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Telemetry Simulator

The telemetry simulator component is a Python-based application for generating anomalous data events for refrigerated shipping containers (also known as 'reefers').


Description: The Simulator webapp is a simple python (3.7) flask web app exposing a REST POST end point to control the type of simulation to run and to produce Reefer telemetry events to kafka reeferTelemetry topic.

This microservice has been implemented using the Appsody Python Flask stack.

Simulator diagram

Github repository: refarch-reefer-ml

Folder: simulator

Kafka topics consumed from: None

Kafka topics produced to:

Events reacted to: None

Events produced:

EDA Patterns implemented: None


This microservice is built using the Appsody development framework. The Appsody CLI is a required prerequisite for building the application locally.

Appsody will build the application by pulling the contents of the Appsody Stack it is based on and then performing the local application build inside the containerized environment:

appsody build -t <yournamespace>/kcontainer-reefer-simulator-appsody[:tag] [--push]

  • You can optionally specify a container tag. If left blank, latest will be used.
  • You can optionally supply the --push flag to automatically push the built image to specified remote repository.

Performing an Appsody build will update the app-deploy.yaml file in the same directory with current information for the application image, labels, and annotations fields.


Deployment parameters

The following deployment parameters are defined in the app-deploy.yaml file:

KAFKA_BROKERSYESComma-separated list of Kafka brokers to connect to
KAFKA_APIKEYNOAPI Key used to connect to SASL-secured Kafka brokers. This is required when connecting to IBM Event Streams clusters.
KAFKA_CERTNOThe local path to the required certifcate file when connecting to IBM Event Streams on CP4I. See Volume Mounts below.
CONTAINER_TOPICYESThe topic name used for communication relating to the containers entity.
TELEMETRY_TOPICYESThe topic name used for communication relating to the reefer telemetry entity.

Volume Mounts

The Voyage Management microservice requires up to one file to be injected at runtime for proper operation. As noted in the KAFKA_CERT parameter above, these files are SSL-based certificates which are required to verfiy the identity of the external service when calling it. These files are provided as --docker-options "-v host-src:container-dest ..." when running the microservice locally and as a Volume Mount when running the microservice on a Kubernetes cluster.

The KAFKA_CERT parameter is documented in the Event Streams Certificates section of the Prerequisites page. The Appsody run command should include a parameter similar to -v /Users/myuser/Downloads/es-cert.pem:/certs/es-cert.pem in its --docker-options string to run this microservice locally.

Example: appsody run --docker-options "-v /Users/myuser/Downloads/es-cert.pem:/certs/es-cert.pem" ...

Running the microservice locally

When running the microservice locally, you must specify all the required deployment parameters from above as environment variables via the --docker-options flag being passed in from the Appsody CLI command.

Example: appsody run --docker-options "-e KAFKA_BROKERS=remotebroker1:9092,remotebroker2:9092 -e CONTAINER_TOPIC=containers -v /Users/myuser/Downloads/es-cert.pem:/certs/es-cert.pem" ...

For more details on running the microservice locally, consult the Appsody run documentation as well as the deployment information contained in the app-deploy.yaml file.

Running the microservice remotely

The Appsody Operator is a required prerequisite for deploying the microservice to a remote Kubernetes or OpenShift cluster.

To deploy the microservice to a remote cluster:

appsody deploy <yournamespace>/kcontainer-reefer-simulator-appsody[:tag] --no-build

  • You can omit the --no-build flag to have Appsody perform a build before deploying the application.
  • Note: Performing a build at deploy time requires specifying the absolute container reference path, as well as the --push flag.
  • The neccesary deployment parameter information will be read from the app-deploy.yaml file in the same directory.

Usage Details