#356 Added cli parameter to generate basic pdf version of xml report

library/src/main/java/org/mustangproject/ZUGFeRD/ValidationLogVisualizer.java

@@ -0,0 +1,148 @@
+package org.mustangproject.ZUGFeRD;
+
+import org.apache.fop.apps.*;
+import org.apache.fop.apps.io.ResourceResolverFactory;
+import org.apache.fop.configuration.Configuration;
+import org.apache.fop.configuration.ConfigurationException;
+import org.apache.fop.configuration.DefaultConfigurationBuilder;
+import org.apache.xmlgraphics.util.MimeConstants;
+import org.mustangproject.ClasspathResolverURIAdapter;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.xml.transform.*;
+import javax.xml.transform.sax.SAXResult;
+import javax.xml.transform.stream.StreamResult;
+import javax.xml.transform.stream.StreamSource;
+import java.io.*;
+import java.nio.charset.StandardCharsets;
+
+public class ValidationLogVisualizer {
+	public enum Language {
+		EN,
+		FR,
+		DE
+	}
+
+	static final ClassLoader CLASS_LOADER = ValidationLogVisualizer.class.getClassLoader();
+	private static final String RESOURCE_PATH = "";
+	private static final Logger LOGGER = LoggerFactory.getLogger(ValidationLogVisualizer.class);
+
+	private TransformerFactory mFactory = null;
+	private Templates mXsltPDFTemplate = null;
+
+
+	public ValidationLogVisualizer() {
+		mFactory = new net.sf.saxon.TransformerFactoryImpl();
+		// fact = TransformerFactory.newInstance();
+		mFactory.setURIResolver(new ValidationLogVisualizer.ClasspathResourceURIResolver());
+	}
+
+	protected void applyXSLTToPDF(final String xmlContent, final OutputStream PDFOutstream)
+		throws TransformerException {
+		Transformer transformer = mXsltPDFTemplate.newTransformer();
+
+		transformer.transform(new StreamSource(new StringReader(xmlContent)), new StreamResult(PDFOutstream));
+	}
+
+	protected String toFOP(final String xmlContent)
+		throws TransformerException {
+
+		try {
+			if (mXsltPDFTemplate == null) {
+				mXsltPDFTemplate = mFactory.newTemplates(
+					new StreamSource(CLASS_LOADER.getResourceAsStream(RESOURCE_PATH + "stylesheets/result-pdf.xsl")));
+			}
+		} catch (TransformerConfigurationException ex) {
+			LOGGER.error("Failed to init XSLT templates", ex);
+		}
+
+		ByteArrayOutputStream baos = new ByteArrayOutputStream();
+
+		try {
+
+			applyXSLTToPDF(xmlContent, baos);
+
+		} catch (Exception e1) {
+			LOGGER.error("Failed to create PDF", e1);
+		}
+
+		return baos.toString(StandardCharsets.UTF_8);
+	}
+
+	public void toPDF(String xmlLogfileContent, String pdfFilename) {
+
+		// the writing part
+
+		String result = null;
+
+			/* remove file endings so that tests can also pass after checking
+			   out from git with arbitrary options (which may include CSRF changes)
+			 */
+		try {
+			result = this.toFOP(xmlLogfileContent);
+		} catch ( TransformerException e) {
+			LOGGER.error("Failed to apply FOP", e);
+		}
+		DefaultConfigurationBuilder cfgBuilder = new DefaultConfigurationBuilder();
+
+		Configuration cfg = null;
+		try {
+			cfg = cfgBuilder.build(CLASS_LOADER.getResourceAsStream("fop-config.xconf"));
+		} catch (ConfigurationException e) {
+			throw new RuntimeException(e);
+		}
+
+		FopFactoryBuilder builder = new FopFactoryBuilder(new File(".").toURI(), new ClasspathResolverURIAdapter()).setConfiguration(cfg);
+// Step 1: Construct a FopFactory by specifying a reference to the configuration file
+// (reuse if you plan to render multiple documents!)
+
+		FopFactory fopFactory = builder.build();
+
+		fopFactory.getFontManager().setResourceResolver(
+			ResourceResolverFactory.createInternalResourceResolver(
+				new File(".").toURI(),
+				new ClasspathResolverURIAdapter()));
+
+		FOUserAgent userAgent = fopFactory.newFOUserAgent();
+
+		userAgent.getRendererOptions().put("pdf-a-mode", "PDF/A-3b");
+
+// Step 2: Set up output stream.
+// Note: Using BufferedOutputStream for performance reasons (helpful with FileOutputStreams).
+
+		try (OutputStream out = new BufferedOutputStream(new FileOutputStream(pdfFilename))) {
+
+			// Step 3: Construct fop with desired output format
+			Fop fop = fopFactory.newFop(MimeConstants.MIME_PDF, userAgent, out);
+
+			// Step 4: Setup JAXP using identity transformer
+			TransformerFactory factory = TransformerFactory.newInstance();
+			Transformer transformer = factory.newTransformer(); // identity transformer
+
+			// Step 5: Setup input and output for XSLT transformation
+			// Setup input stream
+			Source src = new StreamSource(new ByteArrayInputStream(result.getBytes(StandardCharsets.UTF_8)));
+
+			// Resulting SAX events (the generated FO) must be piped through to FOP
+			Result res = new SAXResult(fop.getDefaultHandler());
+
+			// Step 6: Start XSLT transformation and FOP processing
+			transformer.transform(src, res);
+
+		} catch (FOPException | IOException | TransformerException e) {
+			LOGGER.error("Failed to create PDF", e);
+		}
+	}
+
+	private static class ClasspathResourceURIResolver implements URIResolver {
+		ClasspathResourceURIResolver() {
+			// Do nothing, just prevents synthetic access warning.
+		}
+
+		@Override
+		public Source resolve(String href, String base) throws TransformerException {
+			return new StreamSource(CLASS_LOADER.getResourceAsStream(RESOURCE_PATH + "stylesheets/" + href));
+		}
+	}
+}