Apply browser defaults in case of missing w or h

Apply browser default values when height or width is missing from the top-level SVG

RND-1011

Author: Samuel Huylebroeck

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

@@ -54,6 +54,7 @@ This file is part of the iText (R) project.
 import com.itextpdf.layout.element.Image;
 import com.itextpdf.styledxmlparser.IXmlParser;
 import com.itextpdf.styledxmlparser.css.util.CssUtils;
+import com.itextpdf.styledxmlparser.exceptions.StyledXMLParserException;
 import com.itextpdf.styledxmlparser.node.INode;
 import com.itextpdf.styledxmlparser.node.impl.jsoup.JsoupXmlParser;
 import com.itextpdf.styledxmlparser.resolver.resource.ResourceResolver;
@@ -68,12 +69,17 @@ This file is part of the iText (R) project.
 import com.itextpdf.svg.renderers.ISvgNodeRenderer;
 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.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
+import java.util.List;
 
 /**
  * This is the main container class for static methods that do high-level
@@ -86,6 +92,9 @@ public final class SvgConverter {
     private SvgConverter() {
     }
 
+    private static final Logger LOGGER = LoggerFactory.getLogger(SvgConverter.class);
+
+
     private static void checkNull(Object o) {
         if (o == null) {
             throw new SvgProcessingException(SvgLogMessageConstant.PARAMETER_CANNOT_BE_NULL);
@@ -546,8 +555,12 @@ public static void createPdf(InputStream svgStream, OutputStream pdfDest, ISvgCo
         //Extract topmost dimensions
         checkNull(topSvgRenderer);
         checkNull(pdfDocument);
-        float width = CssUtils.parseAbsoluteLength(topSvgRenderer.getAttribute(SvgConstants.Attributes.WIDTH));
-        float height = CssUtils.parseAbsoluteLength(topSvgRenderer.getAttribute(SvgConstants.Attributes.HEIGHT));
+        float width, height;
+
+        float[] wh = extractWidthAndHeight(topSvgRenderer);
+        width = wh[0];
+        height = wh[1];
+
         //adjust pagesize and create new page
         pdfDocument.setDefaultPageSize(new PageSize(width, height));
         PdfPage page = pdfDocument.addNewPage();
@@ -789,9 +802,12 @@ private static PdfFormXObject convertToXObject(ISvgNodeRenderer topSvgRenderer,
         checkNull(topSvgRenderer);
         checkNull(document);
         checkNull(context);
+        float width, height;
+
+        float[] wh = extractWidthAndHeight(topSvgRenderer);
+        width = wh[0];
+        height = wh[1];
 
-        float width = CssUtils.parseAbsoluteLength(topSvgRenderer.getAttribute(SvgConstants.Attributes.WIDTH));
-        float height = CssUtils.parseAbsoluteLength(topSvgRenderer.getAttribute(SvgConstants.Attributes.HEIGHT));
         PdfFormXObject pdfForm = new PdfFormXObject(new Rectangle(0, 0, width, height));
         PdfCanvas canvas = new PdfCanvas(pdfForm, document);
 
@@ -896,4 +912,61 @@ public static INode parse(InputStream stream, ISvgConverterProperties props) thr
         IXmlParser xmlParser = new JsoupXmlParser();
         return xmlParser.parse(stream, props != null ? props.getCharset() : null);
     }
+
+    /**
+     * Extract width and height of the passed SVGNodeRenderer,
+     * defaulting to respective viewbox values if either one is not present or
+     * to browser default if viewbox is missing as well
+     *
+     * @return float[2], width is in position 0, height in position 1
+     */
+    private static float[] extractWidthAndHeight(ISvgNodeRenderer topSvgRenderer) {
+        float[] res = new float[2];
+        boolean viewBoxPresent = false;
+
+        //Parse viewbox
+        String vbString = topSvgRenderer.getAttribute(SvgConstants.Attributes.VIEWBOX);
+        float[] values = {0, 0, 0, 0};
+        if (vbString != null) {
+            List<String> valueStrings = SvgCssUtils.splitValueList(vbString);
+            values = new float[valueStrings.size()];
+            for (int i = 0; i < values.length; i++) {
+                values[i] = CssUtils.parseAbsoluteLength(valueStrings.get(i));
+            }
+        }
+        float width, height;
+        String wString, hString;
+        wString = topSvgRenderer.getAttribute(SvgConstants.Attributes.WIDTH);
+        if (wString == null) {
+            //Log Warning
+            LOGGER.warn(SvgLogMessageConstant.MISSING_WIDTH);
+            if (viewBoxPresent) {
+                width = values[2];
+            } else {
+                //Set to browser default
+                width = CssUtils.parseAbsoluteLength("300px");
+            }
+        } else {
+            width = CssUtils.parseAbsoluteLength(wString);
+        }
+        hString = topSvgRenderer.getAttribute(SvgConstants.Attributes.HEIGHT);
+        if (hString == null) {
+            //Log Warning
+            LOGGER.warn(SvgLogMessageConstant.MISSING_HEIGHT);
+            if (viewBoxPresent) {
+                height = values[3];
+            } else {
+                //Set to browser default
+                height = CssUtils.parseAbsoluteLength("150px");
+            }
+        } else {
+            height = CssUtils.parseAbsoluteLength(hString);
+        }
+
+        res[0] = width;
+        res[1] = height;
+        return res;
+
+
+    }
 }

src/main/java/com/itextpdf/svg/exceptions/SvgLogMessageConstant.java

@@ -63,6 +63,8 @@ public final class SvgLogMessageConstant {
     public static final String INVALID_PATH_D_ATTRIBUTE_OPERATORS = "Invalid operators found in path data attribute: {0}";
     public static final String INVALID_TRANSFORM_DECLARATION = "Transformation declaration is not formed correctly.";
     public static final String LOOP ="Loop detected";
+    public static final String MISSING_WIDTH="Top Svg tag has no defined width attribute and viewbox width is not present, so browser default of 300px is used";
+    public static final String MISSING_HEIGHT="Top Svg tag has no defined height attribute and viewbox height is not present, so browser default of 150px is used";
     public static final String NAMED_OBJECT_NAME_NULL_OR_EMPTY = "The name of the named object can't be null or empty.";
     public static final String NAMED_OBJECT_NULL = "A named object can't be null.";
     public static final String NOROOT = "No root found";

src/test/java/com/itextpdf/svg/renderers/impl/SimpleSvgTagSvgNodeRendererIntegrationTest.java

@@ -76,35 +76,24 @@ public void everythingPresentAndValidTest() throws IOException, InterruptedExcep
         convertAndCompareVisually(SOURCE_FOLDER, DESTINATION_FOLDER,"everythingPresentAndValid");
     }
 
-    @Test
-    public void absentEverything() throws IOException, InterruptedException {
-        junitExpectedException.expect(StyledXMLParserException.class);
-        junitExpectedException.expectMessage(MessageFormatUtil.format(LogMessageConstant.NAN, "null"));
-        convertAndCompareVisually(SOURCE_FOLDER, DESTINATION_FOLDER,"absentEverything");
-
-    }
-
     @Test
     public void absentHeight() throws IOException, InterruptedException {
-        junitExpectedException.expect(StyledXMLParserException.class);
-        junitExpectedException.expectMessage(MessageFormatUtil.format(LogMessageConstant.NAN, "null"));
         convertAndCompareVisually(SOURCE_FOLDER, DESTINATION_FOLDER,"absentHeight");
-
     }
 
     @Test
     public void absentWidth() throws IOException, InterruptedException {
-        junitExpectedException.expect(StyledXMLParserException.class);
-        junitExpectedException.expectMessage(MessageFormatUtil.format(LogMessageConstant.NAN, "null"));
         convertAndCompareVisually(SOURCE_FOLDER, DESTINATION_FOLDER,"absentWidth");
     }
 
     @Test
     public void absentWidthAndHeight() throws IOException, InterruptedException {
-        junitExpectedException.expect(StyledXMLParserException.class);
-        junitExpectedException.expectMessage(MessageFormatUtil.format(LogMessageConstant.NAN, "null"));
         convertAndCompareVisually(SOURCE_FOLDER, DESTINATION_FOLDER,"absentWidthAndHeight");
+    }
 
+    @Test
+    public void absentWHViewboxPresent() throws IOException, InterruptedException {
+        convertAndCompareVisually(SOURCE_FOLDER, DESTINATION_FOLDER,"absentWHViewboxPresent");
     }
 
     @Test