Java tutorial
/** * Copyright (c) 2000-present Liferay, Inc. All rights reserved. * * This library is free software; you can redistribute it and/or modify it under * the terms of the GNU Lesser General Public License as published by the Free * Software Foundation; either version 2.1 of the License, or (at your option) * any later version. * * This library is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more * details. */ package com.liferay.knowledgebase.admin.importer.util; import com.liferay.knowledgebase.KBArticleImportException; import com.liferay.knowledgebase.model.KBArticle; import com.liferay.markdown.converter.MarkdownConverter; import com.liferay.markdown.converter.factory.MarkdownConverterFactoryUtil; import com.liferay.portal.kernel.exception.PortalException; import com.liferay.portal.kernel.log.Log; import com.liferay.portal.kernel.log.LogFactoryUtil; import com.liferay.portal.kernel.repository.model.FileEntry; import com.liferay.portal.kernel.util.CharPool; import com.liferay.portal.kernel.util.HtmlUtil; import com.liferay.portal.kernel.util.StringBundler; import com.liferay.portal.kernel.util.StringPool; import com.liferay.portal.kernel.util.StringUtil; import com.liferay.portal.kernel.util.Validator; import com.liferay.portal.kernel.zip.ZipReader; import com.liferay.portlet.documentlibrary.util.DLUtil; import java.io.IOException; import java.util.Map; import java.util.Set; import java.util.TreeSet; /** * @author Sergio Gonzlez */ public class KBArticleMarkdownConverter { public KBArticleMarkdownConverter(String markdown, String fileEntryName, Map<String, String> metadata) throws KBArticleImportException { MarkdownConverter markdownConverter = MarkdownConverterFactoryUtil.create(); String html = null; try { html = markdownConverter.convert(markdown); } catch (IOException ioe) { throw new KBArticleImportException("Unable to convert Markdown to HTML: " + ioe.getLocalizedMessage(), ioe); } String heading = getHeading(html); if (Validator.isNull(heading)) { throw new KBArticleImportException("Unable to extract heading from converted HTML: " + html); } _urlTitle = getUrlTitle(heading); _title = HtmlUtil.unescape(stripIds(heading)); html = stripIds(html); _html = stripHeading(html); String baseSourceURL = metadata.get(_METADATA_BASE_SOURCE_URL); _sourceURL = buildSourceURL(baseSourceURL, fileEntryName); } public String getSourceURL() { return _sourceURL; } public String getTitle() { return _title; } public String getUrlTitle() { return _urlTitle; } public String processAttachmentsReferences(long userId, KBArticle kbArticle, ZipReader zipReader, Map<String, FileEntry> fileEntriesMap) throws PortalException { Set<Integer> indexes = new TreeSet<Integer>(); int index = 0; while ((index = _html.indexOf("<img", index)) > -1) { indexes.add(index); index += 4; } if (indexes.isEmpty()) { return _html; } StringBundler sb = new StringBundler(); int previousIndex = 0; for (int curIndex : indexes) { if (curIndex < 0) { break; } if (curIndex > previousIndex) { // Append text from previous position up to image tag String text = _html.substring(previousIndex, curIndex); sb.append(text); } int pos = _html.indexOf("/>", curIndex); if (pos < 0) { if (_log.isDebugEnabled()) { _log.debug("Expected close tag for image " + _html.substring(curIndex)); } sb.append(_html.substring(curIndex)); previousIndex = curIndex; break; } String text = _html.substring(curIndex, pos); String imageFileName = KBArticleImporterUtil.extractImageFileName(text); FileEntry imageFileEntry = KBArticleImporterUtil.addImageFileEntry(imageFileName, userId, kbArticle, zipReader, fileEntriesMap); if (imageFileEntry == null) { if (_log.isWarnEnabled()) { _log.warn("Unable to find image source " + text); } sb.append("<img alt=\"missing image\" src=\"\" "); } else { String imageSrc = StringPool.BLANK; try { imageSrc = DLUtil.getPreviewURL(imageFileEntry, imageFileEntry.getFileVersion(), null, StringPool.BLANK); } catch (PortalException pe) { if (_log.isWarnEnabled()) { _log.warn("Unable to obtain image URL from file entry " + imageFileEntry.getFileEntryId()); } } sb.append("<img alt=\""); sb.append(HtmlUtil.escapeAttribute(imageFileEntry.getTitle())); sb.append("\" src=\""); sb.append(imageSrc); sb.append("\" "); } previousIndex = pos; } if (previousIndex < _html.length()) { sb.append(_html.substring(previousIndex)); } return sb.toString(); } protected String buildSourceURL(String baseSourceURL, String fileEntryName) { if (!Validator.isUrl(baseSourceURL)) { return null; } int pos = baseSourceURL.length() - 1; while (pos >= 0) { char c = baseSourceURL.charAt(pos); if (c != CharPool.SLASH) { break; } pos--; } StringBundler sb = new StringBundler(3); sb.append(baseSourceURL.substring(0, pos + 1)); if (!fileEntryName.startsWith(StringPool.SLASH)) { sb.append(StringPool.SLASH); } sb.append(fileEntryName); return sb.toString(); } protected String getHeading(String html) { int x = html.indexOf("<h1>"); int y = html.indexOf("</h1>"); if ((x == -1) || (y == -1) || (x > y)) { return null; } return html.substring(x + 4, y); } protected String getUrlTitle(String heading) { String urlTitle = null; int x = heading.indexOf("[](id="); int y = heading.indexOf(StringPool.CLOSE_PARENTHESIS, x); if (y > (x + 1)) { int equalsSign = heading.indexOf(StringPool.EQUAL, x); urlTitle = heading.substring(equalsSign + 1, y); urlTitle = StringUtil.replace(urlTitle, StringPool.SPACE, StringPool.DASH); urlTitle = StringUtil.toLowerCase(urlTitle); } if (!urlTitle.startsWith(StringPool.SLASH)) { urlTitle = StringPool.SLASH + urlTitle; } return urlTitle; } protected String stripHeading(String html) { int index = html.indexOf("</h1>"); if (index == -1) { return html; } return html.substring(index + 5); } protected String stripIds(String content) { int index = content.indexOf("[](id="); if (index == -1) { return content; } StringBundler sb = new StringBundler(); do { int x = content.indexOf(StringPool.EQUAL, index); int y = content.indexOf(StringPool.CLOSE_PARENTHESIS, x); if (y != -1) { sb.append(StringUtil.trimTrailing(content.substring(0, index))); content = content.substring(y + 1); } else { if (_log.isWarnEnabled()) { String msg = content.substring(index); // Get the invalid id text from the content int spaceIndex = content.indexOf(StringPool.SPACE); if (spaceIndex != -1) { msg = content.substring(index, spaceIndex); } _log.warn("Missing ')' for web content containing header id " + msg); } // Since no close parenthesis remains in the content, stop // stripping out IDs and simply include all of the remaining // content break; } } while ((index = content.indexOf("[](id=")) != -1); sb.append(content); return sb.toString(); } private static final String _METADATA_BASE_SOURCE_URL = "base.source.url"; private static Log _log = LogFactoryUtil.getLog(KBArticleMarkdownConverter.class); private String _html; private String _sourceURL; private String _title; private String _urlTitle; }