Harald Pehl

Developer notes written down before they get lost.

Polyglot DMR

The dynamic or detyped model representation (DMR) is an API to interact with the management model of a running WildFly instance. There’s an Java API available at https://github.com/jbossas/jboss-dmr which is described in the WildFly Wiki. Though the Java API is very rich and powerful it is somewhat hard to write scripts that perform useful tasks like

  • Periodically read the memory and send an SMS / tweet / email when a threshold is reached
  • Rollout a deployment over all servers in a cluster
  • Monitor the state of an application

Send Mails From OpenShift

OpenShift is a great place to host your applications. In this post I’m going to show you how you can easily send mails from your JEE applications running on JBoss. For sending mails I’m going to configure an external SMTP server. Any SMTP server will do, I’m going to use GMail.

HTTP Caching

I recently implemented caching for distinct operations of the HTTP management API in WildFly. As a preparation I did some research on HTTP caching and how it’s best implemented on the server side. A really good introduction is the caching tutorial by Mark Nottingham. I’ll discuss the key points in this blog post.

Web Components

I recently watched Eric Bidelmans presentation on Web Components at Google IO 13. Web Components is an effort to bring true modularisation to web development. For the first time you’ll have encapsulation at the browser level. No more mess with duplicate IDs or mixed CSS style rules.

Moved Blog to GitHub Pages

For over three years I was hosting my blog at Blogger.com. Although publishing was quite easy I never was really happy with the layout and the support for customization.

Hosted CI Services

I was looking for a hosted continuous integration service to build my GitHub projects. My requirements are painless GitHub integration, easy setup and a simple and straightforward UI. I looked at two services: Drone.io and Travis CI. In this post I will outline my very personal experience with it.

Playing Around With Dart Isolates

I was looking for a way to implement some kind of dynamic plug-in system in Dart. The idea was to load Dart code on demand into an isolate using spawnUri(). It turns out that this function is implemented in the Dart VM but neither in Dartium nor does it compile down to JavaScript.