Configuring Tremor

This is a short canned synopsis of tremor configuration.

Tremor supports dynamic reconfiguration since v0.4.

Introduction

The tremor runtime is internally structured with multiple types of artifacts:

• Connectors - Specify to tremor how to connect to the outside world. For example, the kafka consumer connector consumes data from Kafka topics.

• Pipeline - Specify to tremor what operations to perform on data ingested ( from any connected upstream source ) and what to contribute or publish downstream ( to any connected downstream target ).

• Deployments - Definen how pipelines and connectors are deployed together.

Each artifact consists of a definition and an instantiation. Definitions can be re-used for multiple instances, as a kind of template.

Live connectors and pipelines in tremor are in a runnable state. They consume typically network bandwidth and some compute in the case of connectors. They consume compute time in the case of pipelines.

Using the docker image

When using the tremor docker image configuration is loaded from the folder /etc/tremor this folder should be mounted into the docker container to propagate the data.

The following files are looked for:

• /etc/tremor/logger.yaml a log4rs configuration file to control logging in tremor.
• /etc/tremor/config/ : All *.troy files in this directory and its subdirectories will be loaded and run.

By default tremor is looking into /usr/local/share/tremor for custom modules and libraries that can be included in other files via use. See modules. To adapt the places tremor is looking for your modules, append to the TREMOR_PATH environment variable:

export TREMOR_PATH="/my/custom/tremor_modules:$TREMOR_PATH"