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· One min read

Starting as a fresher in Azure can be difficult because you don't have any previous knowledge regarding Azure and the services that it offers. If you are new to Azure and exploring on azure portal, One of the tips that I wanted to share today with azure enthusiasts is that you can access the learn Modules while you are in Azure Portal. You can navigate to the service that you want to create and navigate to the links provided next to each service, here is a view,

Hope this helps!

· 5 min read

Overview:

Are you hearing the word Devspaces for the first time?. Let me put this way, Imagine a developer having to deal with a large application which has chunks of Microservices and want to get some functionality done?. There will be many risks and one of them would be dealing with right environments. As we know the best way to counter this issue within a team would be to containerize and host it on cloud. Which will let the developer to work on the particular feature and debug the container without creating the environment locally. That is what exactly Azure Dev Spaces does.

What is Devspaces?

Devspaces allows you to build, test and run code inside any Kubernetes cluster. With a DevSpace, you run everything remotely inside pods running on top of a Kubernetes cluster. Additionally, the DevSpace CLI takes care things automatically such building and pushing images for you when you make changes to your Dockerfile. If you are making a source code change, the DevSpace CLI does not require you to rebuild and redeploy.

It rather syncs your locally edited source to straight to the containers running inside Kubernetes.  This makes you to edit locally but compile and run everything remotely inside Kubernetes and still use modern development features such as hot reloading. Azure Dev Spaces supports development with a minimum development machine setup. Developers can live debug on Azure Kubernetes Services (AKS) with development tools like Visual Studio, Visual Studio Code or Command Line.

With the recent announcement of Bridge To Kubernetes GA, Azure Dev Spaces will be retired on October 31, 2023. Developers should move to using Bridge to Kubernetes, a client developer tool.

What is Bridge to Kubernetes?

It was formerly called as Local Process with Kubernetes. Bridge to Kubernetes is an iterative development tool offered in Visual Studio and VS Code through extensions that you can pick up in the marketplace. IT allows developers to write, test and debug microservice code on their development workstations while consuming dependencies and inheriting existing configuration from a Kubernetes environment. There are lot of different tools and methods for solving these kind of challenges when you are working on a single micro-service in the context of a larger application. Those different methods and tools into three main types .There's the local, remote and hybrid approach as shown in the image below

Development Approaches

If you look at the above picture, developers are shifting from Local development methods to hybrid methods which offers the best way to deal with building applications to the cloud with containers/kuberentes. With Hybrid approach, it allows developers to write code on their development workstation, but also allow them to connect to external dependencies that are running in some remote environment. So it actually fulfilling all those external dependencies by connecting them. Let's say if you are running your application on Kubernetes on Azure, you can connect all the dependencies from your local environment and have the whole end-to-end workflow.

Bridge to Kubernetes Scenario

Consider the above scenario in the diagram, Assuming that i am working on a Microservice that deals with Products and the other Microservices which are developed using different stack are deployed on Kubernetes cluster on Azure. If i want to connect to any or multiple microservices and run some integration tests in my local environment Bridge to Kubernetes will help to achieve the requirement. Following are some of the Key features that Bridge to Kubernetes offers similar to Devspaces,

Accelerating and Simplifying Microservice Development

It basically eliminates the need to manually push code, configure and compile external dependencies on your development environment so that you can focus on code without worrying about other factors.

Easy Debugging Code

It lets you to run your usual debug profile with the added kuberentes cluster configuration. It allows developers to debug code in the way they want would while taking advantage of the speed and flexibility of local debugging.

Developing and Testing End-to-End

One of the important feature is the Integration testing during development time. Select an existing service in the cluster to route to your development machine where an instance of that service is running locally. Developers can initiate request through the frontend of the application running in Kubernetes and it will route between services running in the cluster until the service you specified to redirect is called same as how you would do debugging by adding a breakpoint in your code.

How to get started with Bridge to Kubernetes?

You can Start debugging your Kubernetes applications today using Bridge to Kubernetes.You need to download the extensions from the Visual Studio and VS Code marketplaces.

Bridge to Kubernetes VSCode extension

If you would like to explore more with a sample application follow the example given on Use Bridge to Kubernetes . Also kindly note the Bridge to Kubernetes collects usage data and sends it to Microsoft to help improve our products and services.

Start using Bridge to kuberentes and deploy things to production even faster than before! Cheers!

· 11 min read

Overview:

This year I've started focusing deeply on the areas around App Modernization with various cloud native offerings with different cloud vendors. One of my main focuses has been Kuberentes and how it can help organizations to design scalable applications to cater their needs. Scaling is one of the interesting concepts on Kuberentes and a very important subject to look at. This post will help you to understand the basics of the scalability aspects in Kuberentes and how you can use Event driven Applications with Kubernetes in detail.

Scaling Kubernetes

In general, Kuberentes provides two ways to scale your applications with the capabilities such as,

Cluster Scaling - It Enables users to add and remove nodes to provide more resources to run on. This is applicable to scale in an infrastructure level

Application Scaling - It can be achieved based on how your applications are running by changing the characteristics of underlying pods. Either by adding more copies or by changing the resources available to run same as how you do with services like App service on Azure.

Cluster Autoscaler : The first way of scaling can be achieved with Cluster Autoscaler. It is a tool enables automatically scaling the cluster. Most of the cloud vendors have this capability which automatically add nodes that user don't have to take care of adding more nodes. It basically add nodes when the capacity demand is there and remove nodes when they are no longer needed. I have widely used the Autoscaler with Microsoft Azure Kubernetes Service which allows you to start scaling your AKS cluster.

Event Driven Autoscaling with Kubernetes :

Necessity:

Event-driven applications are a key pattern for cloud-native applications. Event-driven is at the core of many growing trends, including Serverless compute like Azure Functions. There are so many scenarios where Kubernetes with Azure functions can be used in order to serve your applications with minimized cost.

  • Hybrid Solutions, Which needs some data to be processed on their environment
  • Applications with some specific requirements of Memory and GPUs
  • Applications which are already running on Kubernetes, so that you can leverage existing investments

Example Scenario:

Customer Scenario

In this example, lets consider a retail customer like eBay. For a retail customers who processing millions of orders and having a hybrid environment. If the customer does a lot of processing on the data center using things like Kubernetes and at some point they push those data to the cloud using eventhub or transform their data and put in the right place etc. What if the customer is getting sudden spike on a certain day like "Black Friday" and need to make sure that the compute can scale rapidly and also wanted to make sure that the orders are processed in the correct manner.

Arrival of KEDA :

Since Azure functions is open sourced  so one of the things that azure functions team working with and talking to the community some partners like Redhat is how can they  start to bring more of these experiences to that other side to where you don't want to have lock-in to a specific cloud vendor and to run these service workloads anywhere could be on other clouds. Kubernetes Event-Driven Autoscaling (KEDA) which is a Microsoft & Red Hat partnership that would make auto scaling Kubernetes workloads a lot easier. With Azure Functions, you write code which is triggered when a certain trigger occurs and they handle the scaling for you, but you have no control over it. With combining Kubernetes you have to tell it how to scale your application so it's fully up to you! On May 6th, 2019 Microsoft announced that they have partnered with Red Hat to build Kubernetes-based event-driven autoscaling (KEDA) which brings both worlds closer together.

What is Kubernetes-based event driven autoscaling (KEDA) ?

KEDA provides an autoscaling infrastructure that allows you to very easily autoscale your applications based on your criteria. Nothing to process? No problem, KEDA will scale your app back to 0 instances unless there is work to do.

How does it work?

KEDA comes with a set of core components to provide the scaling infrastructure:

  • Controller to coordinate all the work and watch for new ScaledObjects
  • Kubernetes Custom Metric Server
  • A set of scalers which allow you to scale on external services

Kubernetes-based event-driven autoscaling (KEDA) Architecture

The controller is the heart of KEDA and is handling the following responsibilities :

  1. Watching for new ScaledObjects
  2. Ensuring that deployments where no events occur, scale back to 0 nodes. Once events occur, it makes sure that it scales from 0 to n.

How it Differs from Kubernetes ?

"Default Kubernetes Scaling is not well suited for Event Driven Applications"

By default kuberentes is not very well suited for event-driven scaling and that's because by default kuberentes can really only do resource based scaling looking at CPU and Memory.

What K8s can do?What K8s can't do?
Scheduling of containersInvoke code based on external events
Capacity managementScale based on external metrics

When do we need KEDA!

Sample Deployment :

As an application admin, you can deploy ScaledObject resources in your cluster which define the scaling rules for your application based on a given trigger.

These triggers are also referred to as “Scalers”. They provide a catalog of supported sources on which you can autoscale and provide the required custom metric feeds to scale on. This allows KEDA to very easily support new scale sources by adding an individual scaler for that service. Let’s have a look at a ScaledObject that automatically scales based on Service Bus Queue depth.

Scaled Object Deployment with Kafka using KEDA

As you see in the file, All it contains is that whatever deployment that you are going to scale it goes under scaletargetreference. You can also set some metadata such as how frequently to pull for events that you can control. Metadata such as Minimums and maximums and then you can define the event source in this case it is mention as Kafka, you can also mention things like service bus etc. Once the deployment is applied on kuberentes you can see that it will identify that scaled objects. Based on the events on the eventssources it is going to identify and scale it automatically. HPA does the autoscaling.

Run Azure Functions Anywhere

With the production release of KEDA back in 2019, you can now safely run your azure function apps on Kubernetes and its recommended by the product group. This allows the users to build serverless applications once re-use them on other infrastructures as well. Let's see How to build an application that supports the above scenario discussed.

PreRequisities :

This article requires you to have the following tools & services:

  • Azure CLI
  • Azure Subscription
  • .NET Core 3.1
  • Kubernetes cluster with KEDA installed
  • Function Tools
  • Visual Studio Code
  • Docker Desktop

Step 1: Create a Resource Group

First step is to create the resource group using which all the necessary resources will be grouped together!

https://gist.github.com/sajeetharan/839847fe89b1b3ea90679ae7d2782d6e.jsView this gist on GitHubCreate Resource Group Named "rgKeda" in "Southeastasia" region

Step 2 : Create a Storage Account

Let's create a Storage Account to store the order messages, You can do this by the command,

https://gist.github.com/sajeetharan/fc885f9ddb7916c015ff470823f1c8f0.jsView this gist on GitHubCreate Storage Account Named "sakeda"

Step 3 : Create a Queue in Service Bus

Next step is to create the queue to store the orders under the namespace "sbqOrders"

https://gist.github.com/sajeetharan/685feca2dbc8e591a759a8da4b36c491.jsView this gist on GitHubCreate Storage Queue to store the order messages

Step 4 : Create Azure Kubernetes Service

To showcase the feature of event driven scaling with the kubernetes let's create a Kubernetes cluster on Azure with two nodes.

https://gist.github.com/sajeetharan/94812cad484f0de46490e5069e08a8c6.jsView this gist on GitHub

Once these resources are created you can double check it by navigating to azure portal and opening the resource group.

Resources for the Kubernetes Event Driven Autoscaling

Now we have created all the necessary resources. In the above step you can see that we have create two nodes but have not deployed anything to those nodes, but in real scenarios that nodes can contain some applications already running on Kubernetes.

Step 5 : Create Azure Function to Process the Queue Message

Let's create an Azure function to process these queue messages, you can navigate to the folder and create a containerized function as follows,

https://gist.github.com/sajeetharan/569c6ef142d5b64ce5a5c3fb134e920d.jsView this gist on GitHubCreate a containerized Function

Make sure to select the preferred language and the app will be created as follows,

lets create the new function as ,

https://gist.github.com/sajeetharan/d24f16c79111688f5c2167bf8947856f.jsView this gist on GitHubCreate new function

In this case we need to create a function to get triggered when there is a new message in the queue, so select the Trigger as QueueTrigger from the template,

Select Queue Trigger

and give a function name as follows,

Create Function with QueueTrigger template

Open the function in vscode and configure the storage queue connection string in the local.appsettings.json, the connection string can be obtained from the Azure portal in Storage Account "saKeda" -> Queues -> Access Keys

{
"IsEncrypted": false,
"Values": {
"AzureWebJobsStorage": "UseDevelopmentStorage=true",
"FUNCTIONS_WORKER_RUNTIME": "dotnet",
"StorageConnection": "DefaultEndpointsProtocol=https;AccountName=sakeda;AccountKey=uPmdavPQ5DOYD3A5sJbeODP5He9OBv3sYpmlGj6fs7mQYZsk7P/ShP6Go9u+waBBean+1PJwjUEkGVnRsHf/rNg==;EndpointSuffix=core.windows.net"
}
}

Whole function code can be viewed from here.

Step 6 : Build the function and Enable Keda on AKS cluster

As we have everything ready, let's build the function with the below command,

 docker build -t processorder:v1 .

As the next step , we need to enable KEDA on the Azure Kubernetes Cluster. This is similar on any Kubernetes environment which can be achieved by below,

https://gist.github.com/sajeetharan/76b6529d6adc0235f50921d0ba6c0519.jsView this gist on GitHub

Keda.yaml is the configuration file which has all details. In our case we define that we want to use the queue trigger and what our criteria is. For our scenario we’d like to scale out if there are 5 or more messages in the orders queue with a maximum of 10 concurrent replicas which is defined via maxReplicaCount. Let's apply the yaml file on the cluster.

kubectl apply -f keda.yaml --namespace="kube-system"

Step 7 : Deploy the container as Azure function extended with AKS

Final step is to deploy the function to kubernetes environment with the following command,

https://gist.github.com/sajeetharan/fc52f2e6a686bca16acc190fee2137c0.jsView this gist on GitHub

Make sure that you are tagging the correct registry name , here i am using my docker registry, instead you can consider using Azure Container Registry as well.

Let's view the kubernetes cluster. if you have install the kubernetes extension you can easily view the status of the cluster using vscode.

Step 8 : Publish messages to the Queue

Inorder to test the scaling of Azure function with KEDA, i created a sample console application which pushes the messages to the queue we created. And the code looks as follows,

using Microsoft.WindowsAzure.Storage;
using Microsoft.WindowsAzure.Storage.Queue;
using System;
using System.Threading;
using System.Threading.Tasks;

namespace Serverless
{
class Program
{
static async Task Main(string[] args)
{
CloudStorageAccount storageClient = CloudStorageAccount.Parse("connection string");
CloudQueueClient queueClient = storageClient.CreateCloudQueueClient();

CloudQueue queue = queueClient.GetQueueReference("sqkeda");
for (int i = 0; i < 100000000; i++)
{
await queue.AddMessageAsync(new CloudQueueMessage("Hello KEDA , See the magic!"));
}

}
}
}

As the messages are getting inserted to the queue, the number of replicas gets increased which you can see from the image below.

Once all the messages have been processed KEDA will scale the deployment back to 0 pod instances. Overall process is simplified in the diagram below,

Serverless eventing with Kubernetes

Conclusion :

We have easily deployed a .NET Core 3.1 Function on Kubernetes which was processing messages from Storage Queue. Once we’ve deployed a ScaledObject for our Kubernetes deployment it started scaling the pods out and in according to the queue depth. This makes the application very easily plug in autoscaling with existing application without making any changes!

This makes Kubernetes-based event-driven autoscaling (KEDA) a great addition to the autoscaling toolchain, certainly for Azure customers and ISVs who are building solutions. Hope this was useful in someway! Cheers!

· 2 min read

Since the acquisition by Microsoft, Github been so much better! They have added so many new features, made mobile app. GitHub recently made lot of improvements on the UI aspects including adding a twitter handle to your profile. Also introduced a special feature for developers, that allows you to showcase yourself by pinning a README.md containing information about you, your work, portfolio and anything else on your GitHub profile.

In this post, I'll show you how to create a rocking Github profile to showcase your skills when someone visits your profile

Prerequisites

  • A GitHub account
  • Basic markdown knowledge
  • Expertise on Making Gifs would be an added advantage

Step 1 :

Create a new ✨special✨ repository with your username. The special repository is case sensitive, ensure to use the same case as your account's username.

Creating special repository

Step 2 :

Click on the checkbox: "Initialize this repository with a README". This will create a README.md file inside your <Username>/<Username> repository, where you will be adding the details.

Template Github Profile

If you are not sure what to add, you also get a free template out of the box, cool right?

Here's my own finished rocking profile page from the special repository:

My Github Profile

This is definitely a great feature for developers to expose their skills and also to showcase to recruiters, followers etc. I would ask everyone to get creative and showcase everything about yourself to your frollowers

Done with your special repository ? Drop a link to your GitHub account in the comments and let's see how amazing yours look. ✌🏾 Cheers!

· One min read

One of the most repeated question that i came across on stackoverflow on the tag #Cosmosdb is that how to resolve the error "The partition key supplied in x-ms-partitionkey header has fewer components than defined in the the collection"

This error could occur when you are attempting to get a Document from Cosmosdb using the REST API or using SDK. If you are using using a partitioned Collection and therefore you need to add the "x-ms-documentdb-partitionkey" header. Even after adding the header if you get the error you can fix it by the following methods,

Partition key must be specified as an array (with a single element). For example:

in C#

  requestMessage.Headers.Add("x-ms-documentdb-partitionkey", " [ \"" + partitionKey + "\" ] ");

In Javascript

headers['x-ms-documentdb-partitionkey'] = JSON.stringify([pkey]);

Partition key for a partitioned collection is actually the path to a property in Cosmosdb. Thus you would need to specify it in the following format:/{path to property name} e.g. /abc

Hope this helps someone out there who is struggling to fix this issue!