Using Docker to Deploy an Image to Azure

I have always used .NET and Visual Studio to deploy applications to Azure. But now, I am studying for Microsoft Exam AZ-204 which requires knowing containers. I started with a node.js application that I cloned. In this blog, I show how to build and image and deploy it to Azure.

First, I installed Docker and the Docker Desktop.

I cloned the repository https://github.com/docker/welcome-to-docker.git to my repos folder. The project already has a Docker file. If you are working with a project that does not have a Docker file, you would have to create one.

I made sure I was logged into Docker. It’s important at this point to navigate to the folder containing the project. For my work, I used Powershell 7. The first thing I did was open Powershell

To set up the development environment run

$ docker compose watch

To build the image, I ran

$ docker build

This didn’t work the first time. In my Docker file, I have “FROM node:18-alpine”. I had to run

$ docker pull alpine

Then the build command worked. My image came up on the Docker desktop as “getting-started”.

To run on Azure, I needed was a container registry. I used the Azure UI to create a container registry. I had to push my image to the container registry. At this point, I needed to go back to the command line. To work with Azure from the command line, I had to download and run “azure-cli-2.65.0.msi”

First I ran

$ Connect-AzAccount

Then I needed to login. My username is linked to a number of subscriptions and I had to use the right one. This required

$ az login --tenant <TenantID>

The tenant id for subscriptions is in the Overview of Microsoft Entra ID

Next I tagged the image in Docker desktop. Here are my images in Docker desktop.

This required running

$ docker tag getting-started [registry name].azurecr.io/getting-started getting-started

Here are my images in Docker Desktop

I logged into my registry:

az acr login –name [registry name]

Finally, I ran


$docker push [registry name].azurecr.io/getting-started

Here is the image in my Azure container registry

To run the image on Azure, I created a new resource from the Marketplace “Web App For Containers”. Entering the information is standard. I needed a new App Service plan for Linux. I of course picked a free plan. For image, enter the image from your container registry. Here is my web app: