Here is a complete, easy-to-understand guide to the Node.js Zlib Module, with examples for compression and decompression.

🌟 Node.js Zlib Module

The zlib module in Node.js provides compression and decompression functionalities using popular algorithms like:

• Gzip

• Deflate

• Brotli (modern high-performance compression)

It is commonly used to:

✔ Compress files
✔ Decompress files
✔ Create zip-like buffers
✔ Stream compression (HTTP responses, file downloads)

✅ Import Zlib

🗜️ 1. Gzip Compression

Compress a string

result is a Buffer.

🔄 2. Gzip Decompression

📄 3. Compress a File using Streams

📂 4. Decompress a File using Streams

🌀 5. Deflate Compression

Compress:

Decompress:

⚡ 6. Brotli Compression (Modern & Better)

Brotli is better than gzip for text-based resources like HTML, CSS, JS.

Compress:

Decompress:

🔁 7. Stream-based Brotli Example

🔧 8. Custom Compression Options

🧠 9. Compression Levels

Levels range from 0 → 9

• 0 = no compression (fastest)

• 9 = maximum compression (slowest)

📌 10. Use Cases of Zlib

✔ Compressing files before upload/download
✔ Creating .gz compressed logs
✔ Sending compressed data over sockets
✔ Compressing HTTP responses (Content-Encoding: gzip)
✔ Faster web performance (Brotli for web servers)