doxia-modules/doxia-module-markdown/src/main/java/org/apache/maven/doxia/module/markdown/MarkdownParser.java - maven-doxia - Git at Google

 package org.apache.maven.doxia.module.markdown;

 /*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
  * regarding copyright ownership.  The ASF licenses this file
  * to you under the Apache License, Version 2.0 (the
  * "License"); you may not use this file except in compliance
  * with the License.  You may obtain a copy of the License at
  *
  *   http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing,
  * software distributed under the License is distributed on an
  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  * KIND, either express or implied.  See the License for the
  * specific language governing permissions and limitations
  * under the License.
  */

 import org.apache.commons.lang.StringEscapeUtils;
 import org.apache.commons.lang.StringUtils;
 import org.apache.maven.doxia.module.xhtml.XhtmlParser;
 import org.apache.maven.doxia.parser.ParseException;
 import org.apache.maven.doxia.parser.Parser;
 import org.apache.maven.doxia.sink.Sink;
 import org.codehaus.plexus.component.annotations.Component;
 import org.codehaus.plexus.util.IOUtil;
 import org.pegdown.Extensions;
 import org.pegdown.PegDownProcessor;
 import org.pegdown.ast.HeaderNode;
 import org.pegdown.ast.Node;
 import org.pegdown.ast.RootNode;
 import org.pegdown.ast.SuperNode;
 import org.pegdown.ast.TextNode;

 import java.io.IOException;
 import java.io.Reader;
 import java.io.StringReader;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;

 /**
  * Implementation of {@link org.apache.maven.doxia.parser.Parser} for Markdown documents.
  * <p/>
  * Defers parsing to the <a href="http://pegdown.org">PegDown library</a>.
  *
  * @author Julien Nicoulaud <julien.nicoulaud@gmail.com>
  * @since 1.3
  */
 @Component( role = Parser.class, hint = "markdown" )
 public class MarkdownParser
     extends XhtmlParser
 {

     /**
      * The role hint for the {@link MarkdownParser} Plexus component.
      */
     public static final String ROLE_HINT = "markdown";

     /**
      * The {@link PegDownProcessor} used to convert Pegdown documents to HTML.
      */
     protected static final PegDownProcessor PEGDOWN_PROCESSOR =
         new PegDownProcessor( Extensions.ALL & ~Extensions.HARDWRAPS, Long.MAX_VALUE );

     /**
      * Regex that identifies a multimarkdown-style metadata section at the start of the document
      */
     private static final String MULTI_MARKDOWN_METADATA_SECTION =
         "^(((?:[^\\s:][^:]*):(?:.*(?:\r?\n\\s[^\\s].*)*\r?\n))+)(?:\\s*\r?\n)";

     /**
      * Regex that captures the key and value of a multimarkdown-style metadata entry.
      */
     private static final String MULTI_MARKDOWN_METADATA_ENTRY = "([^\\s:][^:]*):(.*(?:\r?\n\\s[^\\s].*)*)\r?\n";

     /**
      * In order to ensure that we have minimal risk of false positives when slurping metadata sections, the
      * first key in the metadata section must be one of these standard keys or else the entire metadata section is
      * ignored.
      */
     private static final String[] STANDARD_METADATA_KEYS =
         { "title", "author", "date", "address", "affiliation", "copyright", "email", "keywords", "language", "phone",
             "subtitle" };


     /**
      * {@inheritDoc}
      */
     @Override
     public void parse( Reader source, Sink sink )
         throws ParseException
     {
         try
         {
             String text = IOUtil.toString( source );
             StringBuilder html = new StringBuilder( text.length() * 2 );
             html.append( "<html>" );
             html.append( "<head>" );
             Pattern metadataPattern = Pattern.compile( MULTI_MARKDOWN_METADATA_SECTION, Pattern.MULTILINE );
             Matcher metadataMatcher = metadataPattern.matcher( text );
             boolean haveTitle = false;
             if ( metadataMatcher.find() )
             {
                 metadataPattern = Pattern.compile( MULTI_MARKDOWN_METADATA_ENTRY, Pattern.MULTILINE );
                 Matcher lineMatcher = metadataPattern.matcher( metadataMatcher.group( 1 ) );
                 boolean first = true;
                 while ( lineMatcher.find() )
                 {
                     String key = StringUtils.trimToEmpty( lineMatcher.group( 1 ) );
                     if ( first )
                     {
                         boolean found = false;
                         for ( String k : STANDARD_METADATA_KEYS )
                         {
                             if ( k.equalsIgnoreCase( key ) )
                             {
                                 found = true;
                                 break;
                             }
                         }
                         if ( !found )
                         {
                             break;
                         }
                         first = false;
                     }
                     String value = StringUtils.trimToEmpty( lineMatcher.group( 2 ) );
                     if ( "title".equalsIgnoreCase( key ) )
                     {
                         haveTitle = true;
                         html.append( "<title>" );
                         html.append( StringEscapeUtils.escapeXml( value ) );
                         html.append( "</title>" );
                     }
                     else if ( "author".equalsIgnoreCase( key ) )
                     {
                         html.append( "<meta name=\'author\' content=\'" );
                         html.append( StringEscapeUtils.escapeXml( value ) );
                         html.append( "\' />" );
                     }
                     else if ( "date".equalsIgnoreCase( key ) )
                     {
                         html.append( "<meta name=\'date\' content=\'" );
                         html.append( StringEscapeUtils.escapeXml( value ) );
                         html.append( "\' />" );
                     }
                     else
                     {
                         html.append( "<meta name=\'" );
                         html.append( StringEscapeUtils.escapeXml( key ) );
                         html.append( "\' content=\'" );
                         html.append( StringEscapeUtils.escapeXml( value ) );
                         html.append( "\' />" );
                     }
                 }
                 if ( !first )
                 {
                     text = text.substring( metadataMatcher.end() );
                 }
             }
             RootNode rootNode = PEGDOWN_PROCESSOR.parseMarkdown( text.toCharArray() );
             if ( !haveTitle && rootNode.getChildren().size() > 0 )
             {
                 // use the first node only if it is a heading
                 final Node firstNode = rootNode.getChildren().get( 0 );
                 if ( firstNode instanceof HeaderNode )
                 {
                     html.append( "<title>" );
                     html.append( StringEscapeUtils.escapeXml( nodeText( firstNode ) ) );
                     html.append( "</title>" );
                 }
             }
             html.append( "</head>" );
             html.append( "<body>" );
             html.append( new MarkdownToDoxiaHtmlSerializer().toHtml( rootNode ) );
             html.append( "</body>" );
             html.append( "</html>" );
             super.parse( new StringReader( html.toString() ), sink );
         }
         catch ( IOException e )
         {
             throw new ParseException( "Failed reading Markdown source document", e );
         }
     }

     public static String nodeText( Node node )
     {
         StringBuilder builder = new StringBuilder();
         if ( node instanceof TextNode )
         {
             builder.append( TextNode.class.cast( node ).getText() );
         }
         else
         {
             for ( Node n : node.getChildren() )
             {
                 if ( n instanceof TextNode )
                 {
                     builder.append( TextNode.class.cast( n ).getText() );
                 }
                 else if ( n instanceof SuperNode )
                 {
                     builder.append( nodeText( n ) );
                 }
             }
         }
         return builder.toString();
     }

 }
	package org.apache.maven.doxia.module.markdown;

	/*
	* Licensed to the Apache Software Foundation (ASF) under one
	* or more contributor license agreements. See the NOTICE file
	* distributed with this work for additional information
	* regarding copyright ownership. The ASF licenses this file
	* to you under the Apache License, Version 2.0 (the
	* "License"); you may not use this file except in compliance
	* with the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing,
	* software distributed under the License is distributed on an
	* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	* KIND, either express or implied. See the License for the
	* specific language governing permissions and limitations
	* under the License.
	*/

	import org.apache.commons.lang.StringEscapeUtils;
	import org.apache.commons.lang.StringUtils;
	import org.apache.maven.doxia.module.xhtml.XhtmlParser;
	import org.apache.maven.doxia.parser.ParseException;
	import org.apache.maven.doxia.parser.Parser;
	import org.apache.maven.doxia.sink.Sink;
	import org.codehaus.plexus.component.annotations.Component;
	import org.codehaus.plexus.util.IOUtil;
	import org.pegdown.Extensions;
	import org.pegdown.PegDownProcessor;
	import org.pegdown.ast.HeaderNode;
	import org.pegdown.ast.Node;
	import org.pegdown.ast.RootNode;
	import org.pegdown.ast.SuperNode;
	import org.pegdown.ast.TextNode;

	import java.io.IOException;
	import java.io.Reader;
	import java.io.StringReader;
	import java.util.regex.Matcher;
	import java.util.regex.Pattern;

	/**
	* Implementation of {@link org.apache.maven.doxia.parser.Parser} for Markdown documents.
	* <p/>
	* Defers parsing to the <a href="http://pegdown.org">PegDown library</a>.
	*
	* @author Julien Nicoulaud <julien.nicoulaud@gmail.com>
	* @since 1.3
	*/
	@Component( role = Parser.class, hint = "markdown" )
	public class MarkdownParser
	extends XhtmlParser
	{

	/**
	* The role hint for the {@link MarkdownParser} Plexus component.
	*/
	public static final String ROLE_HINT = "markdown";

	/**
	* The {@link PegDownProcessor} used to convert Pegdown documents to HTML.
	*/
	protected static final PegDownProcessor PEGDOWN_PROCESSOR =
	new PegDownProcessor( Extensions.ALL & ~Extensions.HARDWRAPS, Long.MAX_VALUE );

	/**
	* Regex that identifies a multimarkdown-style metadata section at the start of the document
	*/
	private static final String MULTI_MARKDOWN_METADATA_SECTION =
	"^(((?:[^\\s:][^:]):(?:.(?:\r?\n\\s[^\\s].)\r?\n))+)(?:\\s*\r?\n)";

	/**
	* Regex that captures the key and value of a multimarkdown-style metadata entry.
	*/
	private static final String MULTI_MARKDOWN_METADATA_ENTRY = "([^\\s:][^:]):(.(?:\r?\n\\s[^\\s].))\r?\n";

	/**
	* In order to ensure that we have minimal risk of false positives when slurping metadata sections, the
	* first key in the metadata section must be one of these standard keys or else the entire metadata section is
	* ignored.
	*/
	private static final String[] STANDARD_METADATA_KEYS =
	{ "title", "author", "date", "address", "affiliation", "copyright", "email", "keywords", "language", "phone",
	"subtitle" };


	/**
	* {@inheritDoc}
	*/
	@Override
	public void parse( Reader source, Sink sink )
	throws ParseException
	{
	try
	{
	String text = IOUtil.toString( source );
	StringBuilder html = new StringBuilder( text.length() * 2 );
	html.append( "<html>" );
	html.append( "<head>" );
	Pattern metadataPattern = Pattern.compile( MULTI_MARKDOWN_METADATA_SECTION, Pattern.MULTILINE );
	Matcher metadataMatcher = metadataPattern.matcher( text );
	boolean haveTitle = false;
	if ( metadataMatcher.find() )
	{
	metadataPattern = Pattern.compile( MULTI_MARKDOWN_METADATA_ENTRY, Pattern.MULTILINE );
	Matcher lineMatcher = metadataPattern.matcher( metadataMatcher.group( 1 ) );
	boolean first = true;
	while ( lineMatcher.find() )
	{
	String key = StringUtils.trimToEmpty( lineMatcher.group( 1 ) );
	if ( first )
	{
	boolean found = false;
	for ( String k : STANDARD_METADATA_KEYS )
	{
	if ( k.equalsIgnoreCase( key ) )
	{
	found = true;
	break;
	}
	}
	if ( !found )
	{
	break;
	}
	first = false;
	}
	String value = StringUtils.trimToEmpty( lineMatcher.group( 2 ) );
	if ( "title".equalsIgnoreCase( key ) )
	{
	haveTitle = true;
	html.append( "<title>" );
	html.append( StringEscapeUtils.escapeXml( value ) );
	html.append( "</title>" );
	}
	else if ( "author".equalsIgnoreCase( key ) )
	{
	html.append( "<meta name=\'author\' content=\'" );
	html.append( StringEscapeUtils.escapeXml( value ) );
	html.append( "\' />" );
	}
	else if ( "date".equalsIgnoreCase( key ) )
	{
	html.append( "<meta name=\'date\' content=\'" );
	html.append( StringEscapeUtils.escapeXml( value ) );
	html.append( "\' />" );
	}
	else
	{
	html.append( "<meta name=\'" );
	html.append( StringEscapeUtils.escapeXml( key ) );
	html.append( "\' content=\'" );
	html.append( StringEscapeUtils.escapeXml( value ) );
	html.append( "\' />" );
	}
	}
	if ( !first )
	{
	text = text.substring( metadataMatcher.end() );
	}
	}
	RootNode rootNode = PEGDOWN_PROCESSOR.parseMarkdown( text.toCharArray() );
	if ( !haveTitle && rootNode.getChildren().size() > 0 )
	{
	// use the first node only if it is a heading
	final Node firstNode = rootNode.getChildren().get( 0 );
	if ( firstNode instanceof HeaderNode )
	{
	html.append( "<title>" );
	html.append( StringEscapeUtils.escapeXml( nodeText( firstNode ) ) );
	html.append( "</title>" );
	}
	}
	html.append( "</head>" );
	html.append( "<body>" );
	html.append( new MarkdownToDoxiaHtmlSerializer().toHtml( rootNode ) );
	html.append( "</body>" );
	html.append( "</html>" );
	super.parse( new StringReader( html.toString() ), sink );
	}
	catch ( IOException e )
	{
	throw new ParseException( "Failed reading Markdown source document", e );
	}
	}

	public static String nodeText( Node node )
	{
	StringBuilder builder = new StringBuilder();
	if ( node instanceof TextNode )
	{
	builder.append( TextNode.class.cast( node ).getText() );
	}
	else
	{
	for ( Node n : node.getChildren() )
	{
	if ( n instanceof TextNode )
	{
	builder.append( TextNode.class.cast( n ).getText() );
	}
	else if ( n instanceof SuperNode )
	{
	builder.append( nodeText( n ) );
	}
	}
	}
	return builder.toString();
	}

	}