News & Articles

A series of technical articles on modern cloud-based software design and applications

Microservices Context-Based Configuration Approach

Microservices have become enormously popular mainly due to the introduction of Docker containers and cloud resource schedulers such as Mesos. With all the advantages of distribution that they bring, microservices migrate considerable complexity from development to deployment. Some of this relates dynamic and context-based configuration.

Efficient Cassandra Write Pattern for Data Streaming

Cassandra is a strong candidate for storing streaming data such as time series. Therefore it is typically used in combination with Apache Storm or Apache Spark.The fastest option for writing to a Cassandra cluster is through concurrent asynchronous writes. However, in cases where data exhibits strong temporal locality, the performance can be further improved.

Jolokia in Karaf 3.0.x – Fixing the 403 access error

The latest version of Jolokia – 1.2.1 running in the latest version of Karaf – 3.0.1 fails with an HTTP 403 error. The issue applies only when the jolokia-osgi bundle which depends on the OSGi HTTP service is deployed. The master branch in Jolokia which is not released yet contains a fix for this issue and introduces 2 new configuration properties specific to this.

Exporting Camel Endpoints as OSGi Services

It is often useful to proxy calls to services exported by a Blueprint context through a service bus. The bus could be used to log incoming calls, adapt/filter the call arguments and the result, transparently forward requests to a remote OSGi container, broadcast to several remote containers or forward to the more powerful Fuse Fabric endpoints. Exporting a regular interface to a Camel endpoint is key to this functionality.