Integration tests

What a session covers

The tutor works through these with you, in conversation and code. A session ends when you have shown them, not when a video does.

1. Explain what an integration test exercises that a unit test cannot
2. Start the server against a test database and send a request
3. Spot the test that depends on data from an earlier test

In practice

A few lines that show Integration tests doing its job.

import { test, before, after } from "node:test";
import assert from "node:assert/strict";
import { build } from "../src/app.js";

let app;
before(async () => { app = await build({ databaseUrl: process.env.TEST_DATABASE_URL }); });
after(() => app.close());

test("creates an order", async () => {
  const res = await app.inject({ method: "POST", url: "/api/v1/orders",
    payload: { items: [{ sku: "A1", quantity: 2 }] } });
  assert.equal(res.statusCode, 201);
  assert.match(res.headers.location, /\/orders\//);
});

The common mistake

What to know first

Your roadmap puts these before Integration tests, unless you already know them.

• Unit tests
• Routing

How it stays learned

Once a session shows you understand Integration tests, it comes back for review. Each review takes a minute and tells the memory model how well you still know it.

1. Day 3First recall, while it is fresh
2. Day 7Second, a week on
3. Day 18Last, when it has settled

Where it leads

Topics that build on Integration tests.

• Test databases