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