directus/api/src/middleware/cache.test.ts

import express from 'express';
import request from 'supertest';
import checkCacheMiddleware from './cache';

jest.mock('../cache');
jest.mock('../env', () => ({
	CACHE_ENABLED: true,
	CACHE_NAMESPACE: 'test',
	CACHE_STORE: 'memory',
	CACHE_TTL: '5s',
	CACHE_CONTROL_S_MAXAGE: true,
}));

const { cache } = jest.requireMock('../cache');
const env = jest.requireMock('../env');

const handler = jest.fn((req, res) => res.json({ data: 'Uncached value' }));
const setup = () => express().use(checkCacheMiddleware).all('/items/test', handler);

beforeEach(jest.clearAllMocks);

describe('cache middleware', () => {
	test('should return the cached response for a request', async () => {
		cache.get.mockResolvedValueOnce({ data: 'Cached value' });
		cache.get.mockResolvedValueOnce(new Date().getTime() + 1000 * 60);

		const res = await request(setup()).get('/items/test').send();

		expect(res.body.data).toBe('Cached value');
		expect(res.headers['vary']).toBe('Origin, Cache-Control');
		expect(res.headers['cache-control']).toMatch(/public, max-age=\d+, s-maxage=\d+/);
		expect(handler).not.toHaveBeenCalled();
	});

	test('should call the handler when there is no cached value', async () => {
		cache.get.mockResolvedValueOnce(undefined);

		const res = await request(setup()).get('/items/test').send();

		expect(res.body.data).toBe('Uncached value');
		expect(cache.get).toHaveBeenCalledTimes(1);
		expect(handler).toHaveBeenCalledTimes(1);
	});

	test('should not cache requests then the cache is disabled', async () => {
		env.CACHE_ENABLED = false;

		const res = await request(setup()).get('/items/test').send();

		expect(res.body.data).toBe('Uncached value');
		expect(cache.get).not.toHaveBeenCalled();
		expect(handler).toHaveBeenCalledTimes(1);

		env.CACHE_ENABLED = true;
	});

	test('should not use cache when the "Cache-Control" header is set to "no-store"', async () => {
		const res = await request(setup()).get('/items/test').set('Cache-Control', 'no-store').send();

		expect(res.body.data).toBe('Uncached value');
		expect(cache.get).not.toHaveBeenCalled();
		expect(handler).toHaveBeenCalledTimes(1);
	});

	test('should only cache get requests', async () => {
		const app = setup();

		await request(app).post('/items/test').send();
		await request(app).put('/items/test').send();
		await request(app).patch('/items/test').send();
		await request(app).delete('/items/test').send();

		expect(cache.get).not.toHaveBeenCalled();
		expect(handler).toHaveBeenCalledTimes(4);
	});
});