Merge pull request #3902 from michael-hawker/doc-caching-fix

Fix Remote Doc/Image Caching in Sample App

Author: michael-hawker

Microsoft.Toolkit.Uwp.SampleApp/Microsoft.Toolkit.Uwp.SampleApp.csproj

@@ -37,7 +37,7 @@
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|x86'">
     <OutputPath>bin\x86\Release\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
+    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP;REMOTE_DOCS</DefineConstants>
     <Optimize>true</Optimize>
     <NoWarn>;2008</NoWarn>
     <DebugType>pdbonly</DebugType>
@@ -63,7 +63,7 @@
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|ARM'">
     <OutputPath>bin\ARM\Release\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
+    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP;REMOTE_DOCS</DefineConstants>
     <Optimize>true</Optimize>
     <NoWarn>;2008</NoWarn>
     <DebugType>pdbonly</DebugType>
@@ -89,7 +89,7 @@
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|x64'">
     <OutputPath>bin\x64\Release\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
+    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP;REMOTE_DOCS</DefineConstants>
     <Optimize>true</Optimize>
     <NoWarn>;2008</NoWarn>
     <DebugType>pdbonly</DebugType>
@@ -1484,7 +1484,7 @@
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|ARM64'">
     <OutputPath>bin\ARM64\Release\</OutputPath>
-    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP</DefineConstants>
+    <DefineConstants>TRACE;NETFX_CORE;WINDOWS_UWP;REMOTE_DOCS</DefineConstants>
     <Optimize>true</Optimize>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
     <NoWarn>;2008</NoWarn>

Microsoft.Toolkit.Uwp.SampleApp/Models/Sample.cs

@@ -115,7 +115,7 @@ public string CodeUrl
 
             set
             {
-#if DEBUG
+#if !REMOTE_DOCS
                 _codeUrl = value;
 #else
                 var regex = new Regex("^https://github.com/windows-toolkit/WindowsCommunityToolkit/(tree|blob)/(?<branch>.+?)/(?<path>.*)");
@@ -221,12 +221,13 @@ public async Task<string> GetDocumentationAsync()
             if (docMatch.Success)
             {
                 filepath = docMatch.Groups["file"].Value;
-                filename = Path.GetFileName(RemoteDocumentationPath);
+                filename = Path.GetFileName(filepath);
+
                 RemoteDocumentationPath = Path.GetDirectoryName(filepath);
-                LocalDocumentationFilePath = $"ms-appx:///docs/{RemoteDocumentationPath}/";
+                LocalDocumentationFilePath = $"ms-appx:///docs/{filepath}/";
             }
 
-#if !DEBUG // use the docs repo in release mode
+#if REMOTE_DOCS // use the docs repo in release mode
             string modifiedDocumentationUrl = $"{_docsOnlineRoot}live/docs/{filepath}";
 
             // Read from Cache if available.
@@ -285,6 +286,11 @@ public async Task<string> GetDocumentationAsync()
             return _cachedDocumentation;
         }
 
+        public Uri GetOnlineResourcePath(string relativePath)
+        {
+            return new Uri($"{_docsOnlineRoot}live/docs/{RemoteDocumentationPath}/{relativePath}");
+        }
+
         /// <summary>
         /// Gets the image data from a Uri, with Caching.
         /// </summary>
@@ -301,45 +307,61 @@ async Task<Stream> CopyStream(HttpContent source)
             }
 
             IRandomAccessStream imageStream = null;
-            var localPath = $"{uri.Host}/{uri.LocalPath}";
+            var localPath = $"{uri.Host}/{uri.LocalPath}".Replace("//", "/");
+
+            if (localPath.StartsWith(_docsOnlineRoot.Substring(8)))
+            {
+                // If we're looking for docs we should look in our local area first.
+                localPath = localPath.Substring(_docsOnlineRoot.Length - 3); // want to chop "live/" but missing https:// as well.
+            }
 
-            // Cache only in Release
-#if !DEBUG
+            // Try cache only in Release (using remote docs)
+#if REMOTE_DOCS
             try
             {
                 imageStream = await StreamHelper.GetLocalCacheFileStreamAsync(localPath, Windows.Storage.FileAccessMode.Read);
             }
             catch
             {
             }
-#endif
 
             if (imageStream == null)
             {
                 try
                 {
+                    // Our docs don't reference any external images, this should only be for getting latest image from repo.
                     using (var response = await client.GetAsync(uri))
                     {
                         if (response.IsSuccessStatusCode)
                         {
                             var imageCopy = await CopyStream(response.Content);
                             imageStream = imageCopy.AsRandomAccessStream();
 
-                            // Cache only in Release
-#if !DEBUG
                             // Takes a second copy of the image stream, so that is can save the image data to cache.
                             using (var saveStream = await CopyStream(response.Content))
                             {
                                 await SaveImageToCache(localPath, saveStream);
                             }
-#endif
                         }
                     }
                 }
                 catch
                 {
                 }
             }
+#endif
+
+            // If we don't have internet, then try to see if we have a packaged copy
+            if (imageStream == null)
+            {
+                try
+                {
+                    imageStream = await StreamHelper.GetPackagedFileStreamAsync(localPath);
+                }
+                catch
+                {
+                }
+            }
 
             return imageStream;
         }

Microsoft.Toolkit.Uwp.SampleApp/Pages/SampleController.xaml.cs

@@ -453,15 +453,21 @@ private async void DocumentationTextBlock_ImageResolving(object sender, ImageRes
             // Determine if the link is not absolute, meaning it is relative.
             if (!Uri.TryCreate(e.Url, UriKind.Absolute, out Uri url))
             {
-                url = new Uri(CurrentSample.LocalDocumentationFilePath + e.Url);
-            }
+                var imageStream = await CurrentSample.GetImageStream(CurrentSample.GetOnlineResourcePath(e.Url));
 
-            if (url.Scheme == "ms-appx")
+                if (imageStream != null)
+                {
+                    image = new BitmapImage();
+                    await image.SetSourceAsync(imageStream);
+                }
+            }
+            else if (url.Scheme == "ms-appx")
             {
                 image = new BitmapImage(url);
             }
             else
             {
+                // Cache a remote image from the internet.
                 var imageStream = await CurrentSample.GetImageStream(url);
 
                 if (imageStream != null)