We have discussed "Windows AKS Scaled Jobs Handle Graceful Termination for dotnet App using IHostedService When Preemption" previously. However, for Linux scaled jobs we have to handle the graceful termination, using a bash script intead of a PowerShell script.
We can create a script with bash as shown below.
We have discussed "Gracefully Shut Down dotnet 8 IHostedService App - Deployed as a Windows Container in AKS - While Scale In or Pod Deallocations" previously. The approach works fine for pods deployed as a deployment in kubernetes. Similary to the deployment pods, scaled job pod can be terminated abruptly due to preemption in kubernetes, if a high priority pod is scheduled. One way to reolve abrupt termination of scaled job pod due to preemption, would be to assign all scaled jobs to highest possible priority. However, setting highest prority to all scaled jobs is not a good solution, as the job may not require highest priority and job should be able to scheduled after other high priority app pods. Let's look at a better solution that can be implented with pre stop hook for scaled jobs running with base docker image Windows server core 2022.
We can use matrix in GitHub Actions to use a single defnition of job to create multiple jobs as described here in the documentation. Let's say we input the list of application names we want to build, as an input parameter to the action workflow, and need to have the ability to remove the items from the app list at the time of triggering it manually (run workflow). For example, we have 4 apps by default. However, when we need we should be able to build only one or two out of them using the same action workflow without having to change, the workflow defintion. In this post let's explore how we can achieve that with GitHub actions workflow, utilizing the matrix strategy, and dynamical setting the matrix value.
In previous posts we discussed "Setting Up Kubernetes Event Drivern Autoscaling (KEDA) in AKS with Workload Identity" and how to "Set Up (KEDA) Authentication Trigger for Azure Storage Queue/Service Bus in AKS". With that now we can proceed to setup kubernetes scaled job in AKS to run a pod when the Azure service bus queue received a message. Using scaled job we are going to start a job (pod) once a messsage is received in the queue and then receive the massage in the pod container app, process and complete the message and complete the job execution with a pod complete. So, there will be a different pod and a container (kubernetes job) processing each message recived in the Azure service bus queue.
