name : ZlibHeaderTransformStream.js "use strict"; import stream from "stream"; class ZlibHeaderTransformStream extends stream.Transform { __transform(chunk, encoding, callback) { this.push(chunk); callback(); } _transform(chunk, encoding, callback) { if (chunk.length !== 0) { this._transform = this.__transform; // Add Default Compression headers if no zlib headers are present if (chunk[0] !== 120) { // Hex: 78 const header = Buffer.alloc(2); header[0] = 120; // Hex: 78 header[1] = 156; // Hex: 9C this.push(header, encoding); } } this.__transform(chunk, encoding, callback); } } export default ZlibHeaderTransformStream;