Node.js provides powerful global objects that can be used directly without importing any module. These objects help us interact with the system, files, and memory.
Important global objects in Node.js (__dirname, process, Buffer)
1. What are Global Objects?
Global objects are available everywhere in your Node.js application. You don’t need to import them using require().
2. __dirname
Returns the directory name of the current file.
console.log(__dirname);
Output:
C:\Users\YourFolder\node-project
Used for handling file paths.
3. __filename
Returns the full path of the current file.
console.log(__filename);
4. process Object
The process object provides information about the current Node.js process.
Check Node Version
console.log(process.version);
Current Working Directory
console.log(process.cwd());
Environment Variables
console.log(process.env);
5. Buffer
Buffer is used to handle binary data in Node.js.
- Reading files
- Handling streams
- Working with TCP servers
Example:
const buf = Buffer.from("Hello");
console.log(buf);
console.log(buf.toString());
Output:
<Buffer 48 65 6c 6c 6f>
Hello
Hello
6. Real-World Usage
- Creating dynamic file paths
- Accessing environment variables
- Handling file uploads
- Working with streams
7. Common Beginner Mistakes
- Trying to import global objects
- Using __dirname in browser
- Not converting Buffer to string
Global objects are available only in Node.js, not in the browser.
Conclusion
These global objects are used in almost every Node.js application.
Your Hero to Zero Node.js journey is getting deeper 💚🚀
Tags
NodeJS