Metrics Endpoint

src/monitoring/metrics/metrics-collection.service.ts

@@ -1,12 +1,19 @@
 import { Injectable, OnModuleInit } from '@nestjs/common';
-import { Registry, collectDefaultMetrics, Histogram, Gauge } from 'prom-client';
+import { Registry, collectDefaultMetrics, Histogram, Gauge, Counter } from 'prom-client';
 
 @Injectable()
 export class MetricsCollectionService implements OnModuleInit {
   private registry: Registry;
   public httpRequestDuration: Histogram;
   public dbQueryDuration: Histogram;
   public activeConnections: Gauge;
+  public userRegistrations: Counter;
+  public assessmentCompletions: Counter;
+  public learningPathProgress: Gauge;
+  public cacheHitRate: Gauge;
+  public queueProcessingTime: Histogram;
+  public emailCampaignsSent: Counter;
+  public backupOperations: Counter;
 
   constructor() {
     this.registry = new Registry();
@@ -35,6 +42,63 @@ export class MetricsCollectionService implements OnModuleInit {
       help: 'Number of active connections',
       registers: [this.registry],
     });
+
+    // User Registrations Counter
+    this.userRegistrations = new Counter({
+      name: 'user_registrations_total',
+      help: 'Total number of user registrations',
+      labelNames: ['user_type', 'source'],
+      registers: [this.registry],
+    });
+
+    // Assessment Completions Counter
+    this.assessmentCompletions = new Counter({
+      name: 'assessment_completions_total',
+      help: 'Total number of assessment completions',
+      labelNames: ['assessment_type', 'difficulty'],
+      registers: [this.registry],
+    });
+
+    // Learning Path Progress Gauge
+    this.learningPathProgress = new Gauge({
+      name: 'learning_path_progress_percentage',
+      help: 'Average learning path progress percentage',
+      labelNames: ['path_id', 'user_id'],
+      registers: [this.registry],
+    });
+
+    // Cache Hit Rate Gauge
+    this.cacheHitRate = new Gauge({
+      name: 'cache_hit_rate_percentage',
+      help: 'Cache hit rate percentage',
+      labelNames: ['cache_type'],
+      registers: [this.registry],
+    });
+
+    // Queue Processing Time Histogram
+    this.queueProcessingTime = new Histogram({
+      name: 'queue_processing_duration_seconds',
+      help: 'Duration of queue job processing in seconds',
+      labelNames: ['queue_name', 'job_type'],
+      buckets: [0.1, 0.5, 1, 2, 5, 10, 30],
+      registers: [this.registry],
+    });
+
+    // Email Campaigns Sent Counter
+    this.emailCampaignsSent = new Counter({
+      name: 'email_campaigns_sent_total',
+      help: 'Total number of email campaigns sent',
+      labelNames: ['campaign_type', 'status'],
+      registers: [this.registry],
+    });
+
+    // Backup Operations Counter
+    this.backupOperations = new Counter({
+      name: 'backup_operations_total',
+      help: 'Total number of backup operations',
+      labelNames: ['operation_type', 'status'],
+      registers: [this.registry],
+    });
   }
 
   onModuleInit() {
@@ -57,4 +121,33 @@ export class MetricsCollectionService implements OnModuleInit {
   recordDbQuery(queryType: string, table: string, duration: number) {
     this.dbQueryDuration.observe({ query_type: queryType, table }, duration);
   }
+
+  // Custom business metrics methods
+  recordUserRegistration(userType: string, source: string) {
+    this.userRegistrations.inc({ user_type: userType, source });
+  }
+
+  recordAssessmentCompletion(assessmentType: string, difficulty: string) {
+    this.assessmentCompletions.inc({ assessment_type: assessmentType, difficulty });
+  }
+
+  updateLearningPathProgress(pathId: string, userId: string, progress: number) {
+    this.learningPathProgress.set({ path_id: pathId, user_id: userId }, progress);
+  }
+
+  updateCacheHitRate(cacheType: string, hitRate: number) {
+    this.cacheHitRate.set({ cache_type: cacheType }, hitRate);
+  }
+
+  recordQueueProcessingTime(queueName: string, jobType: string, duration: number) {
+    this.queueProcessingTime.observe({ queue_name: queueName, job_type: jobType }, duration);
+  }
+
+  recordEmailCampaignSent(campaignType: string, status: string) {
+    this.emailCampaignsSent.inc({ campaign_type: campaignType, status });
+  }
+
+  recordBackupOperation(operationType: string, status: string) {
+    this.backupOperations.inc({ operation_type: operationType, status });
+  }
 }

src/monitoring/monitoring.controller.ts

@@ -1,4 +1,5 @@
+import { Controller, Get, Res, Query } from '@nestjs/common';
 import { Controller, Get, Res, VERSION_NEUTRAL, Version } from '@nestjs/common';
 import { MetricsCollectionService } from './metrics/metrics-collection.service';
 import { Response } from 'express';
 import { ScheduledTaskMonitoringService } from './scheduled-task-monitoring.service';
@@ -9,7 +10,7 @@
   constructor(
     private readonly metricsService: MetricsCollectionService,
     private readonly scheduledTaskMonitoringService: ScheduledTaskMonitoringService,
-  ) {}
+  ) { }
 
   @Get()
   async getMetrics(@Res() res: Response) {
@@ -18,6 +19,105 @@
     res.send(metrics);
   }
 
+  @Get('unified')
+  async getUnifiedMetrics(
+    @Query('format') format?: string,
+    @Query('include') include?: string,
+    @Query('exclude') exclude?: string,
+  ) {
+    const includeTypes = include?.split(',').map(s => s.trim()) || [];
+    const excludeTypes = exclude?.split(',').map(s => s.trim()) || [];
+
+    // Get base Prometheus metrics
+    const prometheusMetrics = await this.metricsService.getMetrics();
+
+    // Get scheduled tasks dashboard
+    const scheduledTasksMetrics = this.scheduledTaskMonitoringService.getDashboard();
+
+    // Aggregate metrics from different sources
+    const unifiedMetrics = {
+      prometheus: prometheusMetrics,
+      scheduledTasks: scheduledTasksMetrics,
+      timestamp: new Date().toISOString(),
+      metadata: {
+        totalMetrics: prometheusMetrics.split('\n').filter(line => line && !line.startsWith('#')).length,
+        includeTypes,
+        excludeTypes,
+      }
+    };
+
+    // Return in requested format
+    if (format === 'json') {
+      return unifiedMetrics;
+    }
+
+    // Default to Prometheus format
+    const metrics = await this.metricsService.getMetrics();
+    return metrics;
+  }
+
+  @Get('health')
+  async getMetricsHealth() {
+    return {
+      status: 'healthy',
+      timestamp: new Date().toISOString(),
+      services: {
+        metricsCollection: 'active',
+        scheduledTasks: 'active',
+      },
+      registry: {
+        metricsCount: (await this.metricsService.getMetrics()).split('\n').filter(line => line && !line.startsWith('#')).length,
+      }
+    };
+  }
+
+  @Get('custom')
+  async getCustomMetrics(@Query('type') type?: string) {
+    const customMetrics = {
+      user_registrations: {
+        name: 'user_registrations_total',
+        help: 'Total number of user registrations',
+        type: 'counter',
+      },
+      assessment_completions: {
+        name: 'assessment_completions_total',
+        help: 'Total number of assessment completions',
+        type: 'counter',
+      },
+      learning_path_progress: {
+        name: 'learning_path_progress_percentage',
+        help: 'Average learning path progress percentage',
+        type: 'gauge',
+      },
+      cache_hit_rate: {
+        name: 'cache_hit_rate_percentage',
+        help: 'Cache hit rate percentage',
+        type: 'gauge',
+      },
+      queue_processing_time: {
+        name: 'queue_processing_duration_seconds',
+        help: 'Duration of queue job processing in seconds',
+        type: 'histogram',
+      },
+      email_campaigns_sent: {
+        name: 'email_campaigns_sent_total',
+        help: 'Total number of email campaigns sent',
+        type: 'counter',
+      },
+      backup_operations: {
+        name: 'backup_operations_total',
+        help: 'Total number of backup operations',
+        type: 'counter',
+      },
+    };
+
+    if (type) {
+      return customMetrics[type] || { error: 'Metric type not found' };
+    }
+
+    return customMetrics;
+  }
+
   @Get('scheduled-tasks/dashboard')
   getScheduledTasksDashboard() {
     return this.scheduledTaskMonitoringService.getDashboard();