| title | description | services | ms.topic | ms.date | ms.custom |
|---|---|---|---|---|---|
Kubernetes on Azure tutorial - Prepare an application |
In this Azure Kubernetes Service (AKS) tutorial, you learn how to prepare and build a multi-container app with Docker Compose that you can then deploy to AKS. |
container-service |
tutorial |
01/12/2021 |
mvc |
In this tutorial, part one of seven, a multi-container application is prepared for use in Kubernetes. Existing development tools such as Docker Compose are used to locally build and test an application. You learn how to:
[!div class="checklist"]
- Clone a sample application source from GitHub
- Create a container image from the sample application source
- Test the multi-container application in a local Docker environment
Once completed, the following application runs in your local development environment:
:::image type="content" source="./media/container-service-kubernetes-tutorials/azure-vote-local.png" alt-text="Screenshot showing the container image Azure Voting App running locally opened in a local web browser" lightbox="./media/container-service-kubernetes-tutorials/azure-vote-local.png":::
In later tutorials, the container image is uploaded to an Azure Container Registry, and then deployed into an AKS cluster.
This tutorial assumes a basic understanding of core Docker concepts such as containers, container images, and docker commands. For a primer on container basics, see Get started with Docker.
To complete this tutorial, you need a local Docker development environment running Linux containers. Docker provides packages that configure Docker on a Mac, Windows, or Linux system.
Note
Azure Cloud Shell does not include the Docker components required to complete every step in these tutorials. Therefore, we recommend using a full Docker development environment.
The sample application used in this tutorial is a basic voting app consisting of a front-end web component and a back-end Redis instance. The web component is packaged into a custom container image. The Redis instance uses an unmodified image from Docker Hub.
Use git to clone the sample application to your development environment:
git clone https://github.com/Azure-Samples/azure-voting-app-redis.gitChange into the cloned directory.
cd azure-voting-app-redisInside the directory is the application source code, a pre-created Docker compose file, and a Kubernetes manifest file. These files are used throughout the tutorial set. The contents and structure of the directory are as follows:
azure-voting-app-redis
│ azure-vote-all-in-one-redis.yaml
│ docker-compose.yaml
│ LICENSE
│ README.md
│
├───azure-vote
│ │ app_init.supervisord.conf
│ │ Dockerfile
│ │ Dockerfile-for-app-service
│ │ sshd_config
│ │
│ └───azure-vote
│ │ config_file.cfg
│ │ main.py
│ │
│ ├───static
│ │ default.css
│ │
│ └───templates
│ index.html
│
└───jenkins-tutorial
config-jenkins.sh
deploy-jenkins-vm.sh
Docker Compose can be used to automate building container images and the deployment of multi-container applications.
Use the sample docker-compose.yaml file to create the container image, download the Redis image, and start the application:
docker-compose up -dWhen completed, use the docker images command to see the created images. Three images have been downloaded or created. The azure-vote-front image contains the front-end application and uses the nginx-flask image as a base. The redis image is used to start a Redis instance.
$ docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
mcr.microsoft.com/azuredocs/azure-vote-front v1 84b41c268ad9 9 seconds ago 944MB
mcr.microsoft.com/oss/bitnami/redis 6.0.8 3a54a920bb6c 2 days ago 103MB
tiangolo/uwsgi-nginx-flask python3.6 a16ce562e863 6 weeks ago 944MB
Run the docker ps command to see the running containers:
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
d10e5244f237 mcr.microsoft.com/azuredocs/azure-vote-front:v1 "/entrypoint.sh /sta…" 3 minutes ago Up 3 minutes 443/tcp, 0.0.0.0:8080->80/tcp azure-vote-front
21574cb38c1f mcr.microsoft.com/oss/bitnami/redis:6.0.8 "/opt/bitnami/script…" 3 minutes ago Up 3 minutes 0.0.0.0:6379->6379/tcp azure-vote-back
To see the running application, enter http://localhost:8080 in a local web browser. The sample application loads, as shown in the following example:
:::image type="content" source="./media/container-service-kubernetes-tutorials/azure-vote-local.png" alt-text="Screenshot showing the container image Azure Voting App running locally opened in a local web browser" lightbox="./media/container-service-kubernetes-tutorials/azure-vote-local.png":::
Now that the application's functionality has been validated, the running containers can be stopped and removed. Do not delete the container images - in the next tutorial, the azure-vote-front image is uploaded to an Azure Container Registry instance.
Stop and remove the container instances and resources with the docker-compose down command:
docker-compose downWhen the local application has been removed, you have a Docker image that contains the Azure Vote application, azure-vote-front, for use with the next tutorial.
In this tutorial, an application was tested and container images created for the application. You learned how to:
[!div class="checklist"]
- Clone a sample application source from GitHub
- Create a container image from the sample application source
- Test the multi-container application in a local Docker environment
Advance to the next tutorial to learn how to store container images in Azure Container Registry.
[!div class="nextstepaction"] Push images to Azure Container Registry