jobs/nightly-payouts.js",
    "test": "node --test"
  },
  "engines": {
    "node": ">=20"
  }
}

import { withRetry } from "../retry.js";

export class PaymentsApiError extends Error {
  constructor(status, body) {
    super(`payments API answered ${status}`);
    this.name = "PaymentsApiError";
    this.status = status;
    this.body = body;
  }
}

export function createPaymentsClient({ baseUrl = process.env.PAYMENTS_API_URL, apiKey = process.env.PAYMENTS_API_KEY } = {}) {
  async function call(method, path, body) {
    return withRetry(
      async () => {
        const response = await fetch(new URL(path, baseUrl), {
          method,
          headers: { authorization: `Bearer ${apiKey}`, "content-type": "application/json" },
          body: body === undefined ? undefined : JSON.stringify(body),
        });
        const text = await response.text();
        if (!response.ok) throw new PaymentsApiError(response.status, text);
        return text ? JSON.parse(text) : null;
      },
      { label: `${method} ${path}` }
    );
  }

  return {
    listSellers: () => call("GET", "/v1/sellers?status=active"),
    getBalance: (sellerId) => call("GET", `/v1/sellers/${sellerId}/balance`),
    createPayout: (sellerId, amount, currency, idempotencyKey) =>
      call("POST", `/v1/sellers/${sellerId}/payouts`, { amount, currency, idempotency_key: idempotencyKey }),
  };
}
import { createPaymentsClient } from "../clients/payments.js";

export async function runNightlyPayouts(client = createPaymentsClient(), today = new Date().toISOString().slice(0, 10)) {
  const summary = { paid: 0, skipped: 0, failed: [] };
  const { data: sellers } = await client.listSellers();
  for (const seller of sellers) {
    try {
      console.log(`fetching balance for ${seller.id}`);
      const balance = await client.getBalance(seller.id);
      if (balance.available < 100) {
        summary.skipped++;
        continue;
      }
      await client.createPayout(seller.id, balance.available, balance.currency, `payout-${seller.id}-${today}`);
      summary.paid++;
    } catch (error) {
      console.error(`payout for ${seller.id} failed: ${error.message}`);
      summary.failed.push(seller.id);
    }
  }
  console.log(`payouts done: ${summary.paid} paid, ${summary.skipped} skipped, ${summary.failed.length} failed`);
  return summary;
}

if (import.meta.url === `file://${process.argv[1]}`) {
  runNightlyPayouts().then((summary) => {
    process.exitCode = summary.failed.length > 0 ? 1 : 0;
  });
}
export async function withRetry(fn, { attempts = 3, baseDelayMs = 500, label = "request" } = {}) {
  let lastError;
  for (let attempt = 1; attempt <= attempts; attempt++) {
    try {
      return await fn();
    } catch (error) {
      lastError = error;
      if (!isRetryable(error) || attempt === attempts) break;
      const delay = baseDelayMs * 2 ** (attempt - 1);
      console.warn(`${label} failed (${error.message}), retry ${attempt}/${attempts - 1} in ${delay}ms`);
      await new Promise((resolve) => setTimeout(resolve, delay));
    }
  }
  throw lastError;
}

function isRetryable(error) {
  if (error.status) return error.status === 429 || error.status >= 500;
  return error.name === "TypeError"; // fetch's network errors
}
import { test, after } from "node:test";
import assert from "node:assert/strict";
import http from "node:http";
import { createPaymentsClient } from "../src/clients/payments.js";
import { runNightlyPayouts } from "../src/jobs/nightly-payouts.js";

const payouts = [];
let balanceFailuresLeft = 0;

const server = http.createServer(async (req, res) => {
  const chunks = [];
  for await (const chunk of req) chunks.push(chunk);
  const json = (status, body) => {
    res.writeHead(status, { "content-type": "application/json" });
    res.end(JSON.stringify(body));
  };
  if (req.url === "/v1/sellers?status=active") return json(200, { data: [{ id: "sel_a" }, { id: "sel_b" }, { id: "sel_c" }] });
  const balance = req.url.match(/^\/v1\/sellers\/(\w+)\/balance$/);
  if (balance) {
    if (balanceFailuresLeft > 0) {
      balanceFailuresLeft--;
 …[shortened]