mgohashi / event-streams

TDC2019 - Event Streams Example

Sample Coffee Bar - Event / Reactive System

Modules

• vagrant: Vagrant environment with Ansible provisioner to provide an environment with Kafka and MySQL;
• coffee-model: Model project to reuse data POJOs between projects;
• coffee-store: Vert.x App Store project to generate orders and control its statuses;
• coffee-stock: Vert.x App Stock project to control the product stock items;
• coffee-machine: Vert.x App Machine project to simulate the machine running;
• coffee-monitor: Vert.x with Angular App Monitor project to have an overview of the system running;

Valid States for an Order

• placed: Order is pre validated;
• confirmed: The order has enough ingredients available;
• delivered: The order has finished its preparation process;
• canceled: The order has been canceled due to out of stock items.

Event Streams / State transitions / Kafka Topics

• test-order-submitted: User interaction event to submit orders;
• test-order-placed: After the order has been pre validated the other is accepted by the system;
• test-order-confirmed: After the order has been validated against required stock products;
• test-order-preparation-started: After the order has started the preparation process;
• test-order-preparation-finished: After the order has finished from the preparation process;
• test-order-canceled: After the order has been canceled due to out of stock products.

Running the modules

• Download Kafka from https://kafka.apache.org/ and place it under the [BASE_DIR]/event-streams/vagrant/roles/kafka/files

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  NOTE

  This script is expecting to have the following version: kafka_2.12-2.2.0.tgz

  ---

• vagrant: $ vagrant up

• coffee-stock: $ mvn exec:java -pl coffee-stock

• coffee-machine: $ mvn exec:java -pl coffee-machine

• coffee-store: $ mvn exec:java -pl coffee-store

• coffee-monitor: $ mvn exec:java -pl coffee-monitor

Monitor

• After successfully executed open the dashboard at: http://localhost:8080