AK-21/Graphite-Industrial-Intelligence

1'use strict';2 3// We define these manually to ensure they're always copied4// even if they would move up the prototype chain5// https://nodejs.org/api/http.html#http_class_http_incomingmessage6const knownProperties = [7	'aborted',8	'complete',9	'headers',10	'httpVersion',11	'httpVersionMinor',12	'httpVersionMajor',13	'method',14	'rawHeaders',15	'rawTrailers',16	'setTimeout',17	'socket',18	'statusCode',19	'statusMessage',20	'trailers',21	'url'22];23 24module.exports = (fromStream, toStream) => {25	if (toStream._readableState.autoDestroy) {26		throw new Error('The second stream must have the `autoDestroy` option set to `false`');27	}28 29	const fromProperties = new Set(Object.keys(fromStream).concat(knownProperties));30 31	const properties = {};32 33	for (const property of fromProperties) {34		// Don't overwrite existing properties.35		if (property in toStream) {36			continue;37		}38 39		properties[property] = {40			get() {41				const value = fromStream[property];42				const isFunction = typeof value === 'function';43 44				return isFunction ? value.bind(fromStream) : value;45			},46			set(value) {47				fromStream[property] = value;48			},49			enumerable: true,50			configurable: false51		};52	}53 54	Object.defineProperties(toStream, properties);55 56	fromStream.once('aborted', () => {57		toStream.destroy();58 59		toStream.emit('aborted');60	});61 62	fromStream.once('close', () => {63		if (fromStream.complete) {64			if (toStream.readable) {65				toStream.once('end', () => {66					toStream.emit('close');67				});68			} else {69				toStream.emit('close');70			}71		} else {72			toStream.emit('close');73		}74	});75 76	return toStream;77};78