jbonofre's blog

Recently, I had the question several times: how can I have metrics (number of requests, request time, …) of the SOAP and REST services deployed in Apache Karaf or Apache Unomi (also running on Karaf). SOAP and REST services are often implemented with Apache CXF (either directly using CXF or using Aries JAXRS whiteboard which uses CXF behind the hood). Apache Karaf provides examples how to deploy SOAP/REST services, using different approaches (depending the one you prefer): https://github.com/apache/karaf/tree/master/examples/karaf-soap-example https://github.com/apache/karaf/tree/master/examples/karaf-rest-example CXF Bus Metrics feature Apache CXF provides a metrics feature that collect the metrics we need. Behind the hood it uses dropwizard library and the metrics are exposed as JMX MBeans thanks to the JmxExporter . Let’s take a simple REST service. For this example, I’m using blueprint, but it also works with CXF programmatically or using SCR. I have a very simple ...

We are heading to Christmas time, and the Karaf team wanted to prepare some gifts for you 😉 Of course, we are working hard in the preparation of the new Karaf releases. A bunch of bug fixes and improvements will be available in the coming releases: Karaf 2.4.1, Karaf 3.0.3, and Karaf 4.0.0.M2. Some sub-project releases are also in preparation, especially Cellar. We completely refactored Cellar internals, to provide a more reliable, predictable, and stable behavior. New sync policies are available, new properties, new commands, and also interesting new features like HTTP session replication, or HTTP load balancing. I will prepare a blog about this very soon. But, we’re also preparing brand-new features. Docker.io I heard some people saying: “why do I need Karaf when I have docker.io ?”. Honestly, I don’t understand this as the purpose is not the same: actually, Karaf on docker.io is a great value. First, docker.io concepts are not new. It’s more or less new...

Introduction Apache Camel has not be designed to be used for implementing batch tasks. For instance, if your Camel route has a consumer endpoint polling files in a directory, Camel will periodically and indefinitely monitor the folder and poll any new incoming files. It’s not a batch behavior: in batch mode, we want to run the file polling on demand, at a certain time, launched by a batch scheduler like ControlM, $Universe or Tivoli Worksheet Scheduler. However, there are several interesting points to use Camel for batch implementation. First, Camel provides a large set of components. A lot of batches read/write files, read from a JMS queues, write into JMS queues, etc. Usage of Camel components in a batch way is really valuable. Second, Camel uses a DSL to describe the process executed by the routes. Especially, it supports “human readable” DSL like Spring XML or Blueprint XML. It means that it’s easy to review what the batch is doing, eventually change an endp...

Apache CXF provides a really great layer to implement JAX-RS services. Especially, it fully supports OSGi, including Blueprint. It means that you can very easily create and deploy your REST services in a Apache Karaf container. In this example, we will see how to list all Karaf features via a REST service. This exemple is composed by three modules: – common is an OSGi bundle containing resources shared between the JAX-RS server and the clients. Basically, it contains the service interface and the objects used in the service. – service is an OSGi bundle providing the implementation of the service interface – client is a simple Main class that use CXF JAX-RS client Common bundle This bundle contains the interface describing the behavior of the REST service. We define it in the FeaturesRestService : package net.nanthrax.examples.jaxrs.common; import javax.ws.rs.GET; import javax.ws.rs.Path; import javax.ws.rs.Produces; import java.util.Collection; /** * REST service to m...