refactor(core): Clean up Prometheus service (no-changelog) (#10068)

packages/cli/test/integration/prometheus-metrics.test.ts

@@ -0,0 +1,149 @@
+import { Container } from 'typedi';
+import { parse as semverParse } from 'semver';
+import request, { type Response } from 'supertest';
+
+import config from '@/config';
+import { N8N_VERSION } from '@/constants';
+import { PrometheusMetricsService } from '@/metrics/prometheus-metrics.service';
+import { setupTestServer } from './shared/utils';
+
+jest.unmock('@/eventbus/MessageEventBus/MessageEventBus');
+
+const toLines = (response: Response) => response.text.trim().split('\n');
+
+config.set('endpoints.metrics.enable', true);
+config.set('endpoints.metrics.prefix', 'n8n_test_');
+
+const server = setupTestServer({ endpointGroups: ['metrics'] });
+const agent = request.agent(server.app);
+
+let prometheusService: PrometheusMetricsService;
+
+describe('Metrics', () => {
+	beforeAll(() => {
+		prometheusService = Container.get(PrometheusMetricsService);
+	});
+
+	beforeEach(() => {
+		prometheusService.disableAllMetrics();
+	});
+
+	it('should return n8n version', async () => {
+		/**
+		 * Arrange
+		 */
+		await prometheusService.init(server.app);
+
+		/**
+		 * Act
+		 */
+		const response = await agent.get('/metrics');
+
+		/**
+		 * Assert
+		 */
+		expect(response.status).toEqual(200);
+		expect(response.type).toEqual('text/plain');
+
+		const n8nVersion = semverParse(N8N_VERSION);
+
+		if (!n8nVersion) fail('Failed to parse n8n version');
+
+		const { version, major, minor, patch } = n8nVersion;
+
+		expect(toLines(response)).toContain(
+			`n8n_test_version_info{version="v${version}",major="${major}",minor="${minor}",patch="${patch}"} 1`,
+		);
+	});
+
+	it('should return default metrics if enabled', async () => {
+		/**
+		 * Arrange
+		 */
+		prometheusService.enableMetric('default');
+		await prometheusService.init(server.app);
+
+		/**
+		 * Act
+		 */
+		const response = await agent.get('/metrics');
+
+		/**
+		 * Assert
+		 */
+		expect(response.status).toEqual(200);
+		expect(response.type).toEqual('text/plain');
+		expect(toLines(response)).toContain('nodejs_heap_space_size_total_bytes{space="read_only"} 0');
+	});
+
+	it('should not return default metrics if disabled', async () => {
+		/**
+		 * Arrange
+		 */
+		prometheusService.disableMetric('default');
+		await prometheusService.init(server.app);
+
+		/**
+		 * Act
+		 */
+		const response = await agent.get('/metrics');
+
+		/**
+		 * Assert
+		 */
+		expect(response.status).toEqual(200);
+		expect(response.type).toEqual('text/plain');
+		expect(toLines(response)).not.toContain(
+			'nodejs_heap_space_size_total_bytes{space="read_only"} 0',
+		);
+	});
+
+	it('should return cache metrics if enabled', async () => {
+		/**
+		 * Arrange
+		 */
+		prometheusService.enableMetric('cache');
+		await prometheusService.init(server.app);
+
+		/**
+		 * Act
+		 */
+		const response = await agent.get('/metrics');
+
+		/**
+		 * Assert
+		 */
+		expect(response.status).toEqual(200);
+		expect(response.type).toEqual('text/plain');
+
+		const lines = toLines(response);
+
+		expect(lines).toContain('n8n_test_cache_hits_total 0');
+		expect(lines).toContain('n8n_test_cache_misses_total 0');
+		expect(lines).toContain('n8n_test_cache_updates_total 0');
+	});
+
+	it('should not return cache metrics if disabled', async () => {
+		/**
+		 * Arrange
+		 */
+		await prometheusService.init(server.app);
+
+		/**
+		 * Act
+		 */
+		const response = await agent.get('/metrics');
+
+		/**
+		 * Assert
+		 */
+		expect(response.status).toEqual(200);
+		expect(response.type).toEqual('text/plain');
+
+		const lines = toLines(response);
+
+		expect(lines).not.toContain('n8n_test_cache_hits_total 0');
+		expect(lines).not.toContain('n8n_test_cache_misses_total 0');
+		expect(lines).not.toContain('n8n_test_cache_updates_total 0');
+	});
+});