DEV Community

Hussein Mahdi
Hussein Mahdi

Posted on

πŸ”„ Simplified Approach: Asynchronous Request-Reply

In modern app development, when clients need to interact with remote APIs for business logic or services, the Asynchronous Request-Reply pattern shines. Here's how it works :

  • Client Makes Request: The client (like a web browser) sends a request to the backend API over HTTP(S).

  • Backend Acknowledges: Upon receiving the request, the backend immediately acknowledges it, letting the client know it's been received.

  • Backend Processes Asynchronously: Instead of making the client wait, the backend processes the request asynchronously. This means it can handle multiple tasks simultaneously without blocking.

  • Immediate Response: While the backend works, the client gets an immediate response, indicating the request has been accepted.

  • Notification of Completion: Once processing is complete, the backend notifies the client, providing the result or status update.
    Benefits:

  • Improved Responsiveness: Clients get immediate feedback, making interactions smoother.

  • Efficient Resource Utilization: Asynchronous processing allows the backend to handle tasks concurrently, optimizing resource usage.

  • Scalability: The system can handle more requests without sacrificing performance.

This approach simplifies communication between clients and servers, making applications more responsive and scalable.

Image description

βœ… When to Use This Pattern:

  • Client-Side Code: Ideal for client-side applications like browsers where setting up callback endpoints or long-running connections is complex.

  • Service Calls Over HTTP: Useful when only HTTP protocol is available and firewall restrictions prevent callback firing on the client-side.

  • Integration with Legacy Architectures: When integrating with older systems that lack support for modern callback technologies such as WebSockets or webhooks.

❌ When Not to Use This Pattern:

  • Alternative Services Available: If there's a service designed for asynchronous notifications like Azure Event Grid, it may be a better fit.

  • Real-Time Streaming Required: Not suitable when real-time streaming responses are needed.

  • Many Results with Low Latency: For scenarios where the client needs to collect numerous results with low latency, consider a service bus pattern instead.

  • Persistent Network Connections Supported: If server-side persistent network connections like WebSockets or SignalR are feasible, they can be used for real-time result notifications.

  • Network Design Constraints: If network design allows for opening ports to receive asynchronous callbacks or webhooks, consider those options.

  • Using the Asynchronous Request-Reply pattern can simplify communication in certain scenarios, but it's essential to consider alternative solutions when they better align with specific requirements or constraints.


More Details :

1- https://learn.microsoft.com/en-us/azure/architecture/patterns/async-request-reply?WT.mc_id=DX-MVP-5004571

2- https://youtu.be/LCbR58sCmvQ?si=qrSA_2zlzG0cV9_i

Top comments (0)