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Shipping Fleet Management

This microservice is responsible to support simulation of fleet of container carrier vessels. It used for demonstration purpose, but it is still using an event-driven microservice implementation approach. It supports the event, actors, and commands discovered during the event storming workshop and illustrated by the following figure for the "ship actor".

Overview

Description: The service exposes simple a REST API to support acquiring ship and fleet information, while also providing simulation control to emulate ship movements and container metrics event generation. When a ship leaves or enters a port, it will also generate the events as listed in the Event Storming Analysis and Domain-Driven Design results.

Github repository: refarch-kc-ms

Folder: fleet-ms

Kafka topics consumed from:

Kafka topics produced to:

Events reacted to:

Events produced:

EDA Patterns implemented:

Build

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-fleet-ms[: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.

Run

Deployment parameters

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

NameRequiredDescription
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.
TRUSTSTORE_ENABLEDNORequired to be set to true when connecting to IBM Event Streams on the IBM Cloud Pak for Integration (CP4I).
TRUSTSTORE_PATHNOThe local path to the required truststore file when connecting to IBM Event Streams on CP4I. See Volume Mounts below.
TRUSTSTORE_PWDNOThe password for the truststore file used for IBM Event Streams server verification.
KAFKA_SHIP_TOPIC_NAMEYESThe topic name used for communication relating to the ship entity.
KAFKA_CONTAINER_TOPIC_NAMEYESThe topic name used for communication relating to the containers entity.
KAFKA_BW_PROBLEM_TOPIC_NAMEYESThe topic name used for communication relating to the bluewater problems domain.

Volume Mounts

The Fleet Management microservice requires up to one file to be injected at runtime for proper operation. As noted in the TRUSTSTORE_PATH 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 TRUSTSTORE_PATH 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.jks:/config/resources/security/es-ssl/es-cert.jks in its --docker-options string to run this microservice locally.

Example: appsody run --docker-options "-v /Users/myuser/Downloads/es-cert.jks:/config/resources/security/es-ssl/es-cert.jks " ...

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 KAFKA_SHIP_TOPIC_NAME=ships -e KAFKA_CONTAINER_TOPIC_NAME=containers -v /Users/myuser/Downloads/es-cert.jks:/config/resources/security/es-ssl/es-cert.jks" ...

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-fleet-ms[: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

REST APIs