Book Image

Practical Microservices with Dapr and .NET - Second Edition

By : Davide Bedin
Book Image

Practical Microservices with Dapr and .NET - Second Edition

By: Davide Bedin

Overview of this book

This second edition will help you get to grips with microservice architectures and how to manage application complexities with Dapr in no time. You'll understand how Dapr simplifies development while allowing you to work with multiple languages and platforms. Following a C# sample, you'll understand how Dapr's runtime, building blocks, and software development kits (SDKs) help you to simplify the creation of resilient and portable microservices. Dapr provides an event-driven runtime that supports the essential features you need for building microservices, including service invocation, state management, and publish/subscribe messaging. You'll explore all of those in addition to various other advanced features with this practical guide to learning Dapr. With a focus on deploying the Dapr sample application to an Azure Kubernetes Service cluster and to the Azure Container Apps serverless platform, you’ll see how to expose the Dapr application with NGINX, YARP, and Azure API Management. By the end of this book, you'll be able to write microservices easily by implementing industry best practices to solve problems related to distributed systems.
Table of Contents (20 chapters)
1
Part 1: Introduction to Dapr
5
Part 2: Building Microservices with Dapr
11
Part 3: Deploying and Scaling Dapr Solutions

Autoscaling with KEDA

So far, we’ve learned that the HPA is triggered by the CPU and memory metrics of the Pods in a Deployment.

Kubernetes-Based Event-Driven Autoscaling (KEDA) is a Cloud-Native Computing Foundation (CNCF) project, with the objective of extending the capabilities of the Kubernetes HPA so that it reacts to the metrics of resources that are external to the Kubernetes cluster.

You can learn more about KEDA (https://keda.sh/) in the context of Dapr at https://docs.dapr.io/developing-applications/integrations/autoscale-keda/.

Considering the vast adoption of the publish/subscribe Dapr building block in our example, it would be smart to increase (and decrease) the number of Pods based on the messages accumulating in the underlying messaging system, which is Azure Service Bus in our case. If the number of enqueued messages grows, we could add more Pods so that Dapr dequeues the messages and our ASP.NET code processes the requests.

In more general terms...