Windows Docker Sample

Sample Windows apps running in Docker containers consisting of:

• ASP.NET Framework Web API to persist JSON files to a host volume
• .NET Framework Windows Service to watch a host volume for new files
• Includes Docker Compose and Kubernetes manifests

graph LR
A(REST Client) -- POST --> B[ASP.NET Web API]
B-- Save --> C(Host Volume or Bind mount)
D[Windows Service] -- File Watcher --> C

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Apps built with .NET Framework 4.8.1 on Visual Studio 2022.

To run Dockerized versions locally, you'll need a Docker environment like Docker Desktop and internet access to mcr.microsoft.com to pull the base container images (these are quite large, several GB in size).

MyNewService - Windows Service (.NET Framework)

To test locally without installing as a service:

• Create the directory C:\uploads\
• Change project Output Type to "Console Application"
• Press F5 to build and run/debug
• Output logs appear in the console
• Copy a JSON file to C:\uploads\
• PRess ENTER to exit

To test as a Windows Service:

• installutil MyNewService.exe
• Open the Services desktop app. Press Windows+R to open the Run box, enter services.msc, and then press Enter or select OK.
• To start the service, choose Start from the service's shortcut menu.
• Output logs appear in the Event Log (open the Event Viewer to see these)
• To stop the service, choose Stop from the service's shortcut menu.
• To uninstall the service: installutil.exe /u MyNewService.exe

WebUploaderApp - ASP.NET Framework Web API

To test locally:

• Create the directory C:\uploads\
• Make a HTTP POST request to the API:

curl -i -X POST -H "Content-type: application/json" https://localhost:44334/api/Docs -d @payload1.json

• Check C:\uploads\ for the file

Run everything with Visual Studio 2022

• Ensure multiple start-up projects are selected in the solution properties: Project(s): WebUploaderApp and MyNewService, Action: Start
• Press F5 to build and run/debug

Dockerize the Windows Service

docker build -t mynewservice:v1.0 .
docker run --rm --name mynewservice mynewservice:v1.0
docker exec -ti mynewservice -- powershell
Get-Service-Name "MyNewService"
cd c:\uploads\
echo "test"> test1.json
exit

Dockerize the ASP.NET Web API

docker build -t webuploaderapp:v1.0 .
docker run --rm --name webuploaderapp -p 8080:80 webuploaderapp:v1.0
curl -i -X POST -H "Content-type: application/json" http://localhost:8080/api/Docs -d @payload1.json

Run everything with Docker Compose

mkdir ./uploads
docker-compose up
curl -i -X POST -H "Content-type: application/json" http://localhost:8080/api/Docs -d @payload1.json
dir ./uploads
# payload1.json# CTRL+C to stop

Deploy to Azure Kubernetes Service

Create a basic AKS cluster (not for production, just for demo purposes)

$Cluster_Name="winappaks"$Resource_Group="winappdemo"# Adjust to a region near you$Location="australiaeast"

Create the AKS cluster:

az group create --name $Resource_Group--location $Location$Kubernetes_Latest_Version=(az aks get-versions--location $Location--query "values[?!isPreview].version"--output tsv) -split'\n'|Sort-Object {[Version]$_} -Descending |Select-Object-First 1if (Test-Path"win-password.txt") {
$Win_Password=Get-Content"win-password.txt"
} else {
$Win_Password= [System.Convert]::ToBase64String((1..32|%{Get-Random-Maximum 256}))
$Win_Password|Out-File"win-password.txt"
}
$Win_User="azureuser"
az aks create `--resource-group $Resource_Group`--name $Cluster_Name`--node-count 2`--enable-addons monitoring `--generate-ssh-keys `--network-plugin azure `--enable-managed-identity `--windows-admin-username $Win_User`--windows-admin-password $Win_Password`--kubernetes-version $Kubernetes_Latest_Version
az aks get-credentials--resource-group $Resource_Group--name $Cluster_Name
az aks install-cli

Add a Windows node pool to the cluster:

# Add a 4 vCore node pool running Windows Server 2022
az aks nodepool add `--resource-group $Resource_Group`--cluster-name $Cluster_Name`--os-type Windows `--name npwin `--node-count 1`--node-vm-size Standard_D4s_v3 `--kubernetes-version $Kubernetes_Latest_Version

Query the cluster nodes:

kubectl get nodes -o wide

Create Azure Container Registry (ACR) for storing container images:

# append random digits to make unique$ACR_Name="winappacr$((Get-Random-Minimum 1000-Maximum 9999).ToString())" az acr create --resource-group $Resource_Group--name $ACR_Name--sku Standard --location $Location

Grant image pull access to ACR from the AKS cluster:

az aks update -n $Cluster_Name-g $Resource_Group--attach-acr $ACR_Name

Build and push the container images to ACR using ACR build tasks for Windows container images:

az acr build --registry $ACR_Name--image mynewservice:v1.0--file .\MyNewService\Dockerfile .\MyNewService\ --platform windows
az acr build --registry $ACR_Name--image webuploaderapp:v1.0--file .\WebUploaderApp\Dockerfile .\WebUploaderApp\ --platform windows

Create a namespace for the Windows apps:

kubectl create namespace winapp

Create a custom storage class for Azure Files premium storage:

kubectl apply -f kubernetes/docs-afs.sc.yaml

Create the Azure Files PVC:

kubectl apply -f kubernetes\docs-pvc.yaml --namespace winapp

Deploy the Windows Service to the cluster:

# Update the image reference to point to your ACR name
kubectl apply -f kubernetes\mynewservice.app.yaml --namespace winapp
$MyNewService_Pod_Name=(kubectl get pods -n winapp -l app=mynewservice -o jsonpath='{.items[0].metadata.name}')
kubectl logs $MyNewService_Pod_Name-n winapp -f

Deploy the ASP.NET Web API to the cluster:

# Update the image reference to point to your ACR name
kubectl apply -f kubernetes\webuploader.app.yaml --namespace winapp
$WebUploader_Pod_Name=(kubectl get pods -n winapp -l app=webuploader -o jsonpath='{.items[0].metadata.name}')
kubectl logs $WebUploader_Pod_Name-n winapp -f
kubectl port-forward svc/webuploader 8080:80-n winapp
curl -i -X POST -H "Content-type: application/json" http://localhost:8080/api/Docs -d @payload1.json
curl -i -X POST -H "Content-type: application/json" http://localhost:8080/api/Docs -d @payload2.json

Check the logs for MyNewService.

You can also browse the files in the Azure Files storage account in The Azure Portal - look for the Managed Resource group for AKS, unless you used static provisioning of the Azure Files storage account.

(Optional) Setup Ingress Controller

$Namespace=ingress-basic
helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx
helm repo update
helm install ingress-nginx ingress-nginx/ingress-nginx `--create-namespace `--namespace $Namespace`--set controller.service.annotations."service\.beta\.kubernetes\.io/azure-load-balancer-health-probe-request-path"=/healthz
$Ingress_IP=(kubectl get services -n $Namespace ingress-nginx-controller -o jsonpath='{.status.loadBalancer.ingress[0].ip}')
# Name to associate with public IP address$DNS_Label="webuploader$((Get-Random-Minimum 1000-Maximum 9999).ToString())"
echo $DNS_Label# Get the resource-id of the public IP$Public_IP_Res_Id=$(az network public-ip list --query "[?ipAddress!=null]|[?contains(ipAddress, '$Ingress_IP')].[id]"--output tsv)
# Update public IP address with DNS name
az network public-ip update --ids $Public_IP_Res_Id--dns-name $DNS_Label# Display the FQDN
az network public-ip show --ids $Public_IP_Res_Id--query "[dnsSettings.fqdn]"--output tsv
# e.g. webuploaderXXXXXX.australiaeast.cloudapp.azure.com
kubectl apply -f .\kubernetes\webuploader.ingress.yaml -n winapp

Access the Web API using: https://webuploaderXXXXXX.australiaeast.cloudapp.azure.com/api/Docs

(Optional) Configure TLS on Ingress Controller with Let's Encrypt

# TODO: refer to https://learn.microsoft.com/en-us/azure/aks/ingress-tls

Monitoring and Logs

• In the Azure Portal, open the AKS resource blade
• On the left nav menu, select Monitoring / Logs and try these container log queries:

ContainerLog
| where LogEntry contains"MyNewService - "
| where LogEntry contains"Message"

ContainerLog
| where LogEntry contains"MyNewService - "
| where LogEntry contains"Message"
| where LogEntry !contains"Monitoring"
| parse LogEntry with * "MyNewService - " updateType ": " filePath
| summarize Count=count() by updateType

• View as a Table.
• View as a Chart.

Resources / Credits

• https://learn.microsoft.com/en-us/dotnet/framework/windows-services/walkthrough-creating-a-windows-service-application-in-the-component-designer
• https://learn.microsoft.com/en-us/dotnet/framework/windows-services/service-application-programming-architecture
• https://learn.microsoft.com/en-us/dotnet/api/system.io.filesystemwatcher?view=netframework-4.8.1
• https://github.com/mihaitibrea/docker-windows-service/tree/master - Example to run a Windows Service in a Docker container
• https://learn.microsoft.com/en-us/azure/aks/ingress-tls - AKS Ingress with TLS