ARM Template Custom Expressions in Parameters not saving


When I add an ARM Deployment step in my process with the template added as “Source Code”, and the template contains allowedValues it seems to not save any custom expressions that I define for the parameters.

For example if my template contains a parameter like this:
“environment”: {
“type”: “string”,
“allowedValues”: [
“metadata”: {
“description”: “The type of environment you’re deploying.”

Then I see the dropdown list in the parameters section. Here I select Custom Expression, and define it as #{Environment}.
After saving the step, then re-opening it, I can see that the dropdown list is back and my custom expression is gone.

Is this a bug, or can we not use allowedValues in our templates?


Hi Dan,

Thanks for reaching out. We have an open bug for this, but it seems it has slipped through the cracks a little:

I’ve taken your report as a prompt to kick it up our priority list. A fix has been done and is currently scheduled to go out in our next release.


Great news. Any idea on a time frame for the next release (days/weeks/months)?

Hi Dan,

It should be in the next few days as long as testing on the release goes smoothly.