Passing Enums to Unicorn views

[nerdoc]

According to the docs, passed types must be simple Python types.
I am struggling passing an IntEnum, which in fact is an int, to a view:

<button 
  type="button" 
  class="..." 
  unicorn:click="set_scope({{ scope.DEVICE }})"
>
set scope to DEVICE
</button>

But I get no way to solve this. can I pass the Enum ("Scope" here) as attribute to the view?

class FooView(UnicornView):
    scope = Scope.USER
  # ...

And ideas? Would it be possible to cast Enums/IntEnums to str or ints in Unicorn? I always get the error:

ValueError: malformed node or string on line 1: <ast.Attribute object at 0x7f83bcbbdae0>

[nerdoc]

Hm... I found a bit of an answer after hours now. You have to keep the variable as Enum in the View, and cast it to an Enum when getting it from the template.

class ScopeSwitcherView(UnicornView):
    active_scope: Scope = Scope.USER

    def set_scope(self, scope: int):
        self.active_scope = Scope(scope)

In the template, use ints/strings, by using {{ <enum_name>.<ATTR>.value }}:

<button
    type="button"
    class="btn {% if active_scope == active_scope.GROUP.value %} active{% endif %}"
    unicorn:click="set_scope({{ active_scope.GROUP.value }})"
>Set to GROUP</i></button>

[adamghill]

I added a note about enums here: https://www.django-unicorn.com/docs/actions/#argument-types. Let me know if it could be clarified. I also added an example here: https://github.com/adamghill/django-unicorn/blob/main/example/unicorn/templates/unicorn/objects.html#L108-L117.

[nerdoc]

Very clear. Maybe I would add a comment, and move this one at the last position.

first

I would use set_color({{ color.BLUE.value }})" as first one. It's the clearest...

second

I would add a comment and use that as second (= last one)

<!-- the following is not recommended, as it contradicts the purpose of Enums (but it works): -->
  <button unicorn:click="set_color(2)">Sets `self.color` to `Color.GREEN`</button> 

third...

set_color({{ color.value }})" - eh - does this do anything? because color.value is already color.value... This would never change anything... Couldn't you delete that example altogether?

[adamghill]

because color.value is already color.value... This would never change anything

Yup! I think what I was trying to make clear was an enum could be used directly (if that makes sense). Does this clarify what I was getting at? It still might not be all that helpful. 😆

# enum.py
from django_unicorn.components import UnicornView
from enum import Enum

class Color(Enum):
  RED = 1
  GREEN = 2
  BLUE = 3
  PURPLE = 4

class EnumView(UnicornView):
    color = Color.RED
    purple_color = Color.PURPLE

    def set_color(self, color_int: int):
      self.color = Color(color_int)

<!-- enum.html -->
<div>
  <button unicorn:click="set_color({{ color.BLUE.value }})">Will output BLUE below</button>
  <button unicorn:click="set_color(2)">Will output GREEN below</button>
  <button unicorn:click="set_color({{ purple_color.value }})">Will output PURPLE below</button>

  <br />
  Color: {{ color }}
</div>

[nerdoc]

MUCH better!

[adamghill]

Commit is dd726d9; should go live to the site in a little bit.

Thanks for your help!