Initial import from local backup (Documents-Playground/pakerpale)

node_modules/express-http-proxy/app/steps/decorateUserRes.js

@@ -0,0 +1,66 @@
+'use strict';
+
+var as = require('../../lib/as.js');
+var debug = require('debug')('express-http-proxy');
+var zlib = require('zlib');
+
+function isResGzipped(res) {
+  return res.headers['content-encoding'] === 'gzip';
+}
+
+function zipOrUnzip(method) {
+  return function(rspData, res) {
+    return (isResGzipped(res) && rspData.length) ? zlib[method](rspData) : rspData;
+  };
+}
+
+var maybeUnzipResponse = zipOrUnzip('gunzipSync');
+var maybeZipResponse = zipOrUnzip('gzipSync');
+
+function verifyBuffer(rspd, reject) {
+  if (!Buffer.isBuffer(rspd)) {
+    return reject(new Error('userResDecorator should return string or buffer as data'));
+  }
+}
+
+function updateHeaders(res, rspdBefore, rspdAfter, reject) {
+  if (!res.headersSent) {
+      res.set('content-length', rspdAfter.length);
+  } else if (rspdAfter.length !== rspdBefore.length) {
+      var error = '"Content-Length" is already sent,' +
+          'the length of response data can not be changed';
+      return reject(new Error(error));
+  }
+}
+
+function decorateProxyResBody(container) {
+  var resolverFn = container.options.userResDecorator;
+
+  if (!resolverFn) {
+    return Promise.resolve(container);
+  }
+
+  var proxyResData = maybeUnzipResponse(container.proxy.resData, container.proxy.res);
+  var proxyRes = container.proxy.res;
+  var req = container.user.req;
+  var res = container.user.res;
+
+  if (res.statusCode === 304) {
+    debug('Skipping userResDecorator on response 304');
+    return Promise.resolve(container);
+  }
+
+  return Promise
+    .resolve(resolverFn(proxyRes, proxyResData, req, res))
+    .then(function(modifiedResData) {
+      return new Promise(function(resolve, reject) {
+        var rspd = as.buffer(modifiedResData, container.options);
+        verifyBuffer(rspd, reject);
+        updateHeaders(res, proxyResData, rspd, reject);
+        container.proxy.resData = maybeZipResponse(rspd, container.proxy.res);
+        resolve(container);
+      });
+    });
+}
+
+module.exports = decorateProxyResBody;