有没有办法验证oracle SQL数据库连接和错误处理？

Question

最近我正在用

Oracle SQL Databse

配置

node.js

。
我能够成功建立数据库连接并能够执行查询。

我的数据库连接示例查询是：

import * as oracledb from 'oracledb';

export class OracleSQL {
    private static conn;

    static async connect() {
        this.conn: await oracledb.getConnection({
            connectString: "host:port/schema",
            user     :  "username",
            password :  "********"
        });
        // TODO: add some condition to verify database connected successfully
        // if (connection is established) {
            console.log('Database connected successfully');
            return true;
        // }
        
        // TODO: if connection not established for any reason and throwing error
        //       How to handle this error ? 
        //       is that a simple "Try...Catch" method or some other way ?
    }

    static async query(queryStr) {
        // TODO: add some condition to verify connection is still alive or not
        if (!this.conn) {
            let res = await this.connect()
            if (res) {
                return await this.conn.execute(queryStr);
            }
        } else {
            return await this.conn.execute(queryStr);
        }
    }

    static async close() {
        // TODO: add some condition to verify connection already established or not
        // if (connection is established) {
                await this.conn.close()
                .then(() => {
                    console.log('Database disconnected successfully');
                    this.conn = null;
                    return true;
                });
        // }
    }
}

我想在这里添加两个目标：

1. 如何检查我的连接是否已建立（活动）？
2. 如何处理错误？有数据库事件处理程序吗？

我查阅了 Node.js Oracle Connection、npm oracledb 文档。但没有找到任何有价值的信息。

---

经过大量研究后我发现，
Oracle DB 连接对象有一个属性

conn._impl.nscon.connected

，其中包含连接建立的布尔值。

import * as oracledb from 'oracledb';

const conn = await oracledb.getConnection({
                               connectString: "host:port/schema",
                               user     :  "username",
                               password :  "********"
                          });
if ( conn._impl.nscon.connected ) {
    console.log('Database connected successfully');
}

这是验证连接已建立或活动状态的有效方法吗？
我不知道。你有什么想法吗？

Answer 1

我建议使用

try/catch

方法来验证连接建立和错误处理

import * as oracledb from 'oracledb';

export class OracleSQL {
    private static conn;

    static async connect() {
        try{
            this.conn : await oracledb.getConnection({
                connectString: "host:port/schema",
                user     :  "username",
                password :  "********"
            });
            console.log('Database connected successfully');
            return true;
        }catch(e){
            console.log('Database connection failed, Reason:',e.message);
            return false;
        }
    }

    static async query(queryStr) {
        if (!this.conn) {
            let res = await this.connect()
            if (res) {
                return await this.conn.execute(queryStr);
            }
        } else {
            return await this.conn.execute(queryStr);
        }
    }

    static async close() {
        if (this.conn) {
                try{
                    await this.conn.close()
                    console.log('Database disconnected successfully');
                    this.conn = null;
                    return true;
                }catch(e){
                    console.log("Database disconnection failed, Reason", e.message);
                }
        }
    }
}