org.sonar.batch.scan.filesystem.LanguageDetection.java Source code

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Here is the source code for org.sonar.batch.scan.filesystem.LanguageDetection.java

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/*
 * SonarQube
 * Copyright (C) 2009-2016 SonarSource SA
 * mailto:contact AT sonarsource DOT com
 *
 * This program 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 3 of the License, or (at your option) any later version.
 *
 * This program 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.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
package org.sonar.batch.scan.filesystem;

import org.sonar.batch.repository.language.Language;
import org.sonar.batch.repository.language.LanguagesRepository;

import com.google.common.base.Joiner;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.sonar.api.CoreProperties;
import org.sonar.api.batch.fs.InputFile;
import org.sonar.api.batch.fs.internal.PathPattern;
import org.sonar.api.config.Settings;
import org.sonar.api.utils.MessageException;

import javax.annotation.CheckForNull;

import java.text.MessageFormat;
import java.util.List;
import java.util.Map;

/**
 * Detect language of a source file based on its suffix and configured patterns.
 */
class LanguageDetection {

    private static final Logger LOG = LoggerFactory.getLogger(LanguageDetection.class);

    /**
     * Lower-case extension -> languages
     */
    private final Map<String, PathPattern[]> patternsByLanguage = Maps.newLinkedHashMap();
    private final List<String> languagesToConsider = Lists.newArrayList();
    private final String forcedLanguage;

    LanguageDetection(Settings settings, LanguagesRepository languages) {
        for (Language language : languages.all()) {
            String[] filePatterns = settings.getStringArray(getFileLangPatternPropKey(language.key()));
            PathPattern[] pathPatterns = PathPattern.create(filePatterns);
            if (pathPatterns.length > 0) {
                patternsByLanguage.put(language.key(), pathPatterns);
            } else {
                // If no custom language pattern is defined then fallback to suffixes declared by language
                String[] patterns = language.fileSuffixes().toArray(new String[language.fileSuffixes().size()]);
                for (int i = 0; i < patterns.length; i++) {
                    String suffix = patterns[i];
                    String extension = sanitizeExtension(suffix);
                    patterns[i] = new StringBuilder().append("**/*.").append(extension).toString();
                }
                PathPattern[] defaultLanguagePatterns = PathPattern.create(patterns);
                patternsByLanguage.put(language.key(), defaultLanguagePatterns);
                LOG.debug("Declared extensions of language " + language + " were converted to "
                        + getDetails(language.key()));
            }
        }

        forcedLanguage = StringUtils.defaultIfBlank(settings.getString(CoreProperties.PROJECT_LANGUAGE_PROPERTY),
                null);
        // First try with lang patterns
        if (forcedLanguage != null) {
            if (!patternsByLanguage.containsKey(forcedLanguage)) {
                throw MessageException.of("No language is installed with key '" + forcedLanguage
                        + "'. Please update property '" + CoreProperties.PROJECT_LANGUAGE_PROPERTY + "'");
            }
            languagesToConsider.add(forcedLanguage);
        } else {
            languagesToConsider.addAll(patternsByLanguage.keySet());
        }
    }

    Map<String, PathPattern[]> patternsByLanguage() {
        return patternsByLanguage;
    }

    @CheckForNull
    String language(InputFile inputFile) {
        String detectedLanguage = null;
        for (String languageKey : languagesToConsider) {
            if (isCandidateForLanguage(inputFile, languageKey)) {
                if (detectedLanguage == null) {
                    detectedLanguage = languageKey;
                } else {
                    // Language was already forced by another pattern
                    throw MessageException.of(MessageFormat.format(
                            "Language of file ''{0}'' can not be decided as the file matches patterns of both {1} and {2}",
                            inputFile.relativePath(), getDetails(detectedLanguage), getDetails(languageKey)));
                }
            }
        }
        if (detectedLanguage != null) {
            LOG.debug(String.format("Language of file '%s' is detected to be '%s'", inputFile.relativePath(),
                    detectedLanguage));
            return detectedLanguage;
        }

        // Check if deprecated sonar.language is used and we are on a language without declared extensions.
        // Languages without declared suffixes match everything.
        if (forcedLanguage != null && patternsByLanguage.get(forcedLanguage).length == 0) {
            return forcedLanguage;
        }
        return null;
    }

    private boolean isCandidateForLanguage(InputFile inputFile, String languageKey) {
        PathPattern[] patterns = patternsByLanguage.get(languageKey);
        if (patterns != null) {
            for (PathPattern pathPattern : patterns) {
                if (pathPattern.match(inputFile, false)) {
                    return true;
                }
            }
        }
        return false;
    }

    private String getFileLangPatternPropKey(String languageKey) {
        return "sonar.lang.patterns." + languageKey;
    }

    private String getDetails(String detectedLanguage) {
        return getFileLangPatternPropKey(detectedLanguage) + " : "
                + Joiner.on(",").join(patternsByLanguage.get(detectedLanguage));
    }

    static String sanitizeExtension(String suffix) {
        return StringUtils.lowerCase(StringUtils.removeStart(suffix, "."));
    }
}