cryptozip.js

A lightweight Node.js utility for compressing and encrypting files or buffers — and for decompressing and decrypting them later.
It wraps Node’s native zlib and crypto modules to provide a simple async API for secure, stream-based ZIP operations.

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🚀 Features

• 🔒 AES-256-CBC encryption with password protection
• 🗜️ Gzip compression/decompression
• 💾 Works with buffers, strings, or files
• ⚙️ Stream-based design for efficiency
• 🧩 Promise-based (async/await friendly)

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📦 Installation

npm install cryptozip

(Or just copy cryptozip.js into your project if you prefer a standalone file.)

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🧠 Usage

Import

const { zip, unzip } = require('./cryptozip');

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🔐 Compress & Encrypt

Compress a string or file, optionally with a password.

Example 1 — In-memory compression with password

const { zip } = require('./cryptozip');

(async () => {
  const data = 'Hello Secure World!';
  const zipped = await zip(data, { password: 'mySecret123' });

  console.log('Compressed & encrypted buffer:', zipped);
})();

Example 2 — Compress a file and save to disk

await zip({ file: 'input.txt' }, { password: 'mypwd', outputFile: 'output.gzenc' });

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🔓 Decompress & Decrypt

Example 1 — In-memory decryption

const { unzip } = require('./cryptozip');

(async () => {
  const decrypted = await unzip(zipped, { password: 'mySecret123' });
  console.log(decrypted.toString());
})();

Example 2 — Decrypt file to disk

await unzip({ file: 'output.gzenc' }, { password: 'mypwd', outputFile: 'restored.txt' });

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⚙️ API Reference

zip(input, [options])

Parameter	Type	Description
input	string | Buffer | { file: string }	Input data or path to file to compress
options.password	string (optional)	Encrypt with AES-256-CBC using this password
options.outputFile	string (optional)	If set, write result to this file
Returns	Promise<Buffer | undefined>	Returns compressed buffer (if no outputFile) or writes to disk

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unzip(input, [options])

Parameter	Type	Description
input	Buffer | { file: string }	Input data or file path to decompress
options.password	string (optional)	Decrypt with AES-256-CBC using this password
options.outputFile	string (optional)	If set, write result to this file
Returns	Promise<Buffer | undefined>	Returns decompressed buffer or writes to disk

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🧩 Notes

• AES-256-CBC encryption is used, with a random IV stored at the start of the file/buffer.
• When outputFile is used, no buffer is returned — data is written directly to disk.
• The password must be the same for compression and decompression.

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🧪 Example CLI

You can quickly test it in Node REPL or add a simple CLI:

node -e "const {zip, unzip}=require('./cryptozip');(async()=>{await zip({file:'a.txt'},{password:'123',outputFile:'a.gzenc'})})();"

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📝 License

MIT © 2025