Make SvgConverter autotaggable.

DEVSIX-8940

Author: guustysebie

commons/src/main/java/com/itextpdf/commons/utils/IOThrowingAction.java

@@ -0,0 +1,39 @@
+/*
+    This file is part of the iText (R) project.
+    Copyright (c) 1998-2025 Apryse Group NV
+    Authors: Apryse Software.
+
+    This program is offered under a commercial and under the AGPL license.
+    For commercial licensing, contact us at https://itextpdf.com/sales.  For AGPL licensing, see below.
+
+    AGPL licensing:
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.itextpdf.commons.utils;
+
+
+import java.io.IOException;
+
+/**
+ * Functional interface which takes 0 parameters and returns nothing and can throw a checked exception.
+ */
+@FunctionalInterface
+public interface IOThrowingAction {
+    /**
+     * Execute action.
+     *
+     * @throws IOException any exception thrown by the encapsulated code
+     */
+    void execute() throws IOException;
+}

commons/src/sharpenconfig/java/com/itextpdf/commons/SharpenConfigMapping.java

@@ -124,6 +124,7 @@ public void applyMappingConfiguration(MappingConfigurator configurator) {
         configurator.mapType("com.itextpdf.commons.utils.ThrowingAction", "System.Action");
         configurator.mapFunctionalInterfaceToDelegate("com.itextpdf.commons.utils.Action");
         configurator.mapFunctionalInterfaceToDelegate("com.itextpdf.commons.utils.ThrowingAction");
+        configurator.mapFunctionalInterfaceToDelegate("com.itextpdf.commons.utils.IOThrowingAction");
         configurator.mapFunctionalInterfaceToDelegate("com.itextpdf.commons.utils.ThrowingSupplier");
         configurator.keepInternalProtected("com.itextpdf.commons.ecosystem.TestConfigurationEvent.doAction");
         configurator.addCustomUsingDeclaration("com.itextpdf.kernel.colors.DeviceRgb", Arrays.asList("iText.Commons.Utils"));

svg/pom.xml

@@ -33,6 +33,12 @@
       <version>${project.version}</version>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>com.itextpdf</groupId>
+      <artifactId>pdfua</artifactId>
+      <version>${project.version}</version>
+      <scope>test</scope>
+    </dependency>
   </dependencies>
 
   <build>

svg/src/main/java/com/itextpdf/svg/converter/SvgConverter.java

@@ -23,13 +23,17 @@ This file is part of the iText (R) project.
 package com.itextpdf.svg.converter;
 
 import com.itextpdf.commons.utils.FileUtil;
+import com.itextpdf.commons.utils.IOThrowingAction;
+import com.itextpdf.kernel.exceptions.PdfException;
 import com.itextpdf.kernel.geom.PageSize;
 import com.itextpdf.kernel.geom.Rectangle;
 import com.itextpdf.kernel.pdf.PdfDocument;
 import com.itextpdf.kernel.pdf.PdfPage;
 import com.itextpdf.kernel.pdf.PdfWriter;
 import com.itextpdf.kernel.pdf.WriterProperties;
 import com.itextpdf.kernel.pdf.canvas.PdfCanvas;
+import com.itextpdf.kernel.pdf.tagging.StandardRoles;
+import com.itextpdf.kernel.pdf.tagutils.TagTreePointer;
 import com.itextpdf.kernel.pdf.xobject.PdfFormXObject;
 import com.itextpdf.layout.element.Image;
 import com.itextpdf.styledxmlparser.IXmlParser;
@@ -48,13 +52,13 @@ This file is part of the iText (R) project.
 import com.itextpdf.svg.renderers.SvgDrawContext;
 import com.itextpdf.svg.renderers.impl.PdfRootSvgNodeRenderer;
 import com.itextpdf.svg.utils.SvgCssUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 /**
  * This is the main container class for static methods that do high-level
@@ -64,11 +68,12 @@ This file is part of the iText (R) project.
  */
 public final class SvgConverter {
 
-    private SvgConverter() {
-    }
-
+    public static final String SVG_DEFAULT_ROLE = StandardRoles.FIGURE;
     private static final Logger LOGGER = LoggerFactory.getLogger(SvgConverter.class);
 
+    private SvgConverter() {
+        //empty constructor
+    }
 
     private static void checkNull(Object o) {
         if (o == null) {
@@ -212,7 +217,13 @@ public static void drawOnPage(String content, PdfPage page) {
      */
     public static void drawOnPage(String content, PdfPage page, float x, float y) {
         checkNull(page);
-        drawOnCanvas(content, new PdfCanvas(page), x, y);
+        PdfCanvas canvas = new PdfCanvas(page);
+        try {
+            withTaggingIfNeeded(page.getDocument(), canvas, page, null, () -> drawOnCanvas(content, canvas, x, y));
+        } catch (IOException e) {
+            // This can't happen in normal circumstances.
+            throw new PdfException(e);
+        }
     }
 
 
@@ -238,7 +249,14 @@ public static void drawOnPage(String content, PdfPage page, ISvgConverterPropert
      */
     public static void drawOnPage(String content, PdfPage page, float x, float y, ISvgConverterProperties props) {
         checkNull(page);
-        drawOnCanvas(content, new PdfCanvas(page), x, y, props);
+        final PdfCanvas canvas = new PdfCanvas(page);
+        try {
+            withTaggingIfNeeded(page.getDocument(), canvas, page, props,
+                    () -> drawOnCanvas(content, canvas, x, y, props));
+        } catch (IOException e) {
+            // This can't happen in normal circumstances.
+            throw new PdfException(e);
+        }
     }
 
     /**
@@ -263,7 +281,8 @@ public static void drawOnPage(InputStream stream, PdfPage page) throws IOExcepti
      */
     public static void drawOnPage(InputStream stream, PdfPage page, float x, float y) throws IOException {
         checkNull(page);
-        drawOnCanvas(stream, new PdfCanvas(page), x, y);
+        PdfCanvas canvas = new PdfCanvas(page);
+        withTaggingIfNeeded(page.getDocument(), canvas, page, null, () -> drawOnCanvas(stream, canvas, x, y));
     }
 
     /**
@@ -288,12 +307,14 @@ public static void drawOnPage(InputStream stream, PdfPage page, ISvgConverterPro
      * @param props  a container for extra properties that customize the behavior
      * @throws IOException when the Stream cannot be read correctly
      */
-    public static void drawOnPage(InputStream stream, PdfPage page, float x, float y, ISvgConverterProperties props) throws IOException {
+    public static void drawOnPage(InputStream stream, PdfPage page, float x, float y, ISvgConverterProperties props)
+            throws IOException {
         checkNull(page);
         if (props instanceof SvgConverterProperties && ((SvgConverterProperties) props).getCustomViewport() == null) {
             ((SvgConverterProperties) props).setCustomViewport(page.getMediaBox());
         }
-        drawOnCanvas(stream, new PdfCanvas(page), x, y, props);
+        PdfCanvas canvas = new PdfCanvas(page);
+        withTaggingIfNeeded(page.getDocument(), canvas, page, props, () -> drawOnCanvas(stream, canvas, x, y, props));
     }
 
     /**
@@ -723,8 +744,18 @@ public static Image convertToImage(InputStream stream, PdfDocument document) thr
      * @return a {@link Image Image} containing the PDF instructions corresponding to the passed SVG content
      * @throws IOException when the Stream cannot be read correctly
      */
-    public static Image convertToImage(InputStream stream, PdfDocument document, ISvgConverterProperties props) throws IOException {
-        return new Image(convertToXObject(stream, document, props));
+    public static Image convertToImage(InputStream stream, PdfDocument document, ISvgConverterProperties props)
+            throws IOException {
+        Image image = new Image(convertToXObject(stream, document, props));
+        if (props instanceof SvgConverterProperties) {
+            SvgConverterProperties properties = (SvgConverterProperties) props;
+            if (properties.getAccessibilityProperties().getAlternateDescription() != null) {
+                image.getAccessibilityProperties()
+                        .setAlternateDescription(properties.getAccessibilityProperties().getAlternateDescription());
+            }
+            image.getAccessibilityProperties().setRole(properties.getAccessibilityProperties().getRole());
+        }
+        return image;
     }
 
     /*
@@ -937,4 +968,35 @@ private static ResourceResolver createResourceResolver(final ISvgConverterProper
         }
         return new ResourceResolver(props.getBaseUri(), props.getResourceRetriever());
     }
+
+
+    private static void withTaggingIfNeeded(PdfDocument document, PdfCanvas canvas, PdfPage page,
+                                            ISvgConverterProperties props, IOThrowingAction function)
+            throws IOException {
+        final boolean isTagged = document.isTagged();
+        if (isTagged) {
+            SvgConverterProperties properties = null;
+            if (props instanceof SvgConverterProperties) {
+                properties = (SvgConverterProperties) props;
+            }
+            String role = SVG_DEFAULT_ROLE;
+            if (properties != null) {
+                role = properties.getAccessibilityProperties().getRole();
+            }
+
+            TagTreePointer tagTreePointer = new TagTreePointer(document);
+            tagTreePointer.addTag(role);
+            tagTreePointer.setPageForTagging(page);
+            if (properties != null && properties.getAccessibilityProperties().getAlternateDescription() != null) {
+                tagTreePointer.getProperties()
+                        .setAlternateDescription(properties.getAccessibilityProperties().getAlternateDescription());
+            }
+            canvas.openTag(tagTreePointer.getTagReference());
+        }
+        function.execute();
+        if (isTagged) {
+            canvas.closeTag();
+        }
+    }
+
 }

svg/src/main/java/com/itextpdf/svg/processors/impl/SvgConverterProperties.java

@@ -23,6 +23,8 @@ This file is part of the iText (R) project.
 package com.itextpdf.svg.processors.impl;
 
 import com.itextpdf.kernel.geom.Rectangle;
+import com.itextpdf.kernel.pdf.tagutils.AccessibilityProperties;
+import com.itextpdf.kernel.pdf.tagutils.DefaultAccessibilityProperties;
 import com.itextpdf.layout.font.FontProvider;
 import com.itextpdf.styledxmlparser.css.CssStyleSheet;
 import com.itextpdf.styledxmlparser.css.media.MediaDeviceDescription;
@@ -34,11 +36,14 @@ This file is part of the iText (R) project.
 
 import java.nio.charset.StandardCharsets;
 
+import static com.itextpdf.svg.converter.SvgConverter.SVG_DEFAULT_ROLE;
+
 /**
  * Default and fallback implementation of {@link ISvgConverterProperties} for
  * {@link DefaultSvgProcessor}.
  */
 public class SvgConverterProperties implements ISvgConverterProperties {
+
     /** The media device description. */
     private MediaDeviceDescription mediaDeviceDescription;
 
@@ -59,6 +64,9 @@ public class SvgConverterProperties implements ISvgConverterProperties {
 
     private Rectangle customViewport = null;
 
+    private final AccessibilityProperties accessibilityProperties = new DefaultAccessibilityProperties(
+            SVG_DEFAULT_ROLE);
+
     /**
      * Creates a new {@link SvgConverterProperties} instance.
      * Instantiates its members, IResourceRetriever and ISvgNodeRendererFactory, to its default implementations.
@@ -80,6 +88,16 @@ public Rectangle getCustomViewport() {
         return customViewport;
     }
 
+
+    /**
+     * Gets the accessibility properties.
+     *
+     * @return the accessibility properties.
+     */
+    public AccessibilityProperties getAccessibilityProperties() {
+        return this.accessibilityProperties;
+    }
+
     /**
      * Sets the custom viewport of SVG.
      * <p>