node-zstandard

Node.js interface to Zstandard (zstd)

Includes Zstd 1.0.0 version for Linux (x86-64, glibc >=2.19), Windows (32 and 64 bits), and Mac OS X (Darwin).

Interface

var zstd = require ('node-zstandard')

$3

#### zstd.compress (inputFile, outputFile [, compLevel], callback)
#### zstd.compressFileToFile (inputFile, outputFile [, compLevel], callback)

* inputFile: Path to the to file to be compressed.
* outputFile: Path to store the resulting compressed file.
* compLevel: Compression level (default=3).
* callback: Function to be executed on task completion. Follows Node.js (err, result) pattern, being result equal to outputFile when succedded.

NOTE: Input and output files should be different. Output file is overwritten if it exists.

``
zstd.compress('./test', './test.zst', 3, (err, result) => {
if (err)
throw err;
console.log (result);
});
`

#### compressStreamToFile (readableStream, outputFile [, compLevel], callback)

* readableStream: Data Node.js Stream to be compressed.
* outputFile: Path to store the resulting compressed file.
* compLevel: Compression level (default=3).
* callback: Function to be executed on task initialization. Follows Node.js (err, result) pattern, being result an EventEmitter that can emit the following events:
* error: Emitted when an error reading the stream or creating the compressed file occurred. Error message is provided.
* end: Emitted when task ended successfully.

NOTE: Output file is overwritten if it exists.

`
zstd.compressStreamToFile(aReadableStream, './test.zst', 3, (err, result) => {
if (err)
throw err;
result.on('error', (err) => {
throw err;
}
result.on('end', () => {
console.log ('Compression ended');
}
console.log ('Compression started');
});
`

$3

#### zstd.decompress (inputFile, outputFile, callback)
#### zstd.decompressFileToFile (inputFile, outputFile, callback)

* inputFile: Path to the to compressed input file.
* outputFile: Path to store the resulting decompressed file.
* callback: Function to be executed on task completion. Follows Node.js (err, result) pattern, being result equal to outputFile when succedded.

NOTE: Input and output files should be different. Output file is overwritten if it exists.

`
zstd.decompress('./test.zst','./test', (err, result) => {
if (err)
throw err;
console.log (result);
});
`

#### decompressFileToStream (inputFile, writableStream, callback)

* inputFile: Path to the to compressed input file.
* writableStream: Node.js Stream where to output decompressed data.
* callback: Function to be executed on task initialization. Follows Node.js (err, result) pattern, being result an EventEmitter that can emit the following events:
* error: Emitted when an error involving streams or file decompression occurred. Error message is provided.
* finish: Emitted when finished writting decompressed data to output stream.

`
zstd.decompressFileToStream ('./test', aWritableStream, (err, result) => {
if (err)
throw err;
result.on('error', (err) => {
throw err;
}
result.on('finish', () => {
console.log ('Decompression finished');
}
console.log ('Decompression started');
});
`

#### decompressionStreamFromFile (inputFile, callback)

* inputFile: Path to the to compressed input file.
* callback: Function to be executed on task initialization. Follows Node.js (err, result) pattern, being result an EventEmitter that can emit the following events:
* error: Emitted when an error involving streams or file decompression occurred. Error message is provided.
* data: Emitted when a chunk of decompressed data is generated. Data is obviously provided.
* end: Emitted when decompression ended and all data events have been emitted.

`
zstd.decompressionStreamFromFile ('./test', (err, result) => {
if (err)
throw err;
var decompressedData = '';
result.on('error', (err) => {
throw err;
}
result.on('data', (data) => {
decompressedData += data;
}
result.on('end', () => {
console.log (decompressedData);
}
});
``

License

Apache 2.0