eShopOnContainers is a comprehensive reference application for .NET microservices and container-based application architecture. It demonstrates best practices for building scalable, resilient, and maintainable distributed systems using modern technologies such as .NET, Docker, and Kubernetes.

Pros

• Provides a complete, production-ready microservices architecture example
• Implements various design patterns and best practices for distributed systems
• Offers detailed documentation and guidance for implementation
• Supports multiple deployment options, including local development, Azure, and on-premises

Cons

• Can be overwhelming for beginners due to its complexity
• Requires significant resources to run the entire system locally
• May not cover all specific use cases or industry-specific requirements
• Regular updates might be needed to keep up with rapidly evolving technologies

Code Examples

// Example of using MediatR for CQRS pattern
public class CreateOrderCommandHandler : IRequestHandler<CreateOrderCommand, bool>
{
    private readonly IOrderRepository _orderRepository;

    public CreateOrderCommandHandler(IOrderRepository orderRepository)
    {
        _orderRepository = orderRepository;
    }

    public async Task<bool> Handle(CreateOrderCommand request, CancellationToken cancellationToken)
    {
        var order = new Order(request.UserId, request.UserName, request.City, request.Street, request.State, request.Country, request.ZipCode);
        return await _orderRepository.AddAsync(order);
    }
}

// Example of using API Gateway pattern with Ocelot
public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddOcelot(Configuration);
    }

    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        app.UseOcelot().Wait();
    }
}

// Example of implementing resilience with Polly
public static class HttpClientExtensions
{
    public static IHttpClientBuilder AddRetryPolicy(this IHttpClientBuilder builder)
    {
        return builder.AddPolicyHandler(GetRetryPolicy());
    }

    private static IAsyncPolicy<HttpResponseMessage> GetRetryPolicy()
    {
        return HttpPolicyExtensions
            .HandleTransientHttpError()
            .OrResult(msg => msg.StatusCode == System.Net.HttpStatusCode.NotFound)
            .WaitAndRetryAsync(6, retryAttempt => TimeSpan.FromSeconds(Math.Pow(2, retryAttempt)));
    }
}

Getting Started

1. Clone the repository:

   git clone https://github.com/dotnet-architecture/eShopOnContainers.git
   

2. Install Docker Desktop and enable Kubernetes

3. Navigate to the src folder and run:

   docker-compose build
   docker-compose up
   

4. Access the application at http://localhost:5100 for the Web MVC app or http://localhost:5104 for the Web SPA

Note: For detailed setup instructions and deployment options, refer to the project's documentation.