重构后端，完善获取资源/下载列表、博客列表接口

Server/src/Plugs/MySQLConnection.ts

@@ -0,0 +1,77 @@
+// MYSQL数据库连接池
+// 版本：v0.1
+import mysql from "mysql2/promise";
+import Logger from "./Logger";
+import config from "../config";
+
+class MySQLConnectPool {
+    private pool: any;
+    private logger = new Logger('MySQLConnection');
+
+    constructor() {
+        this.pool = this.createConnectPool();
+        this.logger.info("[MySQL] 数据库连接池已创建")
+        setTimeout(async () => {
+            let res = await this.testConnection();
+            if (res)
+                this.logger.info("[MySQL] 数据库测试成功")
+            else
+                this.logger.error("[MySQL] 数据库测试失败")
+        }, 10);
+    }
+
+    // 内部函数，无需手动调用
+    createConnectPool() {
+        return mysql.createPool({
+            host: config.mysql.host,
+            database: config.mysql.database,
+            user: config.mysql.user,
+            password: config.mysql.password,
+            waitForConnections: true,
+            connectionLimit: 10,
+            queueLimit: 0
+        })
+    }
+
+    // 内部函数，无需手动调用
+    async testConnection() {
+        try {
+            let res = await this.execute("SELECT 1 + 1 As result");
+            if (res[0].result == 2)
+                return 1;
+            else
+                return 0;
+        } catch (error) {
+            this.logger.error(`[MySQL] 数据库测试发生了错误：` + error);
+            return 0;
+        }
+
+    }
+
+    // 执行SQL语句
+    async execute(sql: string, values?: any[], database?: string) {
+        let connection: any;
+        try {
+            connection = await this.pool.getConnection();
+
+            // 如果指定了数据库，则更改当前连接的数据库
+            if (database) {
+                await connection.changeUser({ database });
+            }
+
+            let [rows, fields] = await connection.execute(sql, values);
+            return rows;
+        } catch (error) {
+            this.logger.error("[MySQL] 数据库发生错误:" + error, '\n##', sql, '\n##', JSON.stringify(values));
+            return undefined;
+        } finally {
+            if (database)
+                await connection.changeUser({ database: config.mysql.database });// 恢复默认数据库
+            if (connection)
+                connection.release();
+        }
+    }
+}
+
+let MySQLConnection = new MySQLConnectPool();
+export default MySQLConnection;