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rOACCT/node_modules/http-proxy-middleware/dist/handlers/response-interceptor.js
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response-interceptor.js
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			"use strict";
			Object.defineProperty(exports, "__esModule", { value: true });
			exports.responseInterceptor = void 0;
			const zlib = require("zlib");
			/**
			* Intercept responses from upstream.
			* Automatically decompress (deflate, gzip, brotli).
			* Give developer the opportunity to modify intercepted Buffer and http.ServerResponse
			*
			* NOTE: must set options.selfHandleResponse=true (prevent automatic call of res.end())
			*/
			function responseInterceptor(interceptor) {
			return async function proxyRes(proxyRes, req, res) {
			const originalProxyRes = proxyRes;
			let buffer = Buffer.from('', 'utf8');
			// decompress proxy response
			const _proxyRes = decompress(proxyRes, proxyRes.headers['content-encoding']);
			// concat data stream
			_proxyRes.on('data', (chunk) => (buffer = Buffer.concat([buffer, chunk])));
			_proxyRes.on('end', async () => {
			// copy original headers
			copyHeaders(proxyRes, res);
			// call interceptor with intercepted response (buffer)
			const interceptedBuffer = Buffer.from(await interceptor(buffer, originalProxyRes, req, res));
			// set correct content-length (with double byte character support)
			res.setHeader('content-length', Buffer.byteLength(interceptedBuffer, 'utf8'));
			res.write(interceptedBuffer);
			res.end();
			});
			_proxyRes.on('error', (error) => {
			res.end(`Error fetching proxied request: ${error.message}`);
			});
			};
			}
			exports.responseInterceptor = responseInterceptor;
			/**
			* Streaming decompression of proxy response
			* source: https://github.com/apache/superset/blob/9773aba522e957ed9423045ca153219638a85d2f/superset-frontend/webpack.proxy-config.js#L116
			*/
			function decompress(proxyRes, contentEncoding) {
			let _proxyRes = proxyRes;
			let decompress;
			switch (contentEncoding) {
			case 'gzip':
			decompress = zlib.createGunzip();
			break;
			case 'br':
			decompress = zlib.createBrotliDecompress();
			break;
			case 'deflate':
			decompress = zlib.createInflate();
			break;
			default:
			break;
			}
			if (decompress) {
			_proxyRes.pipe(decompress);
			_proxyRes = decompress;
			}
			return _proxyRes;
			}
			/**
			* Copy original headers
			* https://github.com/apache/superset/blob/9773aba522e957ed9423045ca153219638a85d2f/superset-frontend/webpack.proxy-config.js#L78
			*/
			function copyHeaders(originalResponse, response) {
			response.statusCode = originalResponse.statusCode;
			response.statusMessage = originalResponse.statusMessage;
			if (response.setHeader) {
			let keys = Object.keys(originalResponse.headers);
			// ignore chunked, brotli, gzip, deflate headers
			keys = keys.filter((key) => !['content-encoding', 'transfer-encoding'].includes(key));
			keys.forEach((key) => {
			let value = originalResponse.headers[key];
			if (key === 'set-cookie') {
			// remove cookie domain
			value = Array.isArray(value) ? value : [value];
			value = value.map((x) => x.replace(/Domain=[^;]+?/i, ''));
			}
			response.setHeader(key, value);
			});
			}
			else {
			response.headers = originalResponse.headers;
			}
			}