Send email from Bun with one API call.

# .env - Bun reads this file on its own; no dotenv package.
NOTIX_API_KEY=notix_your_key_here

import { Notix } from "notix-js";

// Bun.env is an alias for process.env; either works. The key comes from .env.
const notix = new Notix(Bun.env.NOTIX_API_KEY);

// Pointing at a different Notix base URL (a staging environment, say)?
// Pass it as the second argument.
// const notix = new Notix(Bun.env.NOTIX_API_KEY, "https://notix.example.com");

import { Notix } from "notix-js";

const notix = new Notix(Bun.env.NOTIX_API_KEY);

Bun.serve({
  port: 3000,
  routes: {
    // A POST from your checkout, your signup form, or a queue worker.
    "/api/receipts": {
      POST: async (request) => {
        const { orderId, to } = await request.json();

        const { data, error } = await notix.emails.send(
          {
            from: "receipts@acme.com",
            to,
            subject: `Your receipt for order ${orderId}`,
            html: `<p>Thanks for order ${orderId}.</p>`,
            text: `Thanks for order ${orderId}.`,
          },
          // A retried request with the same key returns the original send.
          { idempotencyKey: `order-${orderId}-receipt` },
        );

        if (error) {
          return Response.json({ error }, { status: 502 });
        }
        return Response.json({ id: data.emailId });
      },
    },
  },
  // Anything not matched above.
  fetch() {
    return new Response("Not found", { status: 404 });
  },
});

// bun run server.ts

import { describe, expect, mock, test } from "bun:test";

// Replace the SDK module before the code under test imports it. The factory
// runs lazily, when something imports "notix-js".
const send = mock(async () => ({ data: { emailId: "em_test" }, error: null }));
mock.module("notix-js", () => ({
  Notix: class {
    emails = { send };
  },
}));

const { sendReceipt } = await import("./receipts");

describe("sendReceipt", () => {
  test("sends one email with the order's idempotency key", async () => {
    const id = await sendReceipt({ orderId: "4471", to: "customer@example.com" });

    expect(id).toBe("em_test");
    expect(send).toHaveBeenCalledTimes(1);
    expect(send.mock.calls[0]?.[1]).toEqual({ idempotencyKey: "order-4471-receipt" });
  });
});

// bun test