feat(phase-5-3): 모니터링 강화

logger.ts, metrics.ts, /api/metrics 추가
Version: e3bcb4ae

src/routes/api.ts

@@ -6,6 +6,7 @@ import {
   generateAIResponse,
 } from '../summary-service';
 import { handleCommand } from '../commands';
+import { openaiCircuitBreaker } from '../openai-service';
 
 // 사용자 조회/생성
 async function getOrCreateUser(
@@ -59,6 +60,9 @@ async function getOrCreateUser(
  *      -H "Origin: https://hosting.anvil.it.com" \
  *      -H "Content-Type: application/json" \
  *      -d '{"email":"test@example.com","message":"test message"}'
+ * 6. Test metrics (Circuit Breaker status):
+ *    curl http://localhost:8787/api/metrics \
+ *      -H "Authorization: Bearer your-webhook-secret"
  */
 export async function handleApiRequest(request: Request, env: Env, url: URL): Promise<Response> {
   // Deposit API - 잔액 조회 (namecheap-api 전용)
@@ -314,5 +318,60 @@ export async function handleApiRequest(request: Request, env: Env, url: URL): Pr
     });
   }
 
+  // Metrics API - Circuit Breaker 상태 조회 (관리자 전용)
+  if (url.pathname === '/api/metrics' && request.method === 'GET') {
+    try {
+      // WEBHOOK_SECRET 인증
+      const authHeader = request.headers.get('Authorization');
+      if (!env.WEBHOOK_SECRET || authHeader !== `Bearer ${env.WEBHOOK_SECRET}`) {
+        return Response.json({ error: 'Unauthorized' }, { status: 401 });
+      }
+
+      // Circuit Breaker 상태 수집
+      const openaiStats = openaiCircuitBreaker.getStats();
+
+      // 메트릭 응답 생성
+      const metrics = {
+        timestamp: new Date().toISOString(),
+        circuitBreakers: {
+          openai: {
+            state: openaiStats.state,
+            failures: openaiStats.failures,
+            lastFailureTime: openaiStats.lastFailureTime?.toISOString(),
+            stats: openaiStats.stats,
+            config: openaiStats.config,
+          },
+        },
+        // 추후 확장 가능: API 호출 통계, 캐시 hit rate 등
+        metrics: {
+          api_calls: {
+            // 추후 구현: 실제 API 호출 통계
+            openai: { count: openaiStats.stats.totalRequests, avg_duration: 0 },
+          },
+          errors: {
+            // 추후 구현: 에러 통계
+            retry_exhausted: 0,
+            circuit_breaker_open: openaiStats.state === 'OPEN' ? 1 : 0,
+          },
+          cache: {
+            // 추후 구현: 캐시 hit rate
+            hit_rate: 0,
+          },
+        },
+      };
+
+      console.log('[Metrics API] Circuit breaker stats retrieved:', {
+        state: openaiStats.state,
+        failures: openaiStats.failures,
+        requests: openaiStats.stats.totalRequests,
+      });
+
+      return Response.json(metrics);
+    } catch (error) {
+      console.error('[Metrics API] Error:', error);
+      return Response.json({ error: String(error) }, { status: 500 });
+    }
+  }
+
   return new Response('Not Found', { status: 404 });
 }