Showing posts from 2015

What's new in Apache Karaf Cellar 4.0.0 ?

Apache Karaf Cellar 4.0.0 release is now on vote, and hopefully, it should be available very soon. This release is a major new release. More than just bug fixes, this release brings several refactoring and new features. It’s time to take a tour in the new Cellar 4.0.0. HTTP features Cellar 4.0.0 brings new HTTP features. HTTP load balancer Cellar 4.0.0 provides a new feature: cellar-http-balancer. The purpose is to use any nodes in a cluster group to access a web application, even if the web application is not actually deployed on the local node. For instance, you have a cluster group containing four nodes. You deploy a web application on two nodes. So basically, to access your web application, you have to: specify the address of one of two nodes where the web application is deployed in your browser use a load balancer (mod_proxy_balancer, Cisco, Juniper, F5, whatever) to load balance on the two nodes. The drawback of this is that the load balancer is a single point of failure, and add

Talend ESB: query a database directly in the mediation perspective

When exposing a database as a REST or SOAP service, lot of users use: the integration perspective to create a service, but they don’t leverage Camel the mediation perspective to create a route containing a cTalendJob However, there’s an easy alternative. Using the mediation perspective, we can use directly a datasource exposed in the runtime (Karaf) as an OSGi service, and directly use Camel components. The advantages of this approach are: The same DataSource is shared by different routes and services. It means that we can use a PooledDataSource and optimize the connections to the database. We don’t use any Talend job, and directly leverage Camel native components. Route design in the studio We create a route in the mediation perspective of the studio. First, in the Spring tab, we add the DataSource OSGi service lookup. To do so, we add the spring-osgi namespace and use the osgi:reference element: <beans .... xmlns:osgi="" xs

Monitoring and alerting with Apache Karaf Decanter

Some months ago, I proposed Decanter on the Apache Karaf Dev mailing list . Today, Apache Karaf Decanter 1.0.0 first release is now on vote . It’s the good time to do a presentation 😉 Overview Apache Karaf Decanter is complete monitoring and alerting solution for Karaf and the applications running on it. It’s very flexible, providing ready to use features, and also very easy to extend. Decanter 1.0.0 release works with any Karaf version, and can also be used to monitor applications outside of Karaf. Decanter provides collectors, appenders, and SLA. Collectors Decanter Collectors are responsible of harvesting the monitoring data. Basically, a collector harvest the data, create an OSGi EventAdmin Event event send to decanter/collect/* topic. A Collector can be: Event Driven, meaning that it will automatically react to an internal event Polled, meaning that it’s periodically executed by the Decanter Scheduler You can install multiple Decanter Collectors in the same time. In the 1.0.0 re