IBM/node-celery-ts

// BSD 3-Clause License
//
// Copyright (c) 2018, IBM Corporation
// All rights reserved.
//
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// modification, are permitted provided that the following conditions are met:
//
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//   list of conditions and the following disclaimer.
//
// * Redistributions in binary form must reproduce the above copyright notice,
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//   this software without specific prior written permission.
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import * as Zlib from "zlib";

/**
 * encapsulates compression of arbitrary binary data
 */
export interface Compressor {
    compress(buffer: Buffer): Buffer;

    decompress(buffer: Buffer): Buffer;
}

/**
 * @returns a Compressor that returns a copy of its inputs
 */
export const createIdentityCompressor = (): Compressor => ({
    compress: (buffer: Buffer) => Buffer.from(buffer),

    decompress: (buffer: Buffer) => Buffer.from(buffer),
});

/**
 * uses zlib.g{un,}zipSync
 *
 * @returns a Compressor that uses the GZip compression method
 */
export const createGzipCompressor = (): Compressor => ({
    compress: (buffer: Buffer) => Zlib.gzipSync(buffer),

    decompress: (buffer: Buffer) => Zlib.unzipSync(buffer),
});

/**
 * uses zlib.{de,in}flateSync
 *
 * @returns a Compressor that uses the Zlib compression method
 */
export const createZlibCompressor = (): Compressor => ({
    compress: (buffer: Buffer) => Zlib.deflateSync(buffer),

    decompress: (buffer: Buffer) => Zlib.unzipSync(buffer),
});