implementing Singleton Pattern Implementation in Node.js - Unexpected Instantiation Issues
I can't seem to get This might be a silly question, but I'm prototyping a solution and I've hit a wall trying to I'm trying to configure I've been banging my head against this for hours. I'm trying to implement the Singleton design pattern in my Node.js application (v14.17.0), but I'm running into unexpected behavior where multiple instances of my class are being created. The goal is to restrict the instantiation of the class to a single object. Here's the code I've written so far: ```javascript class Database { constructor() { if (Database.instance) { return Database.instance; } this.connection = this.connect(); // Simulate a database connection Database.instance = this; } connect() { console.log('Database connected'); return {}; // Simulated connection object } } const db1 = new Database(); const db2 = new Database(); console.log(db1 === db2); // Expected to be true ``` To my surprise, the log statement prints `false`, indicating that `db1` and `db2` are different instances. I have tried moving the `Database.instance` assignment to various places within the constructor, but it hasn’t resolved the scenario. I also made sure that I’m not accidentally exporting multiple instances in my module. I’m using ES6 modules and exporting the instance like this: ```javascript module.exports = new Database(); ``` However, I still end up with two separate instances. Any insights on what might be causing this behavior? Furthermore, is there a more efficient way to enforce a singleton pattern in Node.js, especially when dealing with async operations or promises? I appreciate any help! For context: I'm using Javascript on macOS. How would you solve this? Thanks for your help in advance! My development environment is Debian. Thanks for taking the time to read this! I'm developing on Ubuntu 22.04 with Javascript. I'm open to any suggestions. I'm coming from a different tech stack and learning Javascript. Any advice would be much appreciated. For context: I'm using Javascript on CentOS. Has anyone else encountered this?