Expert Domain-Driven Design (DDD) Implementation in .NET

Course details

This course is aimed at .NET developers and architects interested in applying domain-driven design (DDD) in their projects. Instructor Rodrigo Díaz Concha takes you through the steps for creating a solution for a fictional pet medicine company to show you practical techniques to implement DDD using .NET and C#. Learn about using entities, value objects, aggregates, domain events, and more. This course is ideal for those looking to integrate DDD strategies and tools into their development solutions, as well as for software architects and .NET project stakeholders who want to understand how to implement DDD in their current or future initiatives.

Learning objectives
Structure your application around domains and entities.
Establish aggregate classes and determine appropriate behaviors.
Interact with your domains through events and commands.

Concepts

Introduction

Unleash the power of Domain-Driven Design in your .NET projects
What you should know
Preparing the development environment
Domain-Driven Design refresher
Understanding what you are going to build

Defining and Implementing Entities and Value Objects

Creating the initial project for the Management domain model
Implementing an entity
Refactoring the logic into an entity base class
Encapsulating and protecting entity state
Avoiding the primitive obsession anti-pattern
Implementing a value object for a pet's weight
Implementing a second entity for pet breeds
Invoking a domain service in a value object
Implementing business rules in the Pet entity
Implementing implicit operators in value objects

Defining and Implementing Aggregates

Refactoring the solution to add a shared kernel mapping
Adding necessary properties to the aggregate
Implementing logic in the aggregate to end a consultation
Implementing behavior to manage drugs
Implementing behavior to record multiple vital sign readings
Unit testing the aggregate

Implementing the Infrastructure Layer

Creating the ManagementDbContext
Configuring type and property mappings in the DbContext
Registering the DbContext in the dependency injection container
Refactoring the code into a repository interface and class

Implementing the Application Layer

Implementing the ManagementApplicationService class
Persisting data in the ManagementApplicationService class
Rehydrating persisted entities and invoking their behavior
Creating a command handler interface for handling commands
Challenge - Implementing the Clinic API
Solution - Implementing the Clinic API
Challenge - Refactoring the consultation date and time
Solution - Refactoring the consultation date and time

Implementing Domain Events

Implementing domain events
Publishing domain events
Subscribing to domain events

Mixing the Event Sourcing Pattern with DDD

Refactoring the AggregateRoot class for tracking events
Implementing the first domain event to be tracked
Implementing more domain events related to the consultation
Refactoring the DbContext for handling domain events
Persisting domain events in the database
Loading domain events from the database

Conclusion

Next steps in Domain-Driven Design (DDD)