/**

* Jooby https://jooby.io

* Apache License Version 2.0 https://jooby.io/LICENSE.txt

* Copyright 2014 Edgar Espina

*/

package io.jooby;

import javax.annotation.Nonnull;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.util.ArrayList;

import java.util.LinkedHashMap;

import java.util.List;

import java.util.Map;

import java.util.Optional;

/**

* Utility class that initializes logback or log4j2 logging implementation.

*

* Initializes the <code>logback.configurationFile</code> system property when a

* <code>logback[.env].xml</code> file is found at <code>user.dir/conf</code> directory or

* <code>user.dir</code>.

*

* Initializes the <code>log4j.configurationFile</code> system property when a

* <code>log4j[.env].[ext]</code> file is found at <code>user.dir/conf</code> directory or

* <code>user.dir</code>. Extension can be one of: <code>.xml</code>, <code>.properties</code>,

* <code>.yaml</code> or <code>.json</code>.

*

* NOTE: This class must be call it before instantiating a logger instance. Otherwise, this setup

* is completely ignored.

*

* @since 2.0.0

* @author edgar

*/

public final class LogConfigurer {

private LogConfigurer() {

}

/**

* Initializes the <code>logback.configurationFile</code> system property when a

* <code>logback[.env].xml</code> file is found at <code>user.dir/conf</code> directory or

* <code>user.dir</code>.

*

* Initializes the <code>log4j.configurationFile</code> system property when a

* <code>log4j[.env].[ext]</code> file is found at <code>user.dir/conf</code> directory or

* <code>user.dir</code>. Extension can be one of: <code>.xml</code>, <code>.properties</code>,

* <code>.yaml</code> or <code>.json</code>.

*

* @param names Actives environment names. Useful for choosing an environment specific logging

* configuration file.

*/

public static void configure(@Nonnull List<String> names) {

String[] keys = {"logback.configurationFile", "log4j.configurationFile"};

for (String key : keys) {

String file = property(key);

if (file != null) {

// found, reset and exit

System.setProperty(key, file);

return;

}

}

Path userdir = Paths.get(System.getProperty("user.dir"));

Map<String, List<Path>> options = new LinkedHashMap<>();

options.put("logback.configurationFile", logbackFiles(userdir, names));

options.put("log4j.configurationFile", log4jFiles(userdir, names));

for (Map.Entry<String, List<Path>> entry : options.entrySet()) {

Optional<Path> logfile = entry.getValue().stream().filter(Files::exists)

.findFirst()

.map(Path::toAbsolutePath);

if (logfile.isPresent()) {

System.setProperty(entry.getKey(), logfile.get().toString());

break;

}

}

}

private static List<Path> logbackFiles(Path basedir, List<String> env) {

return logFile(basedir, env, "logback", ".xml");

}

private static List<Path> logFile(Path basedir, List<String> names, String name, String ext) {

Path confdir = basedir.resolve("conf");

List<Path> result = new ArrayList<>();

for (String env : names) {

String envlogfile = name + "." + env + ext;

result.add(confdir.resolve(envlogfile));

result.add(basedir.resolve(envlogfile));

}

String logfile = name + ext;

result.add(confdir.resolve(logfile));

result.add(basedir.resolve(logfile));

return result;

}

private static List<Path> log4jFiles(Path basedir, List<String> names) {

List<Path> result = new ArrayList<>();

String[] extensions = {".properties", ".xml", ".yaml", ".yml", ".json"};

for (String extension : extensions) {

result.addAll(logFile(basedir, names, "log4j", extension));

result.addAll(logFile(basedir, names, "log4j2", extension));

}

return result;

}

private static String property(String name) {

return System.getProperty(name, System.getenv(name));

}

}