Display infobar for blocked relative image path (#1695)

* Updated Parsing extension to show infobar when relative URL isblocked and updated corresponding tests

* Updated Controller to display infobar when html img tag is embedded in markdown

src/modules/previewpane/MarkDownPreviewHandler/HTMLParsingExtension.cs

@@ -1,117 +1,103 @@
-// Copyright (c) Microsoft Corporation
+// Copyright (c) Microsoft Corporation
-// The Microsoft Corporation licenses this file to you under the MIT license.
+// The Microsoft Corporation licenses this file to you under the MIT license.
-// See the LICENSE file in the project root for more information.
+// See the LICENSE file in the project root for more information.
-
+
-using System;
+using System;
-using System.IO;
+using System.IO;
-using Markdig;
+using Markdig;
-using Markdig.Extensions.Figures;
+using Markdig.Extensions.Figures;
-using Markdig.Extensions.Tables;
+using Markdig.Extensions.Tables;
-using Markdig.Renderers;
+using Markdig.Renderers;
-using Markdig.Renderers.Html;
+using Markdig.Renderers.Html;
-using Markdig.Syntax;
+using Markdig.Syntax;
-using Markdig.Syntax.Inlines;
+using Markdig.Syntax.Inlines;
-
+
-namespace MarkdownPreviewHandler
+namespace MarkdownPreviewHandler
-{
+{
     /// <summary>
     /// Callback if extension blocks external images.
     /// </summary>
     public delegate void ImagesBlockedCallBack();
 
-    /// <summary>
+    /// <summary>
-    /// Markdig Extension to process html nodes in markdown AST.
+    /// Markdig Extension to process html nodes in markdown AST.
-    /// </summary>
+    /// </summary>
-    public class HTMLParsingExtension : IMarkdownExtension
+    public class HTMLParsingExtension : IMarkdownExtension
-    {
+    {
         /// <summary>
         /// Callback if extension blocks external images.
-        /// </summary>
+        /// </summary>
-        private readonly ImagesBlockedCallBack imagesBlockedCallBack;
+        private readonly ImagesBlockedCallBack imagesBlockedCallBack;
-
+
         /// <summary>
         /// Initializes a new instance of the <see cref="HTMLParsingExtension"/> class.
         /// </summary>
         /// <param name="imagesBlockedCallBack">Callback function if image is blocked by extension.</param>
-        /// <param name="baseUrl">Absolute path of markdown file.</param>
+        /// <param name="baseUrl">Absolute path of markdown file.</param>
-        public HTMLParsingExtension(ImagesBlockedCallBack imagesBlockedCallBack, string baseUrl = "")
+        public HTMLParsingExtension(ImagesBlockedCallBack imagesBlockedCallBack, string baseUrl = "")
-        {
+        {
-            this.imagesBlockedCallBack = imagesBlockedCallBack;
+            this.imagesBlockedCallBack = imagesBlockedCallBack;
-            this.BaseUrl = baseUrl;
+            this.BaseUrl = baseUrl;
-        }
+        }
 
-        /// <summary>
+        /// <summary>
-        /// Gets or sets path to directory containing markdown file.
+        /// Gets or sets path to directory containing markdown file.
-        /// </summary>
+        /// </summary>
-        public string BaseUrl { get; set; }
+        public string BaseUrl { get; set; }
 
-        /// <inheritdoc/>
+        /// <inheritdoc/>
-        public void Setup(MarkdownPipelineBuilder pipeline)
+        public void Setup(MarkdownPipelineBuilder pipeline)
-        {
+        {
-            // Make sure we don't have a delegate twice
+            // Make sure we don't have a delegate twice
-            pipeline.DocumentProcessed -= this.PipelineOnDocumentProcessed;
+            pipeline.DocumentProcessed -= this.PipelineOnDocumentProcessed;
-            pipeline.DocumentProcessed += this.PipelineOnDocumentProcessed;
+            pipeline.DocumentProcessed += this.PipelineOnDocumentProcessed;
-        }
+        }
-
+
-        /// <inheritdoc/>
+        /// <inheritdoc/>
-        public void Setup(MarkdownPipeline pipeline, IMarkdownRenderer renderer)
+        public void Setup(MarkdownPipeline pipeline, IMarkdownRenderer renderer)
-        {
+        {
-        }
+        }
-
+
-        /// <summary>
+        /// <summary>
-        /// Process nodes in markdown AST.
+        /// Process nodes in markdown AST.
-        /// </summary>
+        /// </summary>
-        /// <param name="document">Markdown Document.</param>
+        /// <param name="document">Markdown Document.</param>
-        public void PipelineOnDocumentProcessed(MarkdownDocument document)
+        public void PipelineOnDocumentProcessed(MarkdownDocument document)
-        {
+        {
-            foreach (var node in document.Descendants())
+            foreach (var node in document.Descendants())
             {
-                if (node is Block)
+                if (node is Block)
-                {
+                {
-                    if (node is Table)
+                    if (node is Table)
-                    {
+                    {
-                        node.GetAttributes().AddClass("table table-striped table-bordered");
+                        node.GetAttributes().AddClass("table table-striped table-bordered");
-                    }
+                    }
-                    else if (node is QuoteBlock)
+                    else if (node is QuoteBlock)
-                    {
+                    {
-                        node.GetAttributes().AddClass("blockquote");
+                        node.GetAttributes().AddClass("blockquote");
-                    }
+                    }
-                    else if (node is Figure)
+                    else if (node is Figure)
-                    {
+                    {
-                        node.GetAttributes().AddClass("figure");
+                        node.GetAttributes().AddClass("figure");
-                    }
+                    }
-                    else if (node is FigureCaption)
+                    else if (node is FigureCaption)
-                    {
+                    {
-                        node.GetAttributes().AddClass("figure-caption");
+                        node.GetAttributes().AddClass("figure-caption");
-                    }
+                    }
-                }
+                }
-                else if (node is Inline)
+                else if (node is Inline)
-                {
+                {
-                    if (node is LinkInline link)
+                    if (node is LinkInline link)
-                    {
+                    {
                         if (link.IsImage)
                         {
+                            link.Url = "#";
                             link.GetAttributes().AddClass("img-fluid");
-                        }
+                            this.imagesBlockedCallBack();
-
+                        }
-                        if (!Uri.TryCreate(link.Url, UriKind.Absolute, out _))
+                    }
-                        {
+                }
-                            link.Url = link.Url.TrimStart('/', '\\');
+            }
-                            this.BaseUrl = this.BaseUrl.TrimEnd('/', '\\');
+        }
-                            Uri uriLink = new Uri(Path.Combine(this.BaseUrl, link.Url));
+    }
-                            link.Url = uriLink.ToString();
+}
-                        }
-                        else
-                        {
-                            if (link.IsImage)
-                            {
-                                link.Url = "#";
-                                this.imagesBlockedCallBack();
-                            }
-                        }
-                    }
-                }
-            }
-        }
-    }
-}

src/modules/previewpane/MarkdownPreviewHandler/MarkdownPreviewHandlerControl.cs

@@ -8,6 +8,7 @@ using System.Drawing;
 using System.IO;
 using System.Linq;
 using System.Text;
+using System.Text.RegularExpressions;
 using System.Windows.Forms;
 using Common;
 using Markdig;
@@ -83,6 +84,12 @@ namespace MarkdownPreviewHandler
                     string fileText = File.ReadAllText(filePath);
                     this.extension.BaseUrl = Path.GetDirectoryName(filePath);
 
+                    Regex rgx = new Regex(@"<[ ]*img.*>");
+                    if (rgx.IsMatch(fileText))
+                    {
+                        this.infoBarDisplayed = true;
+                    }
+
                     MarkdownPipeline pipeline = this.pipelineBuilder.Build();
                     string parsedMarkdown = Markdown.ToHtml(fileText, pipeline);
                     sb.AppendFormat("{0}{1}{2}", this.htmlHeader, parsedMarkdown, this.htmlFooter);

src/modules/previewpane/PreviewPaneUnitTests/HTMLParsingExtensionTest.cs

@@ -47,7 +47,7 @@ namespace PreviewPaneUnitTests
         }
 
         [TestMethod]
-        public void Extension_UpdatesFigureClassAndRelativeUrltoAbsolute_WhenUsed()
+        public void Extension_UpdatesFigureClassAndBlocksRelativeUrl_WhenUsed()
         {
             // arrange 
             String mdString = "![text](a.jpg \"Figure\")";
@@ -58,37 +58,7 @@ namespace PreviewPaneUnitTests
             String html = Markdown.ToHtml(mdString, markdownPipeline);
 
             // Assert
-            Assert.AreEqual(html, "<p><img src=\"file:///C:/Users/a.jpg\" class=\"img-fluid\" alt=\"text\" title=\"Figure\" /></p>\n");
+            Assert.AreEqual(html, "<p><img src=\"#\" class=\"img-fluid\" alt=\"text\" title=\"Figure\" /></p>\n");
-        }
-
-        [TestMethod]
-        public void Extension_CreatesCorrectAbsoluteLinkByTrimmingForwardSlash_WhenUsed()
-        {
-            // arrange 
-            String mdString = "![text](\\document\\a.jpg \"Figure\")";
-            HTMLParsingExtension htmlParsingExtension = new HTMLParsingExtension(() => { }, "C:\\Users\\");
-            MarkdownPipeline markdownPipeline = BuidPipeline(htmlParsingExtension);
-
-            // Act
-            String html = Markdown.ToHtml(mdString, markdownPipeline);
-
-            // Assert
-            Assert.AreEqual(html, "<p><img src=\"file:///C:/Users/document/a.jpg\" class=\"img-fluid\" alt=\"text\" title=\"Figure\" /></p>\n");
-        }
-
-        [TestMethod]
-        public void Extension_CreatesCorrectAbsoluteLinkByTrimmingBackwardSlash_WhenUsed()
-        {
-            // arrange 
-            String mdString = "![text](/document/a.jpg \"Figure\")";
-            HTMLParsingExtension htmlParsingExtension = new HTMLParsingExtension(() => { }, "C:/Users/");
-            MarkdownPipeline markdownPipeline = BuidPipeline(htmlParsingExtension);
-
-            // Act
-            String html = Markdown.ToHtml(mdString, markdownPipeline);
-
-            // Assert
-            Assert.AreEqual(html, "<p><img src=\"file:///C:/Users/document/a.jpg\" class=\"img-fluid\" alt=\"text\" title=\"Figure\" /></p>\n");
         }
 
         [TestMethod]

src/modules/previewpane/PreviewPaneUnitTests/HelperFiles/MarkdownWithHTMLImageTag.txt

@@ -0,0 +1,2 @@
+## Something
+<img src="./a.jpg" \>

src/modules/previewpane/PreviewPaneUnitTests/MarkdownPreviewHandlerTest.cs

@@ -42,6 +42,20 @@ namespace PreviewPaneUnitTests
             Assert.IsInstanceOfType(markdownPreviewHandlerControl.Controls[1], typeof(RichTextBox));
         }
 
+        [TestMethod]
+        public void MarkdownPreviewHandlerControl__AddsInfoBarToFormIfHTMLImageTagIsPresent_WhenDoPreviewIsCalled()
+        {
+            // Arrange 
+            MarkdownPreviewHandlerControl markdownPreviewHandlerControl = new MarkdownPreviewHandlerControl();
+
+            // Act
+            markdownPreviewHandlerControl.DoPreview<string>("HelperFiles/MarkdownWithHTMLImageTag.txt");
+
+            // Assert
+            Assert.AreEqual(markdownPreviewHandlerControl.Controls.Count, 2);
+            Assert.IsInstanceOfType(markdownPreviewHandlerControl.Controls[1], typeof(RichTextBox));
+        }
+
         [TestMethod]
         public void MarkdownPreviewHandlerControl__DoesNotAddInfoBarToFormIfExternalImageLinkNotPresent_WhenDoPreviewIsCalled()
         {

src/modules/previewpane/PreviewPaneUnitTests/UnitTests-MarkdownPreviewHandler.csproj

@@ -116,6 +116,9 @@
     <Content Include="HelperFiles\MarkdownWithExternalImage.txt">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
+    <Content Include="HelperFiles\MarkdownWithHTMLImageTag.txt">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
     <Content Include="HelperFiles\MarkdownWithscript.txt">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>