Elasticsearch technologies

Suppose you have a system with ElasticSearch server installed and need to upgrade it to a newer version. Below is a step-by-step guide explaining how you can do it, but note that it only works for ElasticSearch pre-1.x versions. It's also assumed that you have already stopped your ElasticSearch cluster before upgrading.

Grails, gorm technologies

Assume you have a page with pagination that displays some objects table (selected from DB with GORM criteria) in your Grails application. If you want to know total number of possible results (as if there are no pagination parameters), you can do it in this way:

Zeromq, scala, akka technologies

I had a chance to try akka-zeromq module last month in order to implement solution for inter-service communication using Scala, Akka 2.0 and ZeroMQ.

Grails, plugin, configuration, howto technologies

This code snippet shows how to update project configuration settings from a Grails plugin executable script. The script changes the configuration by copying the settings from a default config file, placed in the plugin's folder, to the Config.groovy. This is usually very useful during a plugin installation when you need to provide some default configuration:

Grails, spock technologies

I've faced a problem with unit testing web flow controllers

There's an existings WebFlowUnitTestMixin for unit testing webflow in GDK, but no word on how to use it in the latest Grails 2.2.0 official documentation.