Delay task in Azure Pipeline cannot be cancelled - azure-devops

Question

I have a recurring issue with an Azure Pipeline YAML template that cannot be cancelled once started. The template defines a release stage that includes 3 jobs:
stage: Release
jobs:
- job: Wait
steps:
- task: Delay#1
inputs:
delayForMinutes: ${{ parameters.ReleaseDelay }}
- deployment: Deploy
dependsOn:
- Wait
# several more tasks that work fine
- job: Cleanup # works fine also
Our workflow is such that sometimes, we want to go ahead and approve a deployment, but we would like to queue it to wait for a couple hours, e.g. to prep updates to release after business hours. It works fine normally.
The issue comes if we try to cancel the Wait task through the pipeline Web UI. Once the release environment approval has been granted and the wait task has started, the pipeline execution cannot be cancelled.
I've tested this with multiple pipelines that reuse this template and it is a persistent/reproducible issue.
So, my question is, is the Microsoft built-in Delay task inherently un-interruptable, or is my dependency in the successor task somehow locking the Delay from being able to be cancelled?
The pipeline will show a status of "Cancelled" once I click the confirmation button to cancel the run, but the task continues to execute as if I had not done so. Crucially, it also does not cancel at the end of the Wait task. It will start straight into the deployment job as if it never received the order to cancel.
The Azure Pipelines docs do not mention the Delay task being un-interruptable, and I can cancel other tasks at different places in the pipeline which also have dependencies defined, so I don't think it's the fault of the dependency declaration, but that's also a secondary candidate for investigation.

Answer 1

You could investigate using the manual validation task instead of the delay task
Using this you could set a timeout but have the ability to shortcut the timeout by resuming the pipeline. Set the task to "resume" once the timeout has been reached.
Your YAML would look something like this
stage: Release
jobs:
- job: waitForValidation
displayName: Wait for external validation
pool: server
steps:
- task: ManualValidation#0
timeoutInMinutes: ${{ parameters.ReleaseDelay }}
inputs:
notifyUsers: |
test#test.com
example#example.com
instructions: 'Please validate the build configuration and resume'
onTimeout: 'resume'
- deployment: Deploy
dependsOn:
- waitForValidation
# several more tasks that work fine
- job: Cleanup # works fine also
Note that this type of task can only be run on on an "Agentless" job so don't forget to set the pool on that job to "server" e.g. pool: server