Pull Request Description

This pull request implements the Chassis Pattern by creating a new BookWorm.Chassis project to house all infrastructure and cross-cutting concerns, while keeping only essential domain primitives in the BookWorm.SharedKernel. This architectural refactoring aligns with Domain-Driven Design principles by clearly separating technical infrastructure from domain concepts.

Changes

• Created new BookWorm.Chassis project to contain infrastructure and cross-cutting concerns
• Moved the following components from SharedKernel to Chassis:
  • Infrastructure: ActivityScope, EventBus, OpenTelemetry, Logging, Mediator
  • Cross-cutting concerns: Command, Query, Pipelines, Exceptions, Guards, Versioning
  • Data access: EF, Repository, Specification
  • Utilities: Converters, Endpoints, Mapper
• Kept only domain primitives in SharedKernel:
  • Domain building blocks: Entity, ValueObject, IAggregateRoot, AuditableEntity, ISoftDelete, PagedResult
  • Domain events

Motivation

Chassis Pattern

The Chassis Pattern provides a foundation for applications by centralizing technical infrastructure, cross-cutting concerns, and common utilities. This pattern:

• Creates a consistent technical foundation across services
• Reduces duplication of infrastructure code
• Enforces standardized approaches to common concerns (logging, telemetry, etc.)
• Simplifies onboarding by providing a well-defined technical framework

Why Move to Chassis

This refactoring moves infrastructure concerns to BookWorm.Chassis because:

1. SharedKernel Should Focus on Domain - In DDD, the SharedKernel should contain only the essential domain primitives shared across bounded contexts, not technical implementation details
2. Separation of Concerns - Domain model should be isolated from infrastructure to maintain clean architecture
3. Reduced Coupling - Domain logic can evolve independently from infrastructure concerns
4. Improved Testability - Domain models can be tested without infrastructure dependencies
5. Better Maintainability - Clear boundaries between domain and infrastructure make the codebase easier to understand and maintain

Checklist

• My code follows the DDD principles
• I've used the latest C# features and idioms
• I've added/updated unit tests for business logic
• Service boundaries are maintained (no cross-service direct dependencies)
• Repository pattern is used for data access
• Domain Events are used for cross-service communication
• I've registered new services in AppHost project (if applicable)
• I've updated both entities and DTOs (if applicable)