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· 8 min read

Overview

Are you are .Net developer interested in building Microservice based applications to the Cloud?. Recently i gave a talk about announcements on DotNet ecosystem and building Cloud Native applcitions with Tye and i decided to write on the same topic . Tye is an amazing project from Microsoft to ease the development, deployment with two fundamental cloud native technologies such as Docker and Kubernetes. If you have been deploying Applications in production using containers, you must be already aware of how complex steps you need to make in order to get your application running. I have worked on multiple projects where I have to run many modules as dependencies at the same time, even though I was only  working on one of them. There has always been a requirement for a tool to start, deploy applications with a  simple command to your desired environment without spending much time on creating docker files, configurations etc.

What is Project Tye?

Tye is an experimental developer tool from the .NET team at Microsoft that makes developing, testing, and deploying microservices and distributed applications easier. It comprises a local orhestrator to assist the developers to develop microservices, deploy them to kubernetes with minimal configuration and steps.

  • Service discovery via configuration conventions makes Developers to expose their API with proper documentation
  • Add dependencies (Redis, SQL Server, etc.) without writing docker files
  • Run and debug locally using containers and Kubernetes
  • Local dashboard for metrics, logging, debugging
  • Automatically dockerize and deploy to Azure Kubernetes Service

What I like really like about Project Tye is that it has a very small footprint and it is so simple to get started with after spending so many years with docker and K8s. It offers the following capabilities,

Getting Started

Let's see how to get started with project Tye. You need to have the following Prerequisites in order to run the following application successfully.

  • Azure Subscription (Free Trial)
  • Dotnet SDK latest
  • Visual Studio / Visual Studio Code
  • Docker/Kubernetes Extension VSCode ( Optional)

You can install Project Tye as a global .NET tool. In order to install the utility, you need to run the following command in your terminal

dotnet tool install -g Microsoft.Tye --version "0.2.0-alpha.20258.3"

To verify that Tye was installed properly you can run the following command that should output the current version installed:

> tye --version

Create a Simple Application

This section will demonstrate how to use Tye to run multi-project application.

Step 1 : Make a new folder named dotnetconfApp

mkdir dotnetconfApp
cd dotnetconfApp

Step 2 : Create a frontend project with Razor

dotnet new razor -n frontend

Step 3 : To run the frond end project, execute the following command

tye run frontend

As you could see above tye will do two things: start the frontend application and run a dashboard. Navigate to http://localhost:8000 to see the dashboard running.

The dashboard should show the frontend application running.

  • The Logs column has a link to view the streaming logs for the service.
  • the Bindings column has links to the listening URLs of the service.

Project Tye Dashboard

Add Multiple Projects

Step 1 : Let's go ahead and add a Web API to fetch the data for the front end application. If you haven't already, stop the existing tye run command using Ctrl + C. Create a backend API that the frontend will call inside of the microservices/ folder.

dotnet new webapi -n backend

Step 2 : Create a solution file and add both projects

dotnet new sln
dotnet sln add frontend backend

You should have a solution called dotnetconfapp.sln that references the frontend and backend projects.

Step 3: Run the multiple projects with tye . Execute the following command within the solution folder,

tye run

The dashboard should show both the frontend and backend services. You can navigate to both of them through either the dashboard of the url outputted by tye run.

Make the Communication between the frontend and backend

As you see above, we have both the backend and frontend applications running, let's make them communicate. By default, tye enables service discovery by injecting environment variables with a specific naming convention.

Step 1: Open the solution folder with VSCode or Visual Studio

Step 2 : As we need to fetch and bind the data from the sample WebApi , lets add a Contract named WeatherForecast.cs to the frontend project and it should match the contract that exist in the backend project WeatherForecast.cs

using System;

namespace frontend
{
public class WeatherForecast
{
public DateTime Date { get; set; }

public int TemperatureC { get; set; }

public int TemperatureF => 32 + (int)(TemperatureC / 0.5556);

public string Summary { get; set; }
}
}

Step 3: Add a file WeatherClient.cs to the frontend project with the following contents:

using System.Net.Http;
using System.Text.Json;
using System.Threading.Tasks;

namespace frontend
{
public class WeatherClient
{
private readonly JsonSerializerOptions options = new JsonSerializerOptions()
{
PropertyNameCaseInsensitive = true,
PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
};

private readonly HttpClient client;

public WeatherClient(HttpClient client)
{
this.client = client;
}

public async Task<WeatherForecast[]> GetWeatherAsync()
{
var responseMessage = await this.client.GetAsync("/weatherforecast");
var stream = await responseMessage.Content.ReadAsStreamAsync();
return await JsonSerializer.DeserializeAsync<WeatherForecast[]>(stream, options);
}
}
}

Step 4 : Add a reference to the Microsoft.Tye.Extensions.Configuration package to the frontend project

dotnet add frontend/frontend.csproj package Microsoft.Tye.Extensions.Configuration  --version "0.4.0-*"

Step 5 : Register  this client in frontend by adding the following to the existing ConfigureServices method to the existing Startup.cs file:

...
public void ConfigureServices(IServiceCollection services)
{
services.AddRazorPages();
/** Add the following to wire the client to the backend **/
services.AddHttpClient<WeatherClient>(client =>
{
client.BaseAddress = Configuration.GetServiceUri("backend");
});
/** End added code **/
}
...

This will connect the WeatherClient to use the correct URL for the backend service.

Step 6 : Add a Forecasts property to the Index page model under Pages\Index.cshtml.cs in the frontend project.

...
public WeatherForecast[] Forecasts { get; set; }
...

Change the OnGet method to take the WeatherClient to call the backend service and store the result in the Forecasts property:

...
public async Task OnGet([FromServices]WeatherClient client)
{
Forecasts = await client.GetWeatherAsync();
}
...

Step 7 : Change the Index.cshtml razor view to render the Forecasts property in the razor page:

@page
@model IndexModel
@{
ViewData["Title"] = "Home page";
}

<div class="text-center">
<h1 class="display-4">Welcome</h1>
<p>Learn about <a href="https://docs.microsoft.com/aspnet/core">building Web apps with ASP.NET Core</a>.</p>
</div>

Weather Forecast:

<table class="table">
<thead>
<tr>
<th>Date</th>
<th>Temp. (C)</th>
<th>Temp. (F)</th>
<th>Summary</th>
</tr>
</thead>
<tbody>
@foreach (var forecast in @Model.Forecasts)
{
<tr>
<td>@forecast.Date.ToShortDateString()</td>
<td>@forecast.TemperatureC</td>
<td>@forecast.TemperatureF</td>
<td>@forecast.Summary</td>
</tr>
}
</tbody>
</table>

Step 8 : Run the project with tye run and the frontend service should be able to successfully call the backend service!

When you visit the frontend service you should see a table of weather data. This data was produced randomly in the backend service. Since you are seeing the data in a web UI in the frontend means that the services are able to communicate.

If you are getting any issues with the self signed scertifications, you need to run the below commands,

dotnet dev-certs https --clean
dotnet dev-certs https --trust

Let's deploy to Kubernetes

Step 1 : Provision the Kubernetes Cluster, since we will be using Azure Kubernetes Service , you can provision it by either CLI or using Azure Portal

Step 2 : Let's authenticate and get the required credentials

az aks get-credentials --resource-group dotnetconfsl-rg  --name dotnetconf

Step 3: You need to have either Docker registry or Azure container registry created where docker images of the frontend and backend will be pushed.

Step 4 : Now everything is ready do easy deploy the solution. Navigate to the solution folder and execute following:

tye deploy --interactive

You will be prompted to enter the Container Registry (ex: 'example.azurecr.io' for Azure or 'example' for dockerhub) where the Kubernetes service is installed.

The deployment process has built the docker container and pushed repositories to my registry:

Test the application

If you are using VScode with the Kubernetes extension installed, once you authenticate to Azure using Azure extension, you will be able to navigate to the cluster and click on Workloads -> Pods -> Right Click Get

You can also explore the running pods from the Azure portal or using Cloudshell as well. You'll have two services in addition to the built-in kubernetes service.

You can visit the frontend application by port forwarding to the frontend service.

kubectl port-forward svc/frontend 5000:80

Now navigate to http://localhost:5000 to view the frontend application working on Kubernetes. You should see the list of weather forecasts just like when you were running locally.

Some important Notes:

⚠️ Currently tye does not provide a way to expose pods/services created to the public internet.

⚠️ Currently tye does not automatically enable TLS within the cluster, and so communication takes place over HTTP instead of HTTPS.

Conclusion:

In this post I explained how easy it is to get started with Project Tye and How to run a simple web application. You can certainly do the same adding an external dependency like SQL server or Redis cache without creating docker files manually. In short, Tye simplifies the multiple gestures for all the services within an application to a single command. Even though Project Tye is an experimental tool , you can watch out for more features around service discovery, diagnostics , observability, configuration and logging when it comes to building cloud native applications with Microservices. Certainly it's a great addition to the tooling what .Net ecosystem provides and hope you will consider exploring it more. Cheers!

· 7 min read

Quarantine, self isolation , social distancing for the past one month, I’m living with these words. While most of us are investing this time to learn new technologies/tools. I challenged myself to skill up myself and have deep knowledge on certain services on Azure.

Kubernetes provides a uniform way of managing containers. Its aim is to remove the complexity of deciding where applications should be scheduled to run, how to locate them, how to ensure they are running, autoscale or deploy. Azure Kubernetes is a service on Azure that help Customer achieve their business goals, by providing a layer of automation on top of their infrastructure. Going towards the technical features, Azure Kubernetes has a lot to offer, but at the end of the day, is a great platform for saving money or growing faster.

Azure Kubernetes service offers great set for microservice architectures. If your application needs to start hundreds of containers quickly or will terminate them just as quickly and to have full control of those services, AKS is a great option. There are other scenarios such as Bigdata, IOT scenarios you would consider AKS as a preferred choice. In this post i will explain how to easily setup your application running on AKS cluster in 10 minutes with CI/CD pipelines.

PreRequisities:

You will need to have an Azure Subscription. If you do not have an Azure subscription you can simply create one with free trial.

How to build & Deploy the application:

If you are a beginner with Azure Kubernetes Service, Azure Devops is the best place that you need to look in order to understand how an Application is deployed on Azure Kubernetes. The Azure DevOps Project simplifies the setup of an entire continuous integration (CI) and continuous delivery (CD) pipeline to Azure with Azure DevOps. Cool thing is that, you can start with existing code or use one of the provided sample applications. It enables you to quickly deploy that application to various Azure services such as Virtual Machines, App Service, Azure Kubernetes Services (AKS), Azure SQL Database, and Azure Service Fabric.

Lets Deploy an Node.js App to Azure Kubernetes Service :

Navigate to Azure Portal and search for Azure Devops Project in the market place/search bar.

Azure Devops Project

Let's go ahead and add a new project.

Add new Azure Devops Project

Azure Devops project enables developers to launch an app withany Azure App Service in just a few quick steps, providing everything needed to develop, deploy and monitor an app. Create a DevOps Project, and it provisions all the Azure resources and provides a Git code repository, Application Insights integration and a continuous delivery pipeline setup for deployment to Azure. The DevOps Project dashboard lets you monitor code commits, builds and deployments from a single view in the Azure portal. How cool is that ?

With the help of Azure DevOps Projects, you can build an Azure application, on an Azure service, in quick time. You also get automatic full CI/CD pipeline integration, built-in monitoring and deployment to the platform of your choice. Azure Devops Project supports almost all the latest languages out there in practice such as .Net,Java,Node.js,PHP,Python and Go.

Next step is to select the Language you want to have the application on, I will go ahead and choose Nodejs as my application language. But you could choose any language that you want to test.

Create Node.js Devops Project

Once you select the language, next step is to select the framework in which you want the application to be based on , For example, if you choose Python it could be based on Flask,Django etc. Similarly you have the flexibility to choose the framework once you decide the language. In this case i will go ahead and choose express.

Select the Framework

Next step is the critical part of the process, This is the step that defines which service you would be using to deploy the app. You can Run your application on Windows or Linux. Simply deploy to Azure Web App, Virtual Machine, Service Fabric or choose Azure Kubernetes Service for your application. Each of those option provides deployment in an elegant and fast way. In this case, we will deploy the application to Azure Kubernetes service.

Azure Kubernetes Service to Deploy

Once you are done with the above step, final step is passing the configuration details for the Kubernetes cluster on AKS as follows,

Most of the settings are self explanatory , you can change the size of underlying VMs based on your requirement. The default number of nodes for your cluster comes as 3 , if you need to make changes to your cluster and the container registry settings click on Additional Settings. Here you can configure the Kubernetes version, Node count, App Insights and resource group location. The HTTP application routing solution makes it easy to access applications that are deployed to your Azure Kubernetes Service (AKS) cluster. In this case we will disable it.

Additional Settings AKS configuration

Container registry is needed as your images needs to be pushed to them. Once you're good with all settings, click ok and done!. You will see a notification box as below.

K8s cluster, Container Registtry, CI/CD pipelines are created

Once everything is created you will be redirected to a Dashboard page as below.

Resources in page

The four stages involved are:

  1. Azure Kubernetes Cluser: Created and configured your Azure Kubernetes Cluster and application endpoint.
  2. Azure Container Registry : Created and application image is pushed to the container registry.
  3. Repository: Created a distributed Git repository and checked in sample code.
  4. CI/CD Pipeline: Seamlessly connected with the Azure Devops collaboration solution allows you to plan, test, release and monitor your solutions.
  5. Application Insights:  Created and configured your Application Insights telemetry which enables active monitoring and learning to proactively detect issues and continuously analyze and test hypotheses without code.

You can see all the resources created on Azure under the resource group

Resource Group with All resources

When you click on the Kuberentes cluster, you can see the Kubernetes related resources such as dashboard logs etc.

Kubernetes cluster resources

And if you navigate to the blade you can see the settings such as Enabling Dev spaces , Kubernetes version, Application Insights etc.

On the Azure Devops side, you will be able to see new Azure Devops project created with Dashboard, Backlog items, CI/CD pipelines etc.

Azure Devops Project with CI/CD pipelines

And when you click on the application endpoint, you would see that the application running successfully on Azure Kubernetes service.

Nodejs App on AKS

In order to verify the services and pods, you could follow the steps provided in the Azure Kubernetes dashboard configuration and when you open up the dashboard, you can see the status of each services.

Azure Kubernetes dashboard

I have spent more than 4 days in the past to configure Kubernetes to deploy my application. But Azure Devops project Simplify and speed up the DevOps process with Azure DevOps services. If you want to explore more kind of scenarios on different services on Azure its worth to explore Azure Devops Labs. I hope it makes it easier to get started with any of the deployment with Azure services. Cheers!