crc32-stream

What is crc32-stream?

The crc32-stream npm package is designed for generating CRC32 checksums from streams of data. It is particularly useful for validating the integrity of data being transferred or stored. The package provides a way to compute CRC32 checksums efficiently on-the-fly for both streams of data and individual files.

What are crc32-stream's main functionalities?

CRC32 Checksum for Streams

This feature allows you to create a CRC32 checksum for data streams. The code sample demonstrates how to pipe a file stream through the CRC32Stream to compute its checksum.

const {CRC32Stream} = require('crc32-stream');
const fs = require('fs');

const source = fs.createReadStream('path/to/file');
const crc32Stream = new CRC32Stream();

source.pipe(crc32Stream).on('finish', function() {
  console.log('CRC32 Checksum:', crc32Stream.digest().toString(16));
});

CRC32 Checksum for Files

This feature demonstrates how to compute and append a CRC32 checksum for files. It shows the process of reading a file, computing the checksum as the file is being processed, and then writing the output to another file.

const {CRC32Stream} = require('crc32-stream');
const fs = require('fs');

const crc32Stream = new CRC32Stream();
const output = fs.createWriteStream('output.file');

fs.createReadStream('input.file')
  .pipe(crc32Stream)
  .pipe(output)
  .on('finish', function() {
    console.log('File processed with CRC32 Checksum:', crc32Stream.digest().toString(16));
  });

Other packages similar to crc32-stream

crc

The 'crc' package offers a collection of CRC (Cyclic Redundancy Check) algorithms for strings and buffers. Unlike crc32-stream, which is stream-focused, 'crc' provides a more general approach to CRC calculation, supporting various CRC algorithms but without native stream support.

hash-stream-validation

This package is designed to validate streams using various hash algorithms, including CRC32. It is similar to crc32-stream in its stream-oriented approach but offers more flexibility by supporting additional hash algorithms like MD5 and SHA-1.

README

CRC32 Stream

crc32-stream is a streaming CRC32 checksumer. It uses the crc module behind the scenes to reliably handle binary data and fancy character sets. Data is passed through untouched.

Install

npm install crc32-stream --save

You can also use npm install https://github.com/archiverjs/node-crc32-stream/archive/master.tar.gz to test upcoming versions.

Usage

CRC32Stream

Inherits Transform Stream options and methods.

const {CRC32Stream} = require('crc32-stream');

const source = fs.createReadStream('file.txt');
const checksum = new CRC32Stream();

checksum.on('end', function(err) {
  // do something with checksum.digest() here
});

// either pipe it
source.pipe(checksum);

// or write it
checksum.write('string');
checksum.end();

DeflateCRC32Stream

Inherits zlib.DeflateRaw options and methods.

const {DeflateCRC32Stream} = require('crc32-stream');

const source = fs.createReadStream('file.txt');
const checksum = new DeflateCRC32Stream();

checksum.on('end', function(err) {
  // do something with checksum.digest() here
});

// either pipe it
source.pipe(checksum);

// or write it
checksum.write('string');
checksum.end();

Instance API

digest()

Returns the checksum digest in unsigned form.

hex()

Returns the hexadecimal representation of the checksum digest. (ie E81722F0)

size(compressed)

Returns the raw size/length of passed-through data.

If compressed is true, it returns compressed length instead. (DeflateCRC32Stream)

Things of Interest

• Changelog
• Contributing
• MIT License