released the newest version of its open source application server, Resin. Version 4.0.2
has bigger changes than the small number change implies. The release includes Servlet 3.0 Early Access improvements such as file upload and annotations. Resin 4.0.2 also has Quercus
compatibility fixes, Eclipse plugin updates, improved administration application monitoring, and a new Git-based deployment architecture. One of the most significant features of this release is support for a REST interface in the Resin administration application. The new REST interface in Resin 4.0.2 provides easy monitoring application access to the server state programmatically.
The Resin administration application is written in PHP using Quercus, Caucho's Java implementation of PHP 5. Resin provides a PHP framework to access server MBeans and output information. The Resin administration application will take care of script calling and MBean access. All the developer needs to do is write a PHP script with a .rest extension in order to create a REST resource. For example, you can print the status of of your Resin thread pool by writing a simple request with many facilities provided automatically. The Resin Server MBean and generic JVM Threading MBean codes are used to get the current thread status. The data can then be put into an external monitor.
The REST interface can also be integrated with popular monitoring applications such as Nagios
. Nagios can monitor resources exposed through the REST interface. The plugin mechanism in Nagios can use a shell script to integrate with the Resin REST engine by accessing memory, thread, and uptime resources. When the integration is set up
, monitoring another resource requires only a few lines of code. JConsole or the Resin administration application's JMX view can be used to find other MBeans to monitor. Developers can also monitor their own MBeans and share their scripts in the Caucho forum
Caucho offers two editions for Resin. The Resin Professional edition is for professional production environments and Resin Open Source a free offering for hobbyists, developers, and low traffic websites. Resin Open Source is licensed under the GNU public license.