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1 services are in this domain

This service sends messages to downstream consumers

Overview

The Finance domain serves as the backbone of BookWorm’s monetary operations, handling all financial transactions across the platform. This support domain manages basket reservations, order processing workflows, payment processing, refund mechanisms, and financial reporting.

Key responsibilities include:

  • Orchestrating the financial aspects of order fulfillment
  • Managing payment gateway integrations
  • Handling billing and invoicing processes
  • Processing refunds and adjustments
  • Providing financial reporting and analytics
  • Ensuring compliance with financial regulations
  • Managing discount and promotion calculations

The Finance domain communicates with multiple other domains through event-based messaging, particularly with Ordering and Basket services. It maintains its own ledger of transactions while providing a consistent financial view across the entire BookWorm platform.

Technical Implementation

The Finance service is implemented using an event-driven architecture with a state machine-based saga pattern to coordinate the order processing workflow. Key components include:

State Machine Workflow

The service implements a robust order state machine with the following states:

  • Placed: Initial state when an order is placed
  • Completed: Final state for successfully processed orders
  • Cancelled: State for orders that have been cancelled
  • Failed: State for orders that encountered errors during processing

Event Flow

The Finance service processes the following key integration events:

  • UserCheckedOutIntegrationEvent: Triggered when a user completes checkout
  • OrderStatusChangedToCompleteIntegrationEvent: Signals order completion
  • OrderStatusChangedToCancelIntegrationEvent: Signals order cancellation
  • BasketDeletedCompleteIntegrationEvent: Confirms successful basket deletion
  • BasketDeletedFailedIntegrationEvent: Indicates failure in basket deletion

Commands

The service issues various commands to coordinate the order processing workflow:

  • PlaceOrderCommand: Initiates the order processing
  • CompleteOrderCommand: Finalizes a successful order
  • CancelOrderCommand: Processes order cancellation
  • DeleteBasketCompleteCommand: Handles successful basket cleanup
  • DeleteBasketFailedCommand: Manages failed basket deletion scenarios

Query Capabilities

The Finance service provides query endpoints to retrieve order state information:

  • GetOrderStateQuery: Allows retrieval of current order state and details

Bounded context

Messages for this domain

Sends messages (5)

Quickly find the message you need by searching for the name, type, or summary.
NameVersionTypeSummary
Cancelled Order
v1.0.0eventReceive a message when an order is canceled
Completed Order
v1.0.0eventReceive a message when an order is completed
Deleted Basket Complete
v1.0.0eventRepresents a domain event that is published when reverse basket is completed
Deleted Basket Fail
v1.0.0eventRepresents a failed integration event when deleting a basket in the system

Receives messages (6)

Quickly find the message you need by searching for the name, type, or summary.
NameVersionTypeSummary
Get Order State Machine
v1.0.0queryGet order state machine
Deleted Basket Complete
v1.0.0eventRepresents a domain event that is published when reverse basket is completed
Deleted Basket Fail
v1.0.0eventRepresents a failed basket deletion event in the system
Changed Order Status To Cancel
v1.0.0eventRepresents an integration event when an order status is changed to cancel