GroovyConfigurer.java

package com.aperture_software.glados_wiki.config;

import com.google.common.base.Optional;
import com.google.common.base.Strings;
import com.google.common.io.Closer;
import groovy.lang.Binding;
import groovy.lang.GroovyShell;
import groovy.util.ResourceException;
import groovy.util.ScriptException;
import org.apache.commons.configuration.CompositeConfiguration;
import org.apache.commons.configuration.EnvironmentConfiguration;
import org.apache.commons.configuration.JNDIConfiguration;
import org.apache.commons.configuration.SystemConfiguration;
import org.apache.commons.lang3.ObjectUtils;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemManager;
import org.apache.commons.vfs2.VFS;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.naming.NamingException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;

/**
 * Created by jhyun on 14. 1. 12.
 */
public class GroovyConfigurer {

    private static Logger LOG = LoggerFactory.getLogger(GroovyConfigurer.class);
    private WikiConfig wikiConfig;
    private FileSystemManager fsManager = VFS.getManager();

    public GroovyConfigurer() throws Exception {
        runGroovyScript("res:com/aperture_software/glados_wiki/wiki-config.groovy", "DEFAULT-CONFIG");
        //
        Optional<String> userConfigFilename = getUserConfigFilename();
        if (userConfigFilename.isPresent()) {
            runGroovyScript(userConfigFilename.get(), "LOCAL-CONFIG");
        }
    }

    private Optional<String> getUserConfigFilename() throws NamingException {
        CompositeConfiguration cc = new CompositeConfiguration();
        JNDIConfiguration jndi = new JNDIConfiguration();
        EnvironmentConfiguration env = new EnvironmentConfiguration();
        SystemConfiguration jvm = new SystemConfiguration();
        cc.addConfiguration(jvm);
        cc.addConfiguration(env);
        cc.addConfiguration(jndi);
        //
        final String CONFIG_FILENAME = (String) cc.getProperty("gladosWiki_configFile");
        if (false == Strings.isNullOrEmpty(CONFIG_FILENAME)) {
            LOG.debug(String.format("LOCAL-CONFIG CONFIG_FILENAME = %s", CONFIG_FILENAME));
            return Optional.of(CONFIG_FILENAME);
        } else {
            return Optional.absent();
        }
    }

    public WikiConfig getWikiConfig() {
        return wikiConfig;
    }

    public void setWikiConfig(WikiConfig wikiConfig) {
        this.wikiConfig = wikiConfig;
    }

    private WikiConfig runGroovyScript(final String vfsFilename, final String phaseName) throws ResourceException, ScriptException, IOException {
        LOG.debug(String.format("VFS-RESOLVE [%s] ...", vfsFilename));
        FileObject f = fsManager.resolveFile(vfsFilename);
        if (f.exists() == false) {
            LOG.warn(String.format("VFS-FILE NOT FOUND!!! [%s]", vfsFilename));
            //
            return null;
        }
        URL u = f.getURL();
        Closer closer = Closer.create();
        try {
            InputStream in = u.openStream();
            closer.register(in);
            InputStreamReader reader = new InputStreamReader(in);
            closer.register(reader);
            //
            Binding binding = new Binding();
            binding.setVariable("wikiConfig", wikiConfig);
            //
            GroovyShell shell = new GroovyShell(binding);
            shell.evaluate(reader, vfsFilename);
            //
            wikiConfig = (WikiConfig) binding.getVariable("wikiConfig");
            LOG.debug(String.format("WIKI-CONFIG (%s) = %s", phaseName, ObjectUtils.toString(wikiConfig)));
            //
            return wikiConfig;
        } finally {
            closer.close();
        }
    }
}