Hello World :)

These are the parties involved:

• payments: The payments core. Is a DDD payments core which allow payment request/reject/approval.
• contractor_web_ui: a web UI for contractors. It publishes the payment_requested event to the msg broker, handles the payment_accepted and payment_rejected events coming from the msg broker.
• manager_web_ui: a web UI for managers. It publishes the payment_accepted and payment_rejected events to the msg broker, and handles the payment_requested event coming from the msg broker.
• relational DB's for each web UI: contractor and manager for storing the local copy of the payment request aggregates.
• message broker Kafka for serving as message bus between the 2 web_uis

Process model:

• There are 2 processes for each app. Karafka & rails web UI
• In addition to those there are the docker managed containers runing the zookeeper & kafka & postgresql processes & redis.

Role of each process:

• Kafka serves as a message bus for exchanging events between the consumer and manger app.
• Redis serves the Turbo Websocket for Rails 7 for the Realtime UI update.
• Postgresql acts as a Relational Database for both Contractor and Manager apps.

Steps to launch:

• docker compose up
• cd contractor_web_ui && bundle install && bundle exec rails db:setup && foreman start
• open a new terminal app
• cd manager_web_ui && bundle install && bundle exec rails db:setup && foreman start

Steps to play after launch:

• Step.0.1: open http://localhost:3000. Let's call this: Tab1. This incorporates the Contractor Web UI.
• Step.0.2: open a new browser tab and open http://localhost:4000. Let's call this: Tab2. This incorporates the Manager Web UI.
• Step.1: In Tab1: click request new payment. Then fill the form and request a new payment
• Step.2: The payment request added in the Tab1 should appear in Tab2. Now reject/approve as You wish in Tab2
• Step.3: Go backIn Tab1. The payment request should have the same state as it was modified in the Tab2 by the manager.

For the evaluation:

• Controller classes:

  • manager_web_ui/app/controllers/payment_requests_controller.rb
  • contractor_web_ui/app/controllers/payment_requests_controller.rb

• Event Handling Code:

  • manager_web_ui/app/consumers/payments_consumer.rb
  • contractor_web_ui/app/consumers/payments_consumer.rb

Architecture: