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Host Logger Microservice

The logger microservice ingests workflow log events produced by the DTaaS client and stores them as JSON Lines (.jsonl) files.

This page explains how to run the logger microservice as a standalone docker container.

Setup

Place a logger.yaml configuration file in the directory from which compose.logger.yml will be run. Download the sample configuration and use it as a template:

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curl -o logger.yaml \
  https://raw.githubusercontent.com/INTO-CPS-Association/DTaaS/feature/distributed-demo/servers/logger/config/logger.yaml.sample

The captured events go to a logs directory in the same location. The logger runs as the node user (uid 1000), so create the directory and, on Linux hosts, give it to uid 1000:

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mkdir logs
sudo chown -R 1000:1000 logs

If the logs directory does not exist, Docker creates it as root. Images before 0.1.2 cannot write into such a directory.

Use

Use the docker compose file to start the service.

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# To bring up the container
docker compose -f compose.logger.yml up -d
# To bring down the container
docker compose -f compose.logger.yml down

Service Endpoints

The health check URL: localhost:4003/logger/health

The event ingestion URL: localhost:4003/logger

The configuration options are described in the npm package page and the service is described on the user page.