Step 10: 데이터 분석 및 통계 시스템 구현

주요 기능:
- Statistics Service 마이크로서비스 구축
- 실시간 메트릭 수집 시스템 (Kafka 연동)
- 시계열 데이터베이스 인터페이스 구현
- 데이터 집계 및 분석 엔진
- 사용자/시스템/이벤트 분석 API
- WebSocket 기반 실시간 대시보드
- 알림 규칙 및 임계값 설정
- CSV 데이터 내보내기

구현된 컴포넌트:
- MetricsCollector: Kafka 이벤트 메트릭 수집
- DataAggregator: 시간별/일별 데이터 집계
- TimeSeriesDB: 시계열 데이터 저장 인터페이스
- WebSocketManager: 실시간 데이터 스트리밍
- Analytics APIs: 다양한 분석 엔드포인트

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

services/statistics/backend/time_series_db.py

@@ -0,0 +1,165 @@
+"""
+Time Series Database Interface (Simplified for InfluxDB)
+"""
+import logging
+from typing import List, Dict, Any, Optional
+from datetime import datetime
+from models import Metric, AggregatedMetric
+
+logger = logging.getLogger(__name__)
+
+class TimeSeriesDB:
+    """Time series database interface"""
+    
+    def __init__(self, host: str, port: int, database: str):
+        self.host = host
+        self.port = port
+        self.database = database
+        self.is_connected = False
+        # In production, would use actual InfluxDB client
+        self.data_store = []  # Simplified in-memory storage
+        
+    async def connect(self):
+        """Connect to database"""
+        # Simplified connection
+        self.is_connected = True
+        logger.info(f"Connected to time series database at {self.host}:{self.port}")
+    
+    async def close(self):
+        """Close database connection"""
+        self.is_connected = False
+        logger.info("Disconnected from time series database")
+    
+    async def write_metrics(self, metrics: List[Metric]):
+        """Write metrics to database"""
+        for metric in metrics:
+            self.data_store.append({
+                "name": metric.name,
+                "value": metric.value,
+                "timestamp": metric.timestamp,
+                "tags": metric.tags,
+                "service": metric.service
+            })
+    
+    async def query_metrics(
+        self,
+        metric_type: str,
+        start_time: datetime,
+        end_time: datetime
+    ) -> List[Dict[str, Any]]:
+        """Query metrics from database"""
+        results = []
+        for data in self.data_store:
+            if (data["name"].startswith(metric_type) and
+                start_time <= data["timestamp"] <= end_time):
+                results.append(data)
+        return results
+    
+    async def get_time_series(
+        self,
+        metric_name: str,
+        start_time: datetime,
+        end_time: datetime,
+        interval: str
+    ) -> List[Dict[str, Any]]:
+        """Get time series data"""
+        return await self.query_metrics(metric_name, start_time, end_time)
+    
+    async def store_aggregated_metric(self, metric: AggregatedMetric):
+        """Store aggregated metric"""
+        self.data_store.append({
+            "name": f"agg.{metric.metric_name}",
+            "value": metric.value,
+            "timestamp": metric.end_time,
+            "tags": {"aggregation": metric.aggregation_type},
+            "service": "statistics"
+        })
+    
+    async def count_metrics(
+        self,
+        metric_type: str,
+        start_time: datetime,
+        end_time: datetime
+    ) -> int:
+        """Count metrics"""
+        metrics = await self.query_metrics(metric_type, start_time, end_time)
+        return len(metrics)
+    
+    async def get_average(
+        self,
+        metric_name: str,
+        start_time: datetime,
+        end_time: datetime
+    ) -> Optional[float]:
+        """Get average value"""
+        metrics = await self.query_metrics(metric_name, start_time, end_time)
+        if not metrics:
+            return None
+        values = [m["value"] for m in metrics]
+        return sum(values) / len(values)
+    
+    async def count_distinct_tags(
+        self,
+        metric_type: str,
+        tag_name: str,
+        start_time: datetime,
+        end_time: datetime
+    ) -> int:
+        """Count distinct tag values"""
+        metrics = await self.query_metrics(metric_type, start_time, end_time)
+        unique_values = set()
+        for metric in metrics:
+            if tag_name in metric.get("tags", {}):
+                unique_values.add(metric["tags"][tag_name])
+        return len(unique_values)
+    
+    async def get_top_metrics(
+        self,
+        metric_type: str,
+        group_by: str,
+        start_time: datetime,
+        end_time: datetime,
+        limit: int = 10
+    ) -> List[Dict[str, Any]]:
+        """Get top metrics grouped by tag"""
+        metrics = await self.query_metrics(metric_type, start_time, end_time)
+        grouped = {}
+        for metric in metrics:
+            key = metric.get("tags", {}).get(group_by, "unknown")
+            grouped[key] = grouped.get(key, 0) + 1
+        
+        sorted_items = sorted(grouped.items(), key=lambda x: x[1], reverse=True)
+        return [{"name": k, "count": v} for k, v in sorted_items[:limit]]
+    
+    async def count_metrics_with_value(
+        self,
+        metric_name: str,
+        value: float,
+        start_time: datetime,
+        end_time: datetime
+    ) -> int:
+        """Count metrics with specific value"""
+        metrics = await self.query_metrics(metric_name, start_time, end_time)
+        return sum(1 for m in metrics if m["value"] == value)
+    
+    async def get_metric_distribution(
+        self,
+        metric_type: str,
+        tag_name: str,
+        start_time: datetime,
+        end_time: datetime
+    ) -> Dict[str, int]:
+        """Get metric distribution by tag"""
+        metrics = await self.query_metrics(metric_type, start_time, end_time)
+        distribution = {}
+        for metric in metrics:
+            key = metric.get("tags", {}).get(tag_name, "unknown")
+            distribution[key] = distribution.get(key, 0) + 1
+        return distribution
+    
+    async def delete_old_data(self, cutoff_date: datetime):
+        """Delete old data"""
+        self.data_store = [
+            d for d in self.data_store
+            if d["timestamp"] >= cutoff_date
+        ]