DbkServlet.java

   1 package org.argeo.publishing.servlet;
   2
   3 import java.io.ByteArrayInputStream;
   4 import java.io.ByteArrayOutputStream;
   5 import java.io.IOException;
   6 import java.io.InputStream;
   7 import java.net.URLDecoder;
   8 import java.nio.charset.StandardCharsets;
   9 import java.nio.file.Files;
  10 import java.nio.file.Paths;
  11 import java.util.Collections;
  12 import java.util.HashMap;
  13 import java.util.Map;
  14
  15 import javax.jcr.Node;
  16 import javax.jcr.Repository;
  17 import javax.jcr.RepositoryException;
  18 import javax.jcr.Session;
  19 import javax.jcr.nodetype.NodeType;
  20 import javax.servlet.ServletException;
  21 import javax.servlet.http.HttpServlet;
  22 import javax.servlet.http.HttpServletRequest;
  23 import javax.servlet.http.HttpServletResponse;
  24 import javax.xml.parsers.DocumentBuilder;
  25 import javax.xml.parsers.DocumentBuilderFactory;
  26 import javax.xml.transform.Result;
  27 import javax.xml.transform.Source;
  28 import javax.xml.transform.Templates;
  29 import javax.xml.transform.Transformer;
  30 import javax.xml.transform.TransformerConfigurationException;
  31 import javax.xml.transform.TransformerFactory;
  32 import javax.xml.transform.dom.DOMSource;
  33 import javax.xml.transform.stream.StreamResult;
  34 import javax.xml.transform.stream.StreamSource;
  35
  36 import org.apache.commons.io.IOUtils;
  37 import org.apache.xalan.processor.TransformerFactoryImpl;
  38 import org.argeo.cms.servlet.ServletAuthUtils;
  39 import org.argeo.cms.ui.CmsTheme;
  40 import org.argeo.docbook.DbkType;
  41 import org.argeo.docbook.DbkUtils;
  42 import org.argeo.jcr.Jcr;
  43 import org.argeo.jcr.JcrException;
  44 import org.argeo.jcr.JcrUtils;
  45 import org.w3c.dom.Document;
  46
  47 /**
  48  * A servlet transforming a dbk:* JCR node into HTML, using the DocBook XSL.
  49  */
  50 public class DbkServlet extends HttpServlet {
  51         private static final long serialVersionUID = 6906020513498289335L;
  52
  53         private Repository repository;
  54
  55         private DocumentBuilderFactory documentBuilderFactory;
  56         private TransformerFactory transformerFactory;
  57         private Templates docBoookTemplates;
  58
  59         private Map<String, CmsTheme> themes = Collections.synchronizedMap(new HashMap<>());
  60
  61         @Override
  62         protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  63
  64                 String pathInfo = req.getPathInfo();
  65                 if (pathInfo.startsWith("//"))
  66                         pathInfo = pathInfo.substring(1);
  67                 String path = URLDecoder.decode(pathInfo, StandardCharsets.UTF_8);
  68
  69                 if (path.toLowerCase().endsWith(".css")) {
  70                         path = path.substring(1);
  71                         int firstSlash = path.indexOf('/');
  72                         String themeId = path.substring(0, firstSlash);
  73                         String cssPath = path.substring(firstSlash);
  74                         CmsTheme cmsTheme = themes.get(themeId);
  75                         if (cmsTheme == null)
  76                                 throw new IllegalArgumentException("Theme " + themeId + " not found.");
  77                         resp.setContentType("text/css");
  78                         IOUtils.copy(cmsTheme.getResourceAsStream(cssPath), resp.getOutputStream());
  79                         return;
  80                 }
  81
  82                 Session session = null;
  83                 try {
  84                         session = ServletAuthUtils.doAs(() -> Jcr.login(repository, null), req);
  85                         Node documentNode = session.getNode(path);
  86                         Node node;
  87                         if (documentNode.hasNode(DbkType.article.get()))
  88                                 node = documentNode.getNode(DbkType.article.get());
  89                         else {
  90                                 throw new IllegalArgumentException("Unsupported node " + documentNode);
  91                         }
  92                         if (DbkUtils.isDbk(node)) {
  93                                 CmsTheme cmsTheme = null;
  94                                 String themeId = req.getParameter("themeId");
  95                                 if (themeId != null) {
  96                                         cmsTheme = themes.get(themeId);
  97                                         if (cmsTheme == null)
  98                                                 throw new IllegalArgumentException("Theme " + themeId + " not found.");
  99                                 }
 100
 101                                 // TODO customise DocBook so that it outputs UTF-8
 102                                 // see http://www.sagehill.net/docbookxsl/OutputEncoding.html
 103                                 resp.setContentType("text/html; charset=ISO-8859-1");
 104
 105                                 // TODO optimise with pipes, SAX, etc. ?
 106                                 byte[] arr;
 107                                 try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
 108                                         session.exportDocumentView(node.getPath(), out, true, false);
 109                                         arr = out.toByteArray();
 110 //                              System.out.println(new String(arr, StandardCharsets.UTF_8));
 111                                 } catch (RepositoryException e) {
 112                                         throw new JcrException(e);
 113                                 }
 114
 115                                 try (InputStream in = new ByteArrayInputStream(arr);
 116 //                                      ByteArrayOutputStream out = new ByteArrayOutputStream();
 117                                 ) {
 118
 119                                         Result xmlOutput = new StreamResult(resp.getOutputStream());
 120
 121                                         DocumentBuilder docBuilder = documentBuilderFactory.newDocumentBuilder();
 122 //                              Document doc = docBuilder.parse(new File(
 123 //                                              System.getProperty("user.home") + "/dev/git/gpl/argeo-qa/doc/platform/argeo-platform.dbk.xml"));
 124                                         Document doc = docBuilder.parse(in);
 125                                         Source xmlInput = new DOMSource(doc);
 126
 127                                         Transformer transformer = docBoookTemplates.newTransformer();
 128
 129                                         // gather CSS
 130                                         if (cmsTheme != null) {
 131                                                 StringBuilder sb = new StringBuilder();
 132                                                 for (String cssPath : cmsTheme.getWebCssPaths()) {
 133                                                         sb.append(req.getContextPath()).append(req.getServletPath()).append('/');
 134                                                         sb.append(themeId).append('/').append(cssPath).append(' ');
 135                                                 }
 136                                                 sb.append("https://fonts.googleapis.com/css2?family=Roboto:wght@400;700&display=swap")
 137                                                                 .append(' ');
 138                                                 sb.append(
 139                                                                 "https://fonts.googleapis.com/css2?family=Montserrat:ital,wght@0,300;0,400;0,600;1,400&display=swap")
 140                                                                 .append(' ');
 141                                                 if (sb.length() > 0)
 142                                                         transformer.setParameter("html.stylesheet", sb.toString());
 143                                         }
 144                                         transformer.transform(xmlInput, xmlOutput);
 145 //                              resp.getOutputStream().write(out.toByteArray());
 146                                 } catch (Exception e) {
 147                                         throw new ServletException("Cannot transform " + path, e);
 148                                 }
 149                         } else if (node.isNodeType(NodeType.NT_FILE)) {// media download etc.
 150                                 String fileNameLowerCase = node.getName().toLowerCase();
 151                                 if (fileNameLowerCase.endsWith(".jpg") || fileNameLowerCase.endsWith(".jpeg")) {
 152                                         resp.setContentType("image/jpeg");
 153                                 } else if (fileNameLowerCase.endsWith(".png")) {
 154                                         resp.setContentType("image/png");
 155                                 } else if (fileNameLowerCase.endsWith(".gif")) {
 156                                         resp.setContentType("image/gif");
 157                                 } else if (fileNameLowerCase.endsWith(".svg")) {
 158                                         resp.setContentType("image/svg+xml");
 159                                 } else {
 160                                         // TODO know more content types...
 161                                         resp.setHeader("Content-Disposition", "attachment; filename=\"" + node.getName() + "\"");
 162                                 }
 163                                 IOUtils.copy(JcrUtils.getFileAsStream(node), resp.getOutputStream());
 164                         } else {
 165                                 throw new IllegalArgumentException("Unsupported node " + node);
 166                         }
 167                 } catch (RepositoryException e1) {
 168                         throw new JcrException(e1);
 169                 } finally {
 170                         Jcr.logout(session);
 171                 }
 172         }
 173
 174         @Override
 175         public void init() throws ServletException {
 176
 177                 // TODO improve configuration and provisioning of DocBook XSL
 178                 String xslBase = System.getProperty("argeo.docbook.xsl");
 179                 if (xslBase == null) {
 180                         String defaultXslBase = "/opt/docbook-xsl";
 181                         if (!Files.exists(Paths.get(defaultXslBase))) {
 182                                 throw new ServletException("System property argeo.docbook.xsl is not set and default location "
 183                                                 + defaultXslBase + " does not exist.");
 184                         } else {
 185                                 xslBase = defaultXslBase;
 186                         }
 187                 }
 188                 String xsl = xslBase + "/html/docbook.xsl";
 189
 190                 documentBuilderFactory = DocumentBuilderFactory.newInstance();
 191                 documentBuilderFactory.setXIncludeAware(true);
 192                 documentBuilderFactory.setNamespaceAware(true);
 193
 194                 // We must explicitly use the non-XSLTC transformer, as XSLTC is not working
 195                 // with DocBook stylesheets
 196                 transformerFactory = new TransformerFactoryImpl();
 197
 198                 Source xslSource = new StreamSource(xsl);
 199                 try {
 200                         docBoookTemplates = transformerFactory.newTemplates(xslSource);
 201                         if (docBoookTemplates == null)
 202                                 throw new ServletException("Could not instantiate XSL " + xsl);
 203                 } catch (TransformerConfigurationException e) {
 204                         throw new ServletException("Cannot instantiate XSL " + xsl, e);
 205                 }
 206         }
 207
 208         public void setRepository(Repository repository) {
 209                 this.repository = repository;
 210         }
 211
 212         public void addTheme(CmsTheme theme, Map<String, String> properties) {
 213                 themes.put(theme.getThemeId(), theme);
 214         }
 215
 216         public void removeTheme(CmsTheme theme, Map<String, String> properties) {
 217                 themes.remove(theme.getThemeId());
 218         }
 219
 220 }