Task.Json triggers validation on invisible only fields - azure-devops

Question

I am trying to create a Azure DevOps Pipelines Custom extension. I have a task.json where fields are visible on certain conditions.
For example:
{
"name": "actions",
"type": "picklist",
"label": "Actions",
"defaultValue": "Select",
"required": true,
"helpMarkDown": "Select an Action from the dropdown as per your requirement.",
"options": {
"New": "Add",
"Delete": "Delete"
}
},
{
"name": "backEndIPAddress",
"type": "string",
"label": "IP Address",
"required": true,
"defaultValue": "",
"helpMarkDown": "",
"visibleRule": "actions = New",
"validation": {
"expression": "isMatch(value,'^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?){0,15}$','IgnoreCase')",
"message": "Invalid IP Address. Please try again!"
}
}
The issue when the IPAddress field is hidden, the validation is still tried and it fails. How to ensure that the fields are validated only if they are visible?

Answer 1

A few options:
Set a default value for the input
Update the regex to include ^$| at the start to allow empty values ('require':true will take care of the requiredness)
Remember that there should be a default isIpV4Address(value: string) function so you don't have to specify the regex.
From the docs it looks like there is an upcoming when clause which will dictate when the set of rules should trigger, I suppose this may be causing the currently unwanted behavior.
See also:
https://github.com/Microsoft/vsts-tasks/blob/1d75fa8f66aa1cf7a9cb62946939f30f087b2969/docs/taskinputvalidation.md