How to use iText7 to convert HTML to PDF with mixed page orientations while preserving the CSS - itext7

Question

I need to change the page orientation of some parts of a HTML. I followed the accepted answer for this question but the resulting PDF document had neither header nor footer (actually, no style at all).
Here is my first attempt:
package my.awesome.app.html2pdf;
import static com.itextpdf.styledxmlparser.css.media.MediaType.PRINT;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import com.itextpdf.html2pdf.ConverterProperties;
import com.itextpdf.html2pdf.HtmlConverter;
import com.itextpdf.html2pdf.attach.ITagWorker;
import com.itextpdf.html2pdf.attach.ProcessorContext;
import com.itextpdf.html2pdf.attach.impl.DefaultTagWorkerFactory;
import com.itextpdf.html2pdf.attach.impl.tags.DivTagWorker;
import com.itextpdf.kernel.geom.PageSize;
import com.itextpdf.kernel.pdf.PdfDocument;
import com.itextpdf.kernel.pdf.PdfWriter;
import com.itextpdf.layout.Document;
import com.itextpdf.layout.IPropertyContainer;
import com.itextpdf.layout.element.AreaBreak;
import com.itextpdf.layout.element.Div;
import com.itextpdf.layout.element.IBlockElement;
import com.itextpdf.layout.layout.LayoutContext;
import com.itextpdf.layout.layout.LayoutResult;
import com.itextpdf.layout.renderer.AreaBreakRenderer;
import com.itextpdf.styledxmlparser.css.media.MediaDeviceDescription;
import com.itextpdf.styledxmlparser.node.IElementNode;
#RestController
#RequestMapping("/html2pdf")
public class Html2PdfController {
#PostMapping(produces = MediaType.APPLICATION_PDF_VALUE)
public #ResponseBody byte[] convert(#RequestBody String html) throws IOException {
try (var baos = new ByteArrayOutputStream()) {
var mediaDeviceDescription = new MediaDeviceDescription(PRINT);
var converterProperties = new ConverterProperties();
converterProperties.setMediaDeviceDescription(mediaDeviceDescription);
var pdfDocument = new PdfDocument(new PdfWriter(baos));
converterProperties.setTagWorkerFactory(new CustomTagWorkerFactory(pdfDocument));
var document = new Document(pdfDocument);
var elements = HtmlConverter.convertToElements(html, converterProperties);
for (var element : elements) {
if (element instanceof IBlockElement) {
document.add((IBlockElement) element);
}
}
pdfDocument.close();
return baos.toByteArray();
}
}
private static class CustomTagWorkerFactory extends DefaultTagWorkerFactory {
PdfDocument pdfDocument;
public CustomTagWorkerFactory(PdfDocument pdfDocument) {
this.pdfDocument = pdfDocument;
}
#Override
public ITagWorker getCustomTagWorker(IElementNode tag, ProcessorContext context) {
if ("landscape".equalsIgnoreCase(tag.name())) {
return new LandscapeDivTagWorker(tag, context, pdfDocument);
}
return null;
}
}
private static class LandscapeDivTagWorker extends DivTagWorker {
private PdfDocument pdfDocument;
public LandscapeDivTagWorker(IElementNode tag, ProcessorContext context, PdfDocument pdfDocument) {
super(tag, context);
this.pdfDocument = pdfDocument;
}
#Override
public IPropertyContainer getElementResult() {
IPropertyContainer baseElementResult = super.getElementResult();
if (baseElementResult instanceof Div) {
var div = new Div();
var landscapeAreaBreak = new AreaBreak(new PageSize(PageSize.A4).rotate());
landscapeAreaBreak.setNextRenderer(
new DefaultPageSizeChangingAreaBreakRenderer(landscapeAreaBreak, pdfDocument));
div.add(landscapeAreaBreak);
div.add((IBlockElement) baseElementResult);
var portraitAreaBreak = new AreaBreak(new PageSize(PageSize.A4));
portraitAreaBreak.setNextRenderer(
new DefaultPageSizeChangingAreaBreakRenderer(portraitAreaBreak, pdfDocument));
div.add(portraitAreaBreak);
baseElementResult = div;
}
return baseElementResult;
}
}
private static class DefaultPageSizeChangingAreaBreakRenderer extends AreaBreakRenderer {
private PdfDocument pdfDocument;
private AreaBreak areaBreak;
public DefaultPageSizeChangingAreaBreakRenderer(AreaBreak areaBreak, PdfDocument pdfDocument) {
super(areaBreak);
this.pdfDocument = pdfDocument;
this.areaBreak = areaBreak;
}
#Override
public LayoutResult layout(LayoutContext layoutContext) {
pdfDocument.setDefaultPageSize(areaBreak.getPageSize());
return super.layout(layoutContext);
}
}
}
And here is my first result. There is an additional blank page at its end:
After some small changes in the main method:
#PostMapping(produces = MediaType.APPLICATION_PDF_VALUE)
public #ResponseBody byte[] convert(#RequestBody String html) throws IOException {
try (var baos = new ByteArrayOutputStream()) {
var mediaDeviceDescription = new MediaDeviceDescription(PRINT);
var converterProperties = new ConverterProperties();
converterProperties.setMediaDeviceDescription(mediaDeviceDescription);
var pdfDocument = new PdfDocument(new PdfWriter(baos));
converterProperties.setTagWorkerFactory(new CustomTagWorkerFactory(pdfDocument));
var document = HtmlConverter.convertToDocument(html, pdfDocument, converterProperties);
document.close();
pdfDocument.close();
return baos.toByteArray();
}
}
I've got this PDF with nice headers and footers, except for the rotated pages. Also, only the first in a series is in landscape mode:
Actually the landscape pages do have footers, but they are misaligned.
Is there a way to achieve this using iText7 HTML to PDF conversion?