When I launch a heat template with constraints custom_constraint and allowed_values on one parameter it fails

[Martin Paulo]

We have just upgraded from Juno to Liberty.

A heat template (that used to work in Juno) declares the following parameter:
  instance_type:
    type: string
    description: The flavour the webserver is to run on
    default: m2.xsmall
    constraints:
      - allowed_values: [m2.xsmall, m2.small, m1.small]
        description:
          Must be a valid flavour, limited to the smaller ones available
      - custom_constraint: nova.flavor

When I try to load it via the dashboard, the drop down for the parameter no longer shows the allowed values, instead now listing all of the possible values. And when I select a value and launch the stack, I get the error message:
Error: ERROR: Parameter 'instance_type' is invalid: Must be a valid NeCTAR flavour, limited to the smaller ones available
And the stack fails to launch.

However, it launches quite happily from the command line.

If I comment either of the constraints out, the template works in the dashboard.

If I comment out the allowed_values constraint, I get a list of the flavors that I can select. So I'm guessing that you have written some helpful code to list the available flavors if I constrain it to nova.flavors: and that this is clashing with the allowed_values somehow...

[Lin Hua Cheng (lin-hua-cheng)]

Looking at the code, it seems that the two option can't be used at the same time: https://github.com/openstack/horizon/blob/master/openstack_dashboard/dashboards/project/stacks/forms.py#L327-L336

If custom constraint is used, the allowedvalues is not applied anymore.

The change was introduced here: https://review.openstack.org/#/c/133270/

I suppose the expected behavior is:
1. Apply the custom constraint to get the list of Values
2. then if AllowedValues is defined, filter the list returned.

[Akihiro Motoki (amotoki)]

heat panel is split out to heat-dashboard. Retargeting to heat-dashboard.