Apache Karaf Decanter 2.4.0 will be released soon and include a set of new collectors.
The oshi collector harvest a bunch of data about the hardware and the operating system. It’s a scheduled collector, executed periodically (every minute by default).
You can have all details about the machine thanks to this collector: motherboard, cpu, sensors, disks, etc, etc.
By default, the oshi collector retrieves all details, but you can filter what you want to harvest in the
etc/org.apache.karaf.decanter.collector.oshi.cfg configuration file.
It means now we have the system collector that allows you to periodically execute scripts and shell commands, and the oshi collector that harvests all details about the system.
The ConfigAdmin collector is a event driven collector. It “listens” for any change on the Karaf configuration and send an event for each change.
Karaf Decanter 2.3.0 introduced the Prometheus appender to expose metrics on a Prometheus servlet exposed by Decanter.
On the other hand, the Prometheus collector is able to “parse” a Prometheus servlet to get the gauges and creates the corresponding event.
Like we have the Elasticsearch appender to store collected data in Elasticsearch, the Elasticsearch collector is a scheduled collector that periodically executes a search on Elasticsearch instance. The documents hits are created as event sent into Decanter.
Again, as we have the Redis appender to store collected data in Redis map, the Redis collector periodically retrieves key-value pairs (eventually using key pattern).