Develop and build ASP.NET Core applications to run on Kubernetes with Draft

You start developing an ASP.NET Core application to run it in Kubernetes and suddenly you find yourself creating a docker file, building an image, pushing the image to a registry, creating both a deployment and a service definition for Kubernetes and you wonder if there is a tool out there to help you streamline the whole process.

Meet Draft a tool that will not only help you create the artifacts needed to build and run applications in Kubernetes but to also build the container image and deploy it.

Prerequisites:

A Kubernetes cluster and the kubectl CLI tool
Installation of Helm on your Kubernetes cluster
A Container Registry

Install and Configure Draft

To install Draft I run the following command:

1cinst -y draft

Then configure it:

1draft config set registry <registry full name>

Be sure to log on to the Container Registry:

1docker login <registry full name>

or if working with Azure Container Registry:

1az acr login --name <acrName>

Create and prepare the application

Creat an ASP.NET Core MVC application and create the artifacts with Draft:

1dotnet new mvc
2draft create --pack=csharp -a mvcdraft

Note that I’ve specified two parameters:

pack to tell draft that we are using C# as the language.
a to specify the name of the Helm release we will run on Kubernetes

Deploy and test your application

Run the following command to build the container image and then deploy the application to Kubernetes:

1draft up

The first time you run the command it will take a while. The output should look similar to this:

1Draft Up Started: 'netcoredraft': 01CWKAZ79WR6W66PHHR2AFRSGC
2netcoredraft: Building Docker Image: SUCCESS ⚓  (1.0008s)
3netcoredraft: Pushing Docker Image: SUCCESS ⚓  (3.2891s)
4netcoredraft: Releasing Application: SUCCESS ⚓  (2.7629s)
5Inspect the logs with `draft logs 01CWKAZ79WR6W66PHHR2AFRSGC`

To test the application run:

1draft connect

The output should look similar to:

1Connect to netcoredraft:80 on localhost:50998
2[netcoredraft]:       No XML encryptor configured. Key {ea9dac08-e7af-468c-9e00-cbe38ab40fa8} may be persisted to storage in unencrypted form.
3[netcoredraft]: Hosting environment: Production
4[netcoredraft]: Content root path: /app
5[netcoredraft]: Now listening on: http://[::]:80
6[netcoredraft]: Application started. Press Ctrl+C to shut down.