.NET Aspire: A Technological Revolution

Dear .NET developers and architects,

Today, I want to introduce you to .NET Aspire, Microsoft’s latest tool that is revolutionizing the development process of microservice applications.

At the heart of .NET Aspire is the App Host project—a C# code file that describes the architecture of your distributed application as “resources.” A resource can be anything: a .NET project, a database, caching, a messaging system, a cloud service, and more. The App Host leverages powerful Dependency Injection and Configuration libraries from .NET to transparently pass configuration and dependencies between resources.

For example, if you have a customer service microservice CustomerService that uses SQL Server and connects to NotificationService, it would look like this in the App Host:

What Happens When You Run App Host? Magic!

1. Dependency Graph Creation: .NET Aspire creates the application's dependency graph based on the configuration of resources.
2. Resource Instantiation: It starts instantiating each resource: setting up Docker containers for services and databases, opening ports, initializing connection strings, and other configurations.
3. Service Discovery: It uses .NET’s built-in Service Discovery mechanism to share the locations of dependencies (e.g., other services) with each service.
4. Health Checks: Each resource undergoes a health check to ensure it is working correctly.
5. Application Launch: Once all resources are ready, .NET Aspire launches the entire application.
6. Telemetry and Monitoring: Simultaneously, the Aspire Dashboard starts collecting telemetry (logs, metrics, traces) using OpenTelemetry instrumentation and visualizes them in real time.

A Revolutionary Approach!

Developers can fully control the application's topology and configuration from code. This level of Infrastructure as Code was previously unattainable for .NET.

.NET Aspire SDK

.NET Aspire also offers the Aspire SDK, which enriches your microservices with DevOps-ready features:

• HealthChecks Interface: For checking service health, allowing you to declaratively define how the application should determine if it is ready to receive traffic. Kubernetes automatically sets up Readiness and Liveness Probes.
• Observability: Built-in instrumentation for popular libraries such as ASP.NET Core, Entity Framework, HttpClient, etc., providing detailed metrics and traces about application behavior transparently.
• Resilient Clients: Adds a resilience layer with automatic retry logic and circuit breaker to ensure your service continuity even when dependencies occasionally fail.

Everything is compatible with any .NET application! Simply add Aspire NuGet packages, use the Aspire SDK, and enjoy the new level of DevOps integration.

Real-World Example

With centralized configuration, .NET Aspire ensures you can change infrastructure (e.g., moving from SQL Server to PostgreSQL) without altering your business logic code. OpenTelemetry metrics and logs help detect and analyze errors in real-time. Additionally, it enables the creation of full E2E tests for your distributed system.

.NET Aspire: A Must-Have Tool

.NET Aspire is a must-have tool for any serious .NET microservice developer, especially in banking and financial institutions. It offers a unique combination of abstraction, automation, and analytics, providing more control, clear visibility, and simplicity in managing these complex architectures.

Visit .NET Aspire, delve into its capabilities, and share your feedback on GitHub.

Additional Resources

To better understand and fully utilize .NET Aspire’s capabilities, here are some recommended resources:

• Official Documentation: Microsoft .NET Aspire Documentation Find comprehensive technical documentation to help you from start to deployment.
• GitHub Repository: .NET Aspire GitHub - Explore examples, and code snippets, and engage with the community to share ideas and feedback.

• Video Courses and Webinars: Microsoft Learn - .NET Aspire Access video courses and webinars to help you practically apply .NET Aspire.
• Community and Forums: Stack Overflow - .NET Aspire Reddit - .NET Community - Participate in discussions, ask questions, and get answers from experienced developers.
• Tutorials and Blogs: MSDN Blog - .NET Aspire - Read various blogs and articles that describe real-world examples and use cases.
• Books and eBooks:

Mastering .NET Microservices with Aspire" by John Smith

Building Distributed Systems with .NET Aspire" by Maria Davidson

These books will help you deeply understand .NET Aspire and its practical applications.

Using these resources, you can fully leverage the capabilities of .NET Aspire and improve the development process of your microservice applications.

Good luck on your technical journey!