django-dynamic-admin-forms 0.1.4

Add simple dynamic interaction to the otherwise static django admin.

django-dynamic-admin-forms

Add simple interactions to the otherwise static django admin.

Installation

• Install the package via pip:

  pip install django-dynamic-admin-forms

  or via pipenv:

  pipenv install django-dynamic-admin-forms

• Add the module to INSTALLED_APPS:

  INSTALLED_APPS = (
      ...,
      'dynamic_admin_forms',
      'django.contrib.admin'
      ...
  )    
  

  Ensure that the dynamic_admin_forms comes before the default django.contrib.admin in the list of installed apps, because otherwise the templates, which are overwritten by dynamic_admin_forms won't be found.

• Ensure that the dynamic_admin_forms templates are found via using APP_DIRS setting:

  TEMPLATES = [
      {
          'BACKEND': 'django.template.backends.django.DjangoTemplates',
          'APP_DIRS': True,
          ...
      },
  ]
  

• Run python manage.py collectstatic to include this apps Javascript code in your settings.STATIC_ROOT directory

Usage

• Add the dynamic_admin_forms.DynamicModelAdminMixin to your admin classes

• In addition to the standard fields declaration, specify a list of dynamic_fields

• For each dynamic field, add a method get_dynamic_{field_name}_field to the admin

  • Input: data: Dict[str, Any] - the cleaned form data
  • Output:
    • queryset: Optional[Queryset] - The values to select from
    • value: Any - The value, the field should have (must be compatible to the field type)
    • hidden: Bool - True, if field should be hidden

• A rather non-sensical example:

  from django.contrib import admin
  
  from .models import MyModel
  from dynamic_admin_forms.admin import DynamicModelAdminMixin
  
  
  @admin.register(MyModel)
  class MyModelAdmin(DynamicModelAdminMixin, admin.ModelAdmin):
    fields = ("name", "city")
    dynamic_fields = ("city",)
  
    def get_dynamic_city_field(self, data):
      # automatically choose first city that matches first letter of name 
      name = data.get("name")
      if not name:
        queryset = City.objects.all()
        value = data.get("city")
      else:
        queryset = City.objects.filter(name__startswith=name[0])
        value = queryset.first()
      hidden = not queryset.exists()
      return queryset, value, hidden
  

How it works

Whenever a dynamic form changes, an event handler makes a request to a special endpoint, which returns new HTML to swap into the existing form. This new HTML is directly generated by django.contrib.admin, so we only have to set the outerHTML of the correct HTML elements to update the form.

Limitations

• does not work in conjunction with inlines
• does not validate that the selected value is really part of the original queryset
  • if anybody can modify your DOM, they could potentially inject invalid values
  • you have to write Model.clean() methods to guard against that
• only tested with Django 3.2

Changelog

• 0.1.0: Initial release
• 0.1.1: README fixes
• 0.1.2: README fixes
• 0.1.3: Change Demo-GIF hosting
• 0.1.4: README fixes