修復 too many connection 問題

lib/database-monitor.ts

@@ -50,21 +50,25 @@ export class DatabaseMonitor {
 
   // 檢查連線狀態
   private async checkConnectionStatus() {
+    let connection = null;
     try {
+      // 使用單一連線來檢查狀態，避免建立多個連線
+      connection = await db.getConnection();
+      
       // 檢查當前連線數
-      const statusResult = await db.queryOne(`
+      const [statusResult] = await connection.execute(`
         SHOW STATUS LIKE 'Threads_connected'
       `);
       
-      const currentConnections = statusResult?.Value || 0;
+      const currentConnections = statusResult[0]?.Value || 0;
       this.connectionCount = parseInt(currentConnections);
 
       // 檢查最大連線數
-      const maxConnResult = await db.queryOne(`
+      const [maxConnResult] = await connection.execute(`
         SHOW VARIABLES LIKE 'max_connections'
       `);
       
-      this.maxConnections = parseInt(maxConnResult?.Value || '100');
+      this.maxConnections = parseInt(maxConnResult[0]?.Value || '100');
 
       // 檢查連線使用率
       const usagePercentage = (this.connectionCount / this.maxConnections) * 100;
@@ -80,43 +84,68 @@ export class DatabaseMonitor {
       }
 
       // 檢查長時間運行的查詢
-      await this.checkLongRunningQueries();
+      await this.checkLongRunningQueries(connection);
 
     } catch (error) {
       console.error('❌ 資料庫監控錯誤:', error);
+    } finally {
+      // 確保釋放連線
+      if (connection) {
+        try {
+          connection.release();
+        } catch (releaseError) {
+          console.error('❌ 釋放監控連線失敗:', releaseError);
+        }
+      }
     }
   }
 
   // 檢查長時間運行的查詢
-  private async checkLongRunningQueries() {
+  private async checkLongRunningQueries(connection?: any) {
     try {
-      const longQueries = await db.query(`
-        SELECT 
-          ID,
-          USER,
-          HOST,
-          DB,
-          COMMAND,
-          TIME,
-          STATE,
-          INFO
-        FROM information_schema.PROCESSLIST 
-        WHERE TIME > 30 
-        AND COMMAND != 'Sleep'
-        ORDER BY TIME DESC
-        LIMIT 5
-      `);
+      // 如果沒有傳入連線，則建立一個新的
+      let tempConnection = connection;
+      let shouldRelease = false;
+      
+      if (!tempConnection) {
+        tempConnection = await db.getConnection();
+        shouldRelease = true;
+      }
+      
+      try {
+        const [longQueries] = await tempConnection.execute(`
+          SELECT 
+            ID,
+            USER,
+            HOST,
+            DB,
+            COMMAND,
+            TIME,
+            STATE,
+            INFO
+          FROM information_schema.PROCESSLIST 
+          WHERE TIME > 30 
+          AND COMMAND != 'Sleep'
+          ORDER BY TIME DESC
+          LIMIT 5
+        `);
 
-      if (longQueries.length > 0) {
-        console.warn(`⚠️ 發現 ${longQueries.length} 個長時間運行的查詢:`);
-        longQueries.forEach((query, index) => {
-          console.warn(`  ${index + 1}. 用戶: ${query.USER}, 時間: ${query.TIME}s, 狀態: ${query.STATE}`);
-          if (query.INFO && query.INFO.length > 100) {
-            console.warn(`     查詢: ${query.INFO.substring(0, 100)}...`);
-          } else if (query.INFO) {
-            console.warn(`     查詢: ${query.INFO}`);
-          }
-        });
+        if (longQueries.length > 0) {
+          console.warn(`⚠️ 發現 ${longQueries.length} 個長時間運行的查詢:`);
+          longQueries.forEach((query: any, index: number) => {
+            console.warn(`  ${index + 1}. 用戶: ${query.USER}, 時間: ${query.TIME}s, 狀態: ${query.STATE}`);
+            if (query.INFO && query.INFO.length > 100) {
+              console.warn(`     查詢: ${query.INFO.substring(0, 100)}...`);
+            } else if (query.INFO) {
+              console.warn(`     查詢: ${query.INFO}`);
+            }
+          });
+        }
+      } finally {
+        // 只有當我們建立了新連線時才釋放
+        if (shouldRelease && tempConnection) {
+          tempConnection.release();
+        }
       }
     } catch (error) {
       console.error('❌ 檢查長時間查詢時發生錯誤:', error);