Showing posts with label Docker Hub. Show all posts
Showing posts with label Docker Hub. Show all posts

Tuesday, February 2, 2021

Deploying Docker images to Azure App Services

Deploying Docker images to Azure App Services is simple. Learn how to deploy your Docker images to Azure App Services using Azure Container Registry (ACR)
Photo by Glenn Carstens-Peters on Unsplash

We've been discussing Docker, containers and microservices for some time on the blog. On previous posts we learned how to create our own ASP.NET Docker images and how to push them to Azure Container Registry. Today we'll learn how to deploy these same Docker images on Azure App Services.

On this post we will:


As requirements, please make sure you have:
If you want to follow along, please check the previous tutorials discussing how to:

    About Azure App Services

    Azure developers are quite familiar with Azure App Services. But for those who don't know, App services are:
    HTTP-based services for hosting web applications, REST APIs, and mobile back ends. You can develop in your favorite language, be it .NET, .NET Core, Java, Ruby, Node.js, PHP, or Python. Applications run and scale with ease on both Windows and Linux-based environments.

    Why use App Services

    And why use Azure App Services? Essentially because App Services:
    • support multiple languages and frameworks: such as ASP.NET, Java, Ruby, Python and Node.js
    • can be easily plugged into your CI/CD pipelines, for example to deploy from Docker Hub or Azure Container Registries
    • can be used as serverless services
    • runs webjobs allowing us to deploy backend services without any additional costs
    • have a very powerful and intuitive admin interface 
    • are integrated with other Azure services

    Creating our App Service

    So let's get started and create our App Service. While this shouldn't be new to anyone, I'd like to review the workflow so readers understand the step-by-step. To create your App Service, in Azure, click Create -> App Service:
    On this screen, make sure you select:
    • Publish: Docker Container
    • OS: Linux

    Select the free plan

    Click on Change Plan to choose the free one (by default you're set on a paid one). Click Dev/Test and select F1:

    Selecting Docker Container/Linux

    Review the info and don't forget to select Docker Container/Linux for Publish and Operating System:

    Specifying Container Information

    Next, we specify the container information. On this step we will choose:
    • Options: Single Container
    • Image Source: Azure Container Registry
    • Registry: Choose yours
    Change Image Source to Azure Container Registry:
    On this step, Azure should auto-populate your repository. However, if you do not have admin user enabled (I didn't), you'll get this error:

    Enabling Admin in your Azure Container Registry

    To enable admin access to your registry, open it using the portal and on the Identity tab, change from Disable:
    To Enable and Azure will auto-generate the credentials for you:

    Specify your Container

    Back to the creation screen, as soon as the admin access is enabled on your registry, Azure should auto-populate the required information with your registry, image and tag (if one exists):
    Startup Command allows you to specify additional commands for the image (for example environment vars, volumes, configurations, etc).

    Review and Confirm

    Review and confirm. The deployment should take less than 1 second:

    Accessing our App Service in Azure

    As seen above, as soon as confirm, the deployment starts. It shouldn't take more than 1 minute to have it complete.

    Accessing our Web Application

    Let's check if our image is running. From the above image you can see my image's URL highlighted in yellow. Open that on a browser to confirm the site is accessible:

    Container Features

    To finish, let's summarize some features that Azure offers us to easily manage our containers. 

    Container Settings

    Azure still offers a Container Settings tab that allows us to inspect, change container settings for our web app.

    Container Logs

    We can inspect logs for our containers to easily troubleshoot them.
    As an example, here's an excerpt of what I got for my own container log:
    2020-04-10 04:32:51.913 INFO  -  Status: Downloaded newer image for
    2020-04-10 04:32:52.548 INFO  - Pull Image successful, Time taken: 0 Minutes and 47 Seconds
    2020-04-10 04:32:52.627 INFO  - Starting container for site
    2020-04-10 04:32:52.627 INFO  - docker run -d -p 5021:80 --name hildenco-docker_0_e1384f56 -e WEBSITES_ENABLE_APP_SERVICE_STORAGE=false -e WEBSITE_SITE_NAME=hildenco-docker -e WEBSITE_AUTH_ENABLED=False -e PORT=80 -e WEBSITE_ROLE_INSTANCE_ID=0 -e -e WEBSITE_INSTANCE_ID=[redacted] 
    2020-04-10 04:32:52.627 INFO  - Logging is not enabled for this container.
    Please use to enable logging to see container logs here.
    2020-04-10 04:32:57.601 INFO  - Initiating warmup request to container hildenco-docker_0_e1384f56 for site hildenco-docker
    2020-04-10 04:33:02.177 INFO  - Container hildenco-docker_0_e1384f56 for site hildenco-docker initialized successfully and is ready to serve requests.

    Continuous Deployment (CD)

    Another excellent feature that you should explore in the future is enabling continuous deployment on your web apps. Enabling continuous deployment is essential to help your team gain agility by releasing faster and often. We'll try to cover this fantastic topic in the future, keep tuned.


    On this post we reviewed how to create an Azure App Service and learned how to deploy our own Docker Images from our very own Azure Container Registry (ACR) to it. By using ACR greatly simplified the integration between our own Docker Images and our App Services. From here I'd urge you to explore continuous integration to automatically push your images to your App Services as code lands in your git repository.


    See Also

    Thursday, October 1, 2020

    Building and Hosting Docker images on GitHub with GitHub Actions

    Building Docker images for our ASP.NET Core websites is easy and fun. Let's see how.
    Photo by Steve Johnson on Unsplash

    On a previous post we discussed how to build our own Docker images from ASP.NET Core websites, push and host them on GitHub Packages. We also saw how to build and host our own NuGet packages in GitHub. Those approaches are certainly the recommended if you already have a CI/CD implemented for your project. However, for new projects running on GitHub, GitHub Actions deserves your attention.

    What we will build

    On this post we'll review how to build Docker images from a simple ASP.NET Core website and setup continuous integrations using GitHub Actions to automatically build, test and deploy them as GitHub Packages.


    To run this project on your machine, please make sure you have installed:

    If you want to develop/extend/modify it, then I'd suggest you to also have:

    About GitHub Packages

    GitHub Packages is GitHub's offering for those wanting to host their own packages or Docker images. The benefits of using GitHub Packages is that it's free, you can share your images privately or publicly and you can integrate with other GitHub tooling such as APIs, Actions, webhooks and even create complex end-to-end DevOps workflows.

    About GitHub Actions

    GitHub Actions allows automating all your workflows such as build, test, and deployments right from GitHub. We can also use Actions to make code reviews, branch management, and issue triaging. GitHub Actions is very powerful, easy to customize, extend and it counts with lots of pre-configured templates to build and deploy pretty much everything.

    Building our Docker Image

    So let's quickly build our Docker image. For this demo, I'll use my own aspnet-github-actions. If you want to follow along, open a terminal and clone the project with:
    git clone

    Building our local image

    Next, cd into that folder and build a local Docker image with:
    docker build . -t aspnet-gitub-actions
    Now confirm your image was successfully built with:
    docker images

    Testing our image

    With the image built, let's quickly test it by running:
    docker run --rm -d -p 8080:80 --name webapp aspnet-gitthub-actions
    Browse to http://localhost:8080 to confirm it's running:

    Stop the container with the command below as we'll take a look at the setup on GitHub:
    docker stop webapp
    For more information on how to setup and run the application, check the project's README file.

    Setting up Actions

    With the container building and running locally, it's time to setup GitHub Actions. Open your repo and click on Actions:
    From here, you can either add a blank workflow or use a build template for your project. For our simple project I can use the template Publish Docker Container:
    By clicking Set up this workflow, GitHub will add a clone of that file to our repo at ~/.github/workflows/ and will load an editor so we can edit our recently created file. Go ahead and modify it to your needs. Since our Dockerfile is pretty standard, you'll only need to change the IMAGE_NAME to something adequate to your image:

    Running the Workflow

    As soon as you add that file, GitHub will run your first action. If you haven't pushed your code yet it'll probably fail:
    To fix the error above, go ahead and push some code (or reuse mine if you wish). Assuming you have a working Dockerfile in the root of your project (where the script expects it to be), you should see your next project being queued and run. The UI is pretty cool and allows you to inspect the process in real time:
    If the workflow finishes successfully, we'll get a confirmation like:
    Failed again? Did you update IMAGE_NAME as explained on the previous step?

    Accessing the Packages

    To view your Docker images, go to the project's page and click on Packages link:
    By clicking on your package, you'll see other details about your package, including how to pull it and run it locally:

    Running our Packages

    From there, the only thing remaining would be running our recently created packages. Since we already discussed in detail how to host and use our Docker images from GitHub packages, fell free to jump that post to learn how.

    Final Thoughts

    On this post we reviewed how to automatically build Docker images using GitHub Actions. GitHub Actions makes it easy to automate all your workflows including CI/CD, builds, test, and deployments. Hosting our Docker images on GitHub is valuable as you can share your images privately or with the rest of the world, integrate with GitHub tools and even create complex DevOps workflows. Other common scenarios would be building our images on GitHub and pushing them to Docker Hub or even auto-deploying them to the cloud. We'll evaluate those in the future so keep tuned!

    Source Code

    As always, the source code is available on GitHub.

    See Also

    About the Author

    Bruno Hildenbrand      
    Principal Architect, HildenCo Solutions.