Modular Monolith with DDD: A Comprehensive Introduction
Introduction
The Modular Monolith with Domain-Driven Design (DDD) project is an exemplary .NET application aimed at demonstrating how to effectively implement a modular monolithic application using best practices and design patterns. It is a robust system designed not only as a theoretical concept but as a practical, production-ready solution.
Purpose of the Repository
The primary objectives of this repository include:
- Modular Monolith Implementation: Showcasing how a monolithic application can be structured in a modular fashion.
- Complete Application Development: Unlike basic applications, this project demonstrates a fully-functional application designed for production use.
- Best Practices and Design Patterns: Applying object-oriented programming principles and design patterns appropriately.
- Domain-Driven Design (DDD): Employing DDD tactical patterns for organizing code around domains for better manageability and maintainability.
- Testing Philosophy: Developing robust unit tests, integration tests, and exploring event sourcing.
- Architecture Insights: Presenting the C4 Model for architectural clarity and discussing architectural decisions in detail.
Domain Overview
Selected Domain
The project focuses on a domain inspired by Meetup Groups, similar to the functionality offered by Meetup.com. The domain includes entities such as Members, Meeting Groups, and Meetings.
Key Features
- Members: Can create or join meeting groups, attend meetings, and interact through comments.
- Meeting Groups: Organized by a member, these groups are the primary organizers of meetings.
- Meetings: Events with defined roles such as hosts, attendees, and possibly additional guests.
This domain is chosen for its relatability, balance of complexity, and applicability, ensuring it is both understandable and non-trivial.
Architecture
Overview
The architecture of the project follows the C4 Model which provides a clear graphical notation technique for representing the architecture of software systems. This model divides the architecture into four levels: System Context, Container, Component, and Code.
High-Level Description
- API Layer: Serves as a thin interface to handle REST API requests, and is responsible for routing these requests to appropriate modules.
- Modules: Consist of User Access, Registrations, Meetings, Administration, and Payments, each handling specific parts of the application’s logic.
- Events Bus: Facilitates asynchronous communication between modules, promoting a cleaner separation of concerns.
Module Structure
Each module is designed following the Clean Architecture principles and is composed of:
- Application: Manages the processing of requests and coordinates domain logic.
- Domain: Implements business rules within a bounded context.
- Infrastructure: Manages external communications, data storage, and other infrastructural concerns.
- IntegrationEvents: Defines contracts for events that the module publishes to the event bus.
Running and Contribution
To run the application or contribute, follow the detailed setup instructions provided in the repository. Contributions are encouraged, following guidelines outlined to ensure code quality and consistency.
Authors and License
The project is authored by skilled contributors and is open-source, licensed under a permissive license to facilitate widespread use and adaptation.
Inspirations and Recommendations
For those looking to delve deeper into software architecture and domain-driven design, the repository provides references and recommendations to guide further learning and exploration.