1 /**
2 * Copyright 2005-2013 The Kuali Foundation
3 *
4 * Licensed under the Educational Community License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.opensource.org/licenses/ecl2.php
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package org.kuali.rice.krad.theme.preprocessor;
17
18 import org.apache.commons.lang.StringUtils;
19 import org.apache.log4j.Logger;
20 import org.kuali.rice.krad.theme.util.ThemeBuilderConstants;
21 import org.kuali.rice.krad.theme.util.ThemeBuilderUtils;
22 import org.lesscss.LessCompiler;
23 import org.lesscss.LessException;
24 import org.lesscss.LessSource;
25
26 import java.io.File;
27 import java.io.IOException;
28 import java.util.List;
29 import java.util.Properties;
30
31 /**
32 * Pre processor that picks up Less files in the theme directory and compiles to CSS
33 *
34 * <p>
35 * Less files are compiled using the Apache lesscss compiler
36 * </p>
37 *
38 * @author Kuali Rice Team (rice.collab@kuali.org)
39 * @see org.lesscss.LessCompiler
40 */
41 public class LessThemePreProcessor implements ThemePreProcessor {
42 private static final Logger LOG = Logger.getLogger(LessThemePreProcessor.class);
43
44 /**
45 * Processes Less files that should be included for the given theme
46 *
47 * <p>
48 * The list of Less files for the theme is collected by a helper method then iterated over and compiled
49 * using the less compiler. The list of Less files that were processed is written as a property in the theme
50 * properties for direct Less support in development mode
51 * </p>
52 *
53 * @param themeName name of the theme to process
54 * @param themeDirectory directory containing the theme assets
55 * @param themeProperties properties for the theme containing its configuration
56 * @see #getLessFileNamesForTheme(java.lang.String, java.io.File, java.util.Properties, java.io.File)
57 */
58 public void processTheme(String themeName, File themeDirectory, Properties themeProperties) {
59 if (LOG.isDebugEnabled()) {
60 LOG.debug("Performing Less compilation for theme " + themeName);
61 }
62
63 File stylesheetsDirectory = new File(themeDirectory, ThemeBuilderConstants.ThemeDirectories.STYLESHEETS);
64 if (!stylesheetsDirectory.exists()) {
65 throw new RuntimeException("Stylesheets directory does not exist for theme: " + themeName);
66 }
67
68 List<String> lessFileNames = getLessFileNamesForTheme(themeName, themeDirectory, themeProperties,
69 stylesheetsDirectory);
70
71 LessCompiler lessCompiler = new LessCompiler();
72
73 // not compressing here since that will be done later in the build process
74 lessCompiler.setCompress(false);
75
76 for (String lessFileName : lessFileNames) {
77 LOG.info("compiling less file: " + lessFileName);
78
79 File sourceLessFile = new File(stylesheetsDirectory, lessFileName);
80 File compiledLessFile = new File(stylesheetsDirectory, lessFileName.replace(
81 ThemeBuilderConstants.FileExtensions.LESS, ThemeBuilderConstants.FileExtensions.CSS));
82
83 try {
84 LessSource lessSource = new LessSource(sourceLessFile);
85
86 lessCompiler.compile(lessSource, compiledLessFile, true);
87 } catch (IOException e) {
88 throw new RuntimeException("Error while compiling LESS source: " + lessFileName, e);
89 } catch (LessException e) {
90 throw new RuntimeException("Error while compiling LESS source: " + lessFileName, e);
91 }
92 }
93
94 // add list of less files to theme properties so it can be picked up by the view theme
95 // runtime in development mode
96 themeProperties.put(ThemeBuilderConstants.DerivedConfiguration.THEME_LESS_FILES,
97 StringUtils.join(lessFileNames, ","));
98 }
99
100 /**
101 * Builds the list of Less files names that should be processed for the given theme
102 *
103 * <p>
104 * All files with the <code>.less</code> extension that are in the theme's <code>stylesheets</code>
105 * directory are picked up as part of the theme (this includes files that are overlaid from a parent).
106 *
107 * All subdirectories of stylesheets are also picked up, with the exception of the <code>include</code>
108 * subdirectory. Other exclusions can be configured using the <code>lessExcludes</code> property in the
109 * theme's properties file
110 * </p>
111 *
112 * @param themeName name of the theme to pull less files for
113 * @param themeDirectory directory containing the theme's assets
114 * @param themeProperties config properties for the theme
115 * @param stylesheetsDirectory theme directory which contains the stylesheets, less files will be
116 * picked up here
117 * @return list of less file names (any path is relative to the stylesheets directory)
118 */
119 protected List<String> getLessFileNamesForTheme(String themeName, File themeDirectory, Properties themeProperties,
120 File stylesheetsDirectory) {
121 String[] lessIncludes = ThemeBuilderUtils.getPropertyValueAsArray(
122 ThemeBuilderConstants.ThemeConfiguration.LESS_INCLUDES, themeProperties);
123
124 if ((lessIncludes == null) || (lessIncludes.length == 0)) {
125 lessIncludes = new String[1];
126
127 lessIncludes[0] = ThemeBuilderConstants.Patterns.ANT_MATCH_ALL + ThemeBuilderConstants.FileExtensions.LESS;
128 }
129
130 String[] lessExcludes = ThemeBuilderUtils.getPropertyValueAsArray(
131 ThemeBuilderConstants.ThemeConfiguration.LESS_EXCLUDES, themeProperties);
132
133 lessExcludes = ThemeBuilderUtils.addToArray(lessExcludes,
134 ThemeBuilderConstants.ThemeDirectories.INCLUDES + ThemeBuilderConstants.Patterns.ANT_MATCH_DIR);
135
136 return ThemeBuilderUtils.getDirectoryContents(stylesheetsDirectory, lessIncludes, lessExcludes);
137 }
138 }