Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web.Extensions/Script/Services/WebServiceClientProxyGenerator.cs

@@ -0,0 +1,81 @@
+//------------------------------------------------------------------------------
+// <copyright file="WebServiceClientProxyGenerator.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//------------------------------------------------------------------------------
+ 
+namespace System.Web.Script.Services {
+    using System;
+    using System.IO;
+    using System.Reflection;
+    using System.Web;
+    using System.Security.Permissions;
+    using System.Security;
+
+    internal class WebServiceClientProxyGenerator : ClientProxyGenerator {
+        private string _path;
+
+        // Called by ScriptManager to generate the proxy inline
+        internal static string GetInlineClientProxyScript(string path, HttpContext context, bool debug) {
+            WebServiceData webServiceData = WebServiceData.GetWebServiceData(context, path, true, false, true);
+            WebServiceClientProxyGenerator proxyGenerator = new WebServiceClientProxyGenerator(path, debug);
+            return proxyGenerator.GetClientProxyScript(webServiceData);
+        }
+
+        private static DateTime GetAssemblyModifiedTime(Assembly assembly) {
+            AssemblyName assemblyName = assembly.GetName();
+            DateTime writeTime = File.GetLastWriteTime(new Uri(assemblyName.CodeBase).LocalPath);
+            // DevDiv 52056: include writeTime.Second in the date, otherwise if you modify it within the same minute it we'd still respond with http status 304 not modified
+            return new DateTime(writeTime.Year, writeTime.Month, writeTime.Day, writeTime.Hour, writeTime.Minute, writeTime.Second);
+        }
+
+        // This is called thru the RestClientProxyHandler
+        [SecuritySafeCritical]
+        [FileIOPermission(SecurityAction.Assert, Unrestricted = true)]
+        internal static string GetClientProxyScript(HttpContext context) {
+            WebServiceData webServiceData = WebServiceData.GetWebServiceData(context, context.Request.FilePath);
+            DateTime lastModifiedDate = GetAssemblyModifiedTime(webServiceData.TypeData.Type.Assembly);
+
+            // If the browser sent this header, we can check if we need to resend
+            string modifiedSince = context.Request.Headers["If-Modified-Since"];
+            if (modifiedSince != null) {
+                DateTime header;
+                if (DateTime.TryParse(modifiedSince, out header)) {
+                    // We are done if the assembly hasn't been modified
+                    if (header >= lastModifiedDate) {
+                        context.Response.StatusCode = 304;
+                        return null;
+                    }
+                }
+            }
+            bool debug = RestHandlerFactory.IsClientProxyDebugRequest(context.Request.PathInfo);
+            // Only cache for release proxy script (/js)
+            if (!debug) {
+                // Only cache if we get a reasonable last modified date
+                if (lastModifiedDate.ToUniversalTime() < DateTime.UtcNow) {
+                    // Cache the resource so we don't keep processing the same requests
+                    HttpCachePolicy cachePolicy = context.Response.Cache;
+                    cachePolicy.SetCacheability(HttpCacheability.Public);
+                    cachePolicy.SetLastModified(lastModifiedDate);
+                    // expires is necessary so that the browser at least does an If-Modified-Since request on every request.
+                    // without that, the browser wouldn't request a new proxy until the user hits refresh.
+                    // Use one year ago to reasonably ensure "past" interpretation
+                    cachePolicy.SetExpires(lastModifiedDate.AddYears(-1));
+                }
+            }
+
+            WebServiceClientProxyGenerator proxyGenerator = new WebServiceClientProxyGenerator(context.Request.FilePath, debug);
+            return proxyGenerator.GetClientProxyScript(webServiceData);
+        }
+
+        internal WebServiceClientProxyGenerator(string path, bool debug) {
+            // internal because ExtensionsTest needs this path to bypass httpcontext
+            _path = path;
+            _debugMode = debug;
+        }
+
+        protected override string GetProxyPath() {
+            return _path;
+        }
+    }
+}