[logback-dev] [JIRA] Commented: (LBCORE-171) Can't use logback on GAE SDK 1.3.7 when configured with logback.xml

13 Oct 2010

      [ http://jira.qos.ch/browse/LBCORE-171?page=com.atlassian.jira.plugin.system.i... ] 

Maxim Veksler commented on LBCORE-171:
--------------------------------------

Work around, based on the following thread http://www.mail-archive.com/google-appengine-java@googlegroups.com/msg12031....

Create in your project the following class (taken from version 0.9.24 of logback):

===

/**
 * Logback: the reliable, generic, fast and flexible logging framework.
 * Copyright (C) 1999-2010, QOS.ch. All rights reserved.
 *
 * This program and the accompanying materials are dual-licensed under either
 * the terms of the Eclipse Public License v1.0 as published by the Eclipse
 * Foundation
 *
 * or (per the licensee's choosing)
 *
 * under the terms of the GNU Lesser General Public License version 2.1 as
 * published by the Free Software Foundation.
 */
package ch.qos.logback.core.util;

import java.net.InetAddress;
import java.net.UnknownHostException;

import com.google.appengine.api.utils.SystemProperty;

import ch.qos.logback.core.Context;
import ch.qos.logback.core.CoreConstants;
import ch.qos.logback.core.spi.ContextAwareBase;

public class ContextUtil extends ContextAwareBase {

  public ContextUtil(Context context) {
    setContext(context);
  }

  static String getLocalHostName() throws UnknownHostException {
	  return SystemProperty.applicationId.get();
  }

  /**
   * Add the local host's name as a property
   */
  public void addHostNameAsProperty() {
    try {
      String localhostName =  getLocalHostName();
      context.putProperty(CoreConstants.HOSTNAME_KEY, localhostName);
    } catch (UnknownHostException e) {
      addError("Failed to get local hostname", e);
    } catch (SecurityException e) {
      addError("Failed to get local hostname", e);
    }
  }
}

===
...
Can't use logback on GAE SDK 1.3.7 when configured with logback.xml
-------------------------------------------------------------------
Key: LBCORE-171
                URL: http://jira.qos.ch/browse/LBCORE-171
            Project: logback-core
         Issue Type: Bug
   Affects Versions: 0.9.24
        Environment: GAE/J 1.3.7
           Reporter: Maxim Veksler
           Assignee: Logback dev list
Trying to initialize logback with custom configuration file (logback.xml) running on GAE platform throws the following exception
Failed to instantiate [ch.qos.logback.classic.LoggerContext]
Reported exception:
java.lang.NoClassDefFoundError: java.net.InetAddress is a restricted class. Please see the Google  App Engine developer's guide for more details.
  at com.google.appengine.tools.development.agent.runtime.Runtime.reject(Runtime.java:51)
  at ch.qos.logback.core.util.ContextUtil.getLocalHostName(ContextUtil.java:30)
  at ch.qos.logback.core.util.ContextUtil.addHostNameAsProperty(ContextUtil.java:39)
  at ch.qos.logback.classic.joran.action.ConfigurationAction.begin(ConfigurationAction.java:47)
  at ch.qos.logback.core.joran.spi.Interpreter.callBeginAction(Interpreter.java:273)
  at ch.qos.logback.core.joran.spi.Interpreter.startElement(Interpreter.java:145)
  at ch.qos.logback.core.joran.spi.Interpreter.startElement(Interpreter.java:127)
  at ch.qos.logback.core.joran.spi.EventPlayer.play(EventPlayer.java:40)
  at ch.qos.logback.core.joran.spi.Interpreter.play(Interpreter.java:332)
  at ch.qos.logback.core.joran.GenericConfigurator.doConfigure(GenericConfigurator.java:126)
  at ch.qos.logback.core.joran.GenericConfigurator.doConfigure(GenericConfigurator.java:93)
  at ch.qos.logback.core.joran.GenericConfigurator.doConfigure(GenericConfigurator.java:52)
  at ch.qos.logback.classic.util.ContextInitializer.configureByResource(ContextInitializer.java:77)
  at ch.qos.logback.classic.util.ContextInitializer.autoConfig(ContextInitializer.java:150)
  at org.slf4j.impl.StaticLoggerBinder.init(StaticLoggerBinder.java:85)
  at org.slf4j.impl.StaticLoggerBinder.<clinit>(StaticLoggerBinder.java:55)
  at org.slf4j.LoggerFactory.bind(LoggerFactory.java:121)
  at org.slf4j.LoggerFactory.performInitialization(LoggerFactory.java:111)
  at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:268)
  at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:241)
  at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:254)
......
This happens because ch.qos.logback.core.util.ContextUtil.java contains are reference to a java.net.InetAddress which is a restricted class on Google AppEngine Platform SDK 1.3.7:
  static String getLocalHostName() throws UnknownHostException {
    InetAddress localhost = InetAddress.getLocalHost();
    return localhost.getHostName();
  }
I should note that BasicConfigurator is working and is able to configure the logback subsystem.
A couple of resolutions I can think of:
1. Don't export this parameter by default, instead let the user choose if to define it or not in the logback.xml configuration file.
2. Create a "GAEConfigurator" which will use default for the limited GAE environment.
2. Provide a custom build for GAE platform, where this parameter will be taken from http://code.google.com/appengine/docs/java/javadoc/com/google/appengine/api/... or not be defined at all.
4. Provide some method to override / use a different implementation of ContextUtil, one which will be suitable for GAE.
-- 
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: http://jira.qos.ch/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira

[logback-dev] [JIRA] Commented: (LBCORE-171) Can't use logback on GAE SDK 1.3.7 when configured with logback.xml

Maxim Veksler (JIRA)