One of the major features of Clowder is the ability to deploy custom extractors for when files are uploaded to the system.

A full list of extractors is available in Bitbucket.

To write new extractors, pyClowder is a good starting point. It provides a simple Python library to write new extractors in Python. Please see the sample extractors directory for examples.

That being said, extractors can be written in any language that supports HTTP, JSON and AMQP (ideally a RabbitMQ client library is available for it).