Making C1PageRoute/CmsPageHttpRequest handle page preview requests

Composite/Composite.csproj

@@ -256,14 +256,15 @@
     <Compile Include="Core\Serialization\CompositeJsonSerializer.cs" />
     <Compile Include="Core\Serialization\CompositeSerializationBinder.cs" />
     <Compile Include="Core\WebClient\PageStructureRpc.cs" />
+    <Compile Include="Core\WebClient\Renderings\Page\PagePreviewContext.cs" />
     <Compile Include="Core\WebClient\Renderings\Page\IPageContentFilter.cs" />
     <Compile Include="Core\WebClient\Renderings\INonCachebleRequestHostnameMapper.cs" />
     <Compile Include="Core\WebClient\Services\WampRouter\WampRouteWrapper.cs" />
     <Compile Include="Data\Caching\CachedTable.cs" />
     <Compile Include="Data\Types\IUserGroupActiveLocale.cs" />
     <Compile Include="Data\Types\VersionedDataHelperContract.cs" />
     <Compile Include="Functions\IDynamicFunction.cs" />
-	<Compile Include="Plugins\Elements\ElementProviders\PageElementProvider\PageSearchToken.cs" />
+    <Compile Include="Plugins\Elements\ElementProviders\PageElementProvider\PageSearchToken.cs" />
     <Compile Include="Plugins\Elements\UrlToEntityToken\WebsiteFileUrlToEntityTokenMapper.cs" />
     <Compile Include="Plugins\Elements\UrlToEntityToken\MediaUrlToEntityTokenMapper.cs" />
     <Compile Include="Plugins\Forms\WebChannel\UiControlFactories\TemplatedTreelSelectorUiControlFactory.cs">
@@ -2694,7 +2695,7 @@
   </Target>
   -->
   <Target Name="BeforeBuild">
-  <PropertyGroup>
+    <PropertyGroup>
       <GitBranchFile>$(ProjectDir)git_branch.txt</GitBranchFile>
       <GitCommitHashFile>$(ProjectDir)git_commithash.txt</GitCommitHashFile>
     </PropertyGroup>

Composite/Core/Routing/Pages/C1PageRoute.cs

@@ -1,10 +1,13 @@
-using System;
+using System;
 using System.Globalization;
 using System.Web;
 using System.Web.Routing;
 using Composite.Core.WebClient;
 using Composite.Core.Configuration;
 using Composite.Core.Extensions;
+using Composite.Core.WebClient.Renderings;
+using Composite.Core.WebClient.Renderings.Page;
+using Composite.Search.DocumentSources;
 
 namespace Composite.Core.Routing.Pages
 {
@@ -42,8 +45,7 @@ public static PageUrlData PageUrlData
         /// <returns>The PathInfo url part.</returns>
         public static string GetPathInfo()
         {
-            var urlData = PageUrlData;
-            return urlData != null ? urlData.PathInfo : null;
+            return PageUrlData?.PathInfo;
         }
 
         /// <summary>
@@ -94,13 +96,22 @@ public override RouteData GetRouteData(HttpContextBase context)
 
             string localPath = context.Request.Url.LocalPath;
 
-            var urlProvider = PageUrls.UrlProvider;
+            if (IsPagePreviewPath(localPath) &&
+                PagePreviewContext.TryGetPreviewKey(context.Request, out Guid previewKey))
+            {
+                var page = PagePreviewContext.GetPage(previewKey);
+                if (page == null) throw new InvalidOperationException("Not preview information found by key: " + previewKey);
+
+                return new RouteData(this, new C1PageRouteHandler(new PageUrlData(page)));
+            }
 
             if (UrlUtils.IsAdminConsoleRequest(localPath) || IsRenderersPath(localPath))
             {
                 return null;
             }
 
+            var urlProvider = PageUrls.UrlProvider;
+
             string currentUrl = context.Request.Url.OriginalString;
 
             UrlKind urlKind;
@@ -195,6 +206,11 @@ private static bool IsRenderersPath(string relativeUrl)
             return relativeUrl.StartsWith(UrlUtils.RenderersRootPath + "/", true);
         }
 
+        private static bool IsPagePreviewPath(string relativeUrl)
+        {
+            return relativeUrl.StartsWith($"{UrlUtils.RenderersRootPath}/PagePreview", true);
+        }
+
         private RouteData GetRedirectRoute(string url)
         {
             return new RouteData(this, new SeoFriendlyRedirectRouteHandler(url));

Composite/Core/WebClient/Renderings/Page/PagePreviewBuilder.cs

@@ -1,7 +1,6 @@
 using System;
 using System.Collections.Generic;
 using System.Web;
-using System.Web.Caching;
 using Composite.Data.Types;
 
 namespace Composite.Core.WebClient.Renderings.Page
@@ -13,8 +12,6 @@ namespace Composite.Core.WebClient.Renderings.Page
     [System.ComponentModel.EditorBrowsable(System.ComponentModel.EditorBrowsableState.Never)]
     public class PagePreviewBuilder
     {
-        private static readonly TimeSpan PreviewExpirationTimeSpan = new TimeSpan(0, 20, 0);
-
         /// <summary>
         /// Execute an 'im mem' preview request of the provided page and content. Requires IIS to run in "Integrated" pipeline mode.
         /// </summary>
@@ -41,33 +38,30 @@ public static string RenderPreview(IPage selectedPage, IList<IPagePlaceholderCon
         /// </returns>
         public static string RenderPreview(IPage selectedPage, IList<IPagePlaceholderContent> contents, RenderingReason renderingReason)
         {
-            HttpContext ctx = HttpContext.Current;
-            string key = Guid.NewGuid().ToString();
-            string query = "previewKey=" + key;
-
-            ctx.Cache.Add(key + "_SelectedPage", selectedPage, null, Cache.NoAbsoluteExpiration, PreviewExpirationTimeSpan, CacheItemPriority.NotRemovable, null);
-            ctx.Cache.Add(key + "_SelectedContents", contents, null, Cache.NoAbsoluteExpiration, PreviewExpirationTimeSpan, CacheItemPriority.NotRemovable, null);
-            ctx.Cache.Add(key + "_RenderingReason", renderingReason, null, Cache.NoAbsoluteExpiration, PreviewExpirationTimeSpan, CacheItemPriority.NotRemovable, null);
-
             if (!HttpRuntime.UsingIntegratedPipeline)
             {
                 throw new InvalidOperationException("IIS classic mode not supported");
             }
 
+            var previewKey = Guid.NewGuid();
+            PagePreviewContext.Save(previewKey, selectedPage, contents, renderingReason);
+
             // The header trick here is to work around (what seems to be) a bug in .net 4.5, where preserveForm=false is ignored
             // asp.net 4.5 request validation will see the 'page edit http post' data and start bitching. It really should not.
             var headers = new System.Collections.Specialized.NameValueCollection
             {
                 {"Content-Length", "0"}
             };
 
+            var ctx = HttpContext.Current;
             string cookieHeader = ctx.Request.Headers["Cookie"];
             if (!string.IsNullOrEmpty(cookieHeader))
             {
                 headers.Add("Cookie", cookieHeader);
             }
 
-            ctx.Server.TransferRequest("~/Renderers/Page.aspx?" + query, false, "GET", headers);
+            string previewPath = $"~/Renderers/PagePreview?{PagePreviewContext.PreviewKeyUrlParameter}={previewKey}";
+            ctx.Server.TransferRequest(previewPath, false, "GET", headers);
 
             return String.Empty;
         }

Composite/Core/WebClient/Renderings/Page/PagePreviewContext.cs

@@ -0,0 +1,69 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.Specialized;
+using System.Web;
+using System.Web.Caching;
+using Composite.Data.Types;
+
+namespace Composite.Core.WebClient.Renderings.Page
+{
+    internal static class PagePreviewContext
+    {
+        public static readonly string PreviewKeyUrlParameter = "previewKey";
+
+        private static readonly TimeSpan PreviewExpirationTimeSpan = new TimeSpan(0, 20, 0);
+
+        private static string CacheKey_Page(Guid key) => key + "_SelectedPage";
+        private static string CacheKey_Contents(Guid key) => key + "_SelectedContents";
+        private static string CacheKey_RenderingReason(Guid key) => key + "_RenderingReason";
+
+        public static void Save(Guid previewKey, IPage selectedPage, IList<IPagePlaceholderContent> contents, RenderingReason renderingReason)
+        {
+            var cache = HttpRuntime.Cache;
+
+            cache.Add(CacheKey_Page(previewKey), selectedPage, null, Cache.NoAbsoluteExpiration, PreviewExpirationTimeSpan, CacheItemPriority.NotRemovable, null);
+            cache.Add(CacheKey_Contents(previewKey), contents, null, Cache.NoAbsoluteExpiration, PreviewExpirationTimeSpan, CacheItemPriority.NotRemovable, null);
+            cache.Add(CacheKey_RenderingReason(previewKey), renderingReason, null, Cache.NoAbsoluteExpiration, PreviewExpirationTimeSpan, CacheItemPriority.NotRemovable, null);
+        }
+
+        public static bool TryGetPreviewKey(HttpRequest request, out Guid previewKey)
+        {
+            return TryGetPreviewKey(request.QueryString, out previewKey);
+        }
+
+        public static bool TryGetPreviewKey(HttpRequestBase request, out Guid previewKey)
+        {
+            return TryGetPreviewKey(request.QueryString, out previewKey);
+        }
+
+        private static bool TryGetPreviewKey(NameValueCollection queryString, out Guid previewKey)
+        {
+            var value = queryString[PreviewKeyUrlParameter];
+            if (!string.IsNullOrWhiteSpace(value) && Guid.TryParse(value, out previewKey))
+            {
+                return true;
+            }
+
+            previewKey = Guid.Empty;
+            return false;
+        }
+
+        public static IPage GetPage(Guid previewKey)
+            => (IPage) HttpRuntime.Cache.Get(CacheKey_Page(previewKey));
+
+        public static IList<IPagePlaceholderContent> GetPageContents(Guid previewKey)
+            => (IList<IPagePlaceholderContent>)HttpRuntime.Cache.Get(CacheKey_Contents(previewKey));
+
+        public static RenderingReason GetRenderingReason(Guid previewKey)
+            => (RenderingReason)HttpRuntime.Cache.Get(CacheKey_RenderingReason(previewKey));
+
+        public static void Remove(Guid previewKey)
+        {
+            var cache = HttpRuntime.Cache;
+
+            cache.Remove(CacheKey_Page(previewKey));
+            cache.Remove(CacheKey_Contents(previewKey));
+            cache.Remove(CacheKey_RenderingReason(previewKey));
+        }
+    }
+}

Composite/Core/WebClient/Renderings/RenderingContext.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.Text;
 using System.Threading;
@@ -54,7 +54,7 @@ public sealed class RenderingContext: IDisposable
         private static readonly List<string> _prettifyErrorUrls = new List<string>();
         private static int _prettifyErrorCount;
 
-        private string _previewKey;
+        private Guid _previewKey;
         private IDisposable _pagePerfMeasuring;
         private string _cachedUrl;
         private IDisposable _dataScope;
@@ -115,7 +115,7 @@ public bool RunResponseHandlers()
         /// <exclude />
         public IEnumerable<IPagePlaceholderContent> GetPagePlaceholderContents()
         {
-            return PreviewMode ? (IEnumerable<IPagePlaceholderContent>)HttpRuntime.Cache.Get(_previewKey + "_SelectedContents")
+            return PreviewMode ? PagePreviewContext.GetPageContents(_previewKey)
                                : PageManager.GetPlaceholderContent(Page.Id, Page.VersionId);
         }
 
@@ -204,15 +204,13 @@ private void InitializeFromHttpContextInternal()
                 _pagePerfMeasuring = Profiler.Measure("C1 Page");
             }
 
-            _previewKey = request.QueryString["previewKey"];
-            PreviewMode = !_previewKey.IsNullOrEmpty();
+            PreviewMode = PagePreviewContext.TryGetPreviewKey(request, out _previewKey);
 
             if (PreviewMode)
             {
-                Page = (IPage)HttpRuntime.Cache.Get(_previewKey + "_SelectedPage");
+                Page = PagePreviewContext.GetPage(_previewKey);
                 C1PageRoute.PageUrlData = new PageUrlData(Page);
-
-                PageRenderer.RenderingReason = (RenderingReason) HttpRuntime.Cache.Get(_previewKey + "_RenderingReason");
+                PageRenderer.RenderingReason = PagePreviewContext.GetRenderingReason(_previewKey);
             }
             else
             {
@@ -326,10 +324,7 @@ public void Dispose()
 
             if (PreviewMode)
             {
-                var cache = HttpRuntime.Cache;
-
-                cache.Remove(_previewKey + "_SelectedPage");
-                cache.Remove(_previewKey + "_SelectedContents");
+                PagePreviewContext.Remove(_previewKey);
             }
         }
     }