feat: use on application bootstrap lifecycle event

Author: netanelavr

README.md

@@ -43,7 +43,7 @@ ReporterService.counter('api_requests_total', { endpoint: '/users' });
 Unlike [@willsoto/nestjs-prometheus](https://github.com/willsoto/nestjs-prometheus), `nestjs-metrics-client` removes the need for cumbersome dependency injection, making your code cleaner and more portable.
 
 🌟 **Effortless Integration**  
-With minimal setup, you can start tracking metrics immediately. No need to configure a service in every file—just use the global `ReporterService`.
+With zero setup, you can start tracking metrics immediately. No need to configure a service in every file—just use the global `ReporterService`.
 
 🎯 **Focus on Simplicity**  
 Designed for developers who want powerful metrics without the complexity of managing dependencies or boilerplate code.
@@ -75,25 +75,7 @@ import { ReporterModule } from 'nestjs-metrics-client';
 export class AppModule {}
 ```
 
-### 2. Initialize the Global Reporter
-
-Easily initialize the global `ReporterService` in your bootstrap function. No additional injections required.
-
-```typescript
-import { NestFactory } from '@nestjs/core';
-import { MetricsService, ReporterService } from 'nestjs-metrics-client';
-
-async function bootstrap() {
-  const app = await NestFactory.create(AppModule);
-
-  // Initialize the global reporter
-  ReporterService.init(app.get(MetricsService));
-
-  await app.listen(3000);
-}
-```
-
-### 3. Report Metrics Anywhere
+### 2. Report Metrics Anywhere
 
 Once initialized, you can start reporting metrics instantly from anywhere in your application.
 
@@ -125,7 +107,6 @@ The global static service for reporting metrics:
 
 | Method       | Description                 | Parameters                                                  |
 |--------------|-----------------------------|-------------------------------------------------------------|
-| `init()`     | Initialize the reporter     | `metricsService: MetricsService`                           |
 | `counter()`  | Increment a counter metric  | `key: string, labels?: Record<string, string | number>`     |
 | `gauge()`    | Set a gauge value          | `key: string, value: number, labels?: Record<string, string | number>` |
 | `histogram()`| Record a histogram value    | `key: string, value: number, labels?: Record<string, string | number>, buckets?: number[]` |

src/reporter/reporter.service.ts

@@ -1,56 +1,41 @@
-import { Logger } from '@nestjs/common';
+import { Injectable, Logger, OnApplicationBootstrap } from '@nestjs/common';
 import { MetricsService } from '../metrics/metrics.service';
 
-export class ReporterService {
+@Injectable()
+export class ReporterService implements OnApplicationBootstrap {
 	private static readonly logger = new Logger( ReporterService.name );
 	private static metricsService: MetricsService;
 
-	static init( metricsService: MetricsService ): void {
-		ReporterService.metricsService = metricsService;
+	constructor( private readonly metrics: MetricsService ) {}
+	onApplicationBootstrap() {
+		ReporterService.metricsService = this.metrics;
 	}
 
-	static counter(
-		key: string,
-		labels?: Record<string, string | number>
-	): void {
+	static counter(key: string, labels?: Record<string, string | number>): void {
 		try {
 			ReporterService.metricsService.incCounter( key, labels );
 		} catch ( error ) {
 			this.logger.error( `Error while incrementing counter - ${ key }`, error );
 		}
 	}
 
-	static gauge(
-		key: string,
-		value: number,
-		labels?: Record<string, string | number>
-	): void {
+	static gauge(key: string, value: number, labels?: Record<string, string | number>): void {
 		try {
 			ReporterService.metricsService.setGauge( key, value, labels );
 		} catch ( error ) {
 			this.logger.error( `Error while setting gauge - ${ key }, ${ value }`, error );
 		}
 	}
 
-	static histogram(
-		key: string,
-		value: number,
-		labels?: Record<string, string | number>,
-		buckets?: number[]
-	): void {
+	static histogram(key: string, value: number, labels?: Record<string, string | number>, buckets?: number[]): void {
 		try {
 			ReporterService.metricsService.observeHistogram( key, value, labels, buckets );
 		} catch ( error ) {
 			this.logger.error( `Error while observing histogram - ${ key }, ${ value }`, error );
 		}
 	}
 
-	static summary(
-		key: string,
-		value: number,
-		labels?: Record<string, string | number>,
-		percentiles?: number[]
-	): void {
+	static summary(key: string, value: number, labels?: Record<string, string | number>, percentiles?: number[]): void {
 		try {
 			ReporterService.metricsService.observeSummary( key, value, labels, percentiles );
 		} catch ( error ) {

tests/reporter.module.spec.ts

@@ -9,6 +9,7 @@ describe('ReporterModule', () => {
 		if (module) {
 			await module.close();
 		}
+		(ReporterService as any).metricsService = undefined;
 	});
 
 	describe('forRoot', () => {
@@ -23,28 +24,29 @@ describe('ReporterModule', () => {
 					})
 				],
 			}).compile();
-               
-			const metricsService = module.get<MetricsService>(MetricsService);
-			ReporterService.init(metricsService);
+			
+			const reporterService = module.get<ReporterService>(ReporterService);
+			reporterService.onApplicationBootstrap();
+			
 			ReporterService.counter('test_counter');
 
 			const registry = module.get<Registry>(Registry);
 			const metrics = await registry.metrics();
-               
+			
 			expect(metrics).toContain('app="test-app"');
 			expect(metrics).toContain('environment="test"');
 		});
-          
+		
 		it('should work without configuration', async () => {
 			module = await Test.createTestingModule({
 				imports: [ReporterModule.forRoot()],
 			}).compile();
-               
+			
 			expect(module.get(Registry)).toBeDefined();
 			expect(module.get(MetricsService)).toBeDefined();
 		});
 	});
-     
+	
 	describe('forRootAsync', () => {
 		it('should support async configuration', async () => {
 			module = await Test.createTestingModule({
@@ -58,9 +60,10 @@ describe('ReporterModule', () => {
 					})
 				],
 			}).compile();
-               
-			const metricsService = module.get<MetricsService>(MetricsService);
-			ReporterService.init(metricsService);
+			
+			const reporterService = module.get<ReporterService>(ReporterService);
+			reporterService.onApplicationBootstrap();
+			
 			ReporterService.counter('test_counter');
 
 			const registry = module.get<Registry>(Registry);
@@ -98,4 +101,4 @@ describe('ReporterModule', () => {
 			}).compile()).rejects.toThrow('Config error');
 		});
 	});
-});
+});