Sample Food Delivery API With Marten

Project Objective

The aim of this project is to simulate a Food Delivery Application.

Main Entities

• Order
• Rider

Flow Description

1. An order is initially created with a default status (New).
2. A rider accepts an order, triggering an event stream start and dispatching an OrderAccepted event.
3. The rider updates their location to track the order's progress, with a LocationUpdate event dispatched for each new location.
4. The Order Aggregate entity reflects the result of order and rider updates. There are two ways to retrieve an aggregate:
   • Live Aggregation: Evaluating all events from the database each time you request the data.
   • Snapshot Aggregation: Stored in memory using Marten.

Minimal API with AOT Compilation

Minimal APIs are designed for creating HTTP APIs with minimal dependencies, ideal for microservices and applications requiring minimal files, features, and dependencies in ASP.NET Core. Learn more

Publishing your app as Native AOT produces a self-contained app that's been ahead-of-time (AOT) compiled to native code. Native AOT apps boast faster startup times and smaller memory footprints, and they can run on machines without the .NET runtime installed. Learn more

Note: Marten and projection cannot work with AOT compilation because dynamically generated code is not allowed.

Event Sourcing and CQRS in Microservices

What is CQRS?

Command Query Responsibility Segregation (CQRS) is a pattern that separates the read and write operations of a system into distinct paths. Learn more

To implement the CQRS pattern, a Mediator Library is employed to manage Queries and Commands. MediatR

In combination with MediatR, FluentValidation is used to validate Queries and Commands before they hit the handlers. FluentValidation

Event Sourcing

Event Sourcing captures every change to an application’s state as a sequence of immutable events, maintaining a full history of state changes. Learn more

Benefits of Event Sourcing and CQRS in Microservices

The combination of Event Sourcing and CQRS offers several advantages:

1. Historical Transparency
2. Flexibility in Query Optimization
3. Scalability and Performance
4. Resilience and Fault Tolerance
5. Support for Complex Domains

DDD

Domain-driven design (DDD) focuses on modeling software to match the domain or subject area that the software is intended for. Learn more

Why Choose DDD?

1. Clarity of Business Logic
2. Improved Communication
3. Flexibility & Scalability
4. Quality Software

Test

Unit Test

Conduct testing with NSubstitute for MOQ.

Mutation Test

To evaluate the quality of existing software tests, mutation testing with Stryker is integrated into the project.

Docker and Docker Compose

Navigate to the 'docker' folder to access the Docker Compose file, facilitating the deployment of your persistence layer.

Useful Links

Rancher Desktop: A free and commercial tool for Docker and/or Kubernetes in a local environment.