django-constance/constance/admin.py

from collections import OrderedDict
from datetime import date
from datetime import datetime
from operator import itemgetter

from django import forms
from django import get_version
from django.apps import apps
from django.contrib import admin
from django.contrib import messages
from django.contrib.admin.options import csrf_protect_m
from django.core.exceptions import PermissionDenied
from django.http import HttpResponseRedirect
from django.template.response import TemplateResponse
from django.urls import path
from django.utils.formats import localize
from django.utils.translation import gettext_lazy as _

from . import LazyConfig
from . import settings
from .forms import ConstanceForm
from .utils import get_values

config = LazyConfig()


class ConstanceAdmin(admin.ModelAdmin):
    change_list_template = 'admin/constance/change_list.html'
    change_list_form = ConstanceForm

    def __init__(self, model, admin_site):
        model._meta.concrete_model = Config
        super().__init__(model, admin_site)

    def get_urls(self):
        info = f'{self.model._meta.app_label}_{self.model._meta.module_name}'
        return [
            path('', self.admin_site.admin_view(self.changelist_view), name=f'{info}_changelist'),
            path('', self.admin_site.admin_view(self.changelist_view), name=f'{info}_add'),
        ]

    def get_config_value(self, name, options, form, initial):
        default, help_text = options[0], options[1]
        field_type = None
        if len(options) == 3:
            field_type = options[2]
        # First try to load the value from the actual backend
        value = initial.get(name)
        # Then if the returned value is None, get the default
        if value is None:
            value = getattr(config, name)

        form_field = form[name]
        config_value = {
            'name': name,
            'default': localize(default),
            'raw_default': default,
            'help_text': _(help_text),
            'value': localize(value),
            'modified': localize(value) != localize(default),
            'form_field': form_field,
            'is_date': isinstance(default, date),
            'is_datetime': isinstance(default, datetime),
            'is_checkbox': isinstance(form_field.field.widget, forms.CheckboxInput),
            'is_file': isinstance(form_field.field.widget, forms.FileInput),
        }
        if field_type and field_type in settings.ADDITIONAL_FIELDS:
            serialized_default = form[name].field.prepare_value(default)
            config_value['default'] = serialized_default
            config_value['raw_default'] = serialized_default
            config_value['value'] = form[name].field.prepare_value(value)

        return config_value

    def get_changelist_form(self, request):
        """Returns a Form class for use in the changelist_view."""
        # Defaults to self.change_list_form in order to preserve backward
        # compatibility
        return self.change_list_form

    @csrf_protect_m
    def changelist_view(self, request, extra_context=None):
        if not self.has_view_or_change_permission(request):
            raise PermissionDenied
        initial = get_values()
        form_cls = self.get_changelist_form(request)
        form = form_cls(initial=initial, request=request)
        if request.method == 'POST' and request.user.has_perm('constance.change_config'):
            form = form_cls(data=request.POST, files=request.FILES, initial=initial, request=request)
            if form.is_valid():
                form.save()
                messages.add_message(request, messages.SUCCESS, _('Live settings updated successfully.'))
                return HttpResponseRedirect('.')
            messages.add_message(request, messages.ERROR, _('Failed to update live settings.'))
        context = dict(
            self.admin_site.each_context(request),
            config_values=[],
            title=self.model._meta.app_config.verbose_name,
            app_label='constance',
            opts=self.model._meta,
            form=form,
            media=self.media + form.media,
            icon_type='svg',
            django_version=get_version(),
        )
        for name, options in settings.CONFIG.items():
            context['config_values'].append(self.get_config_value(name, options, form, initial))

        if settings.CONFIG_FIELDSETS:
            if isinstance(settings.CONFIG_FIELDSETS, dict):
                fieldset_items = settings.CONFIG_FIELDSETS.items()
            else:
                fieldset_items = settings.CONFIG_FIELDSETS

            context['fieldsets'] = []
            for fieldset_title, fieldset_data in fieldset_items:
                if isinstance(fieldset_data, dict):
                    fields_list = fieldset_data['fields']
                    collapse = fieldset_data.get('collapse', False)
                else:
                    fields_list = fieldset_data
                    collapse = False

                absent_fields = [field for field in fields_list if field not in settings.CONFIG]
                if any(absent_fields):
                    raise ValueError(
                        'CONSTANCE_CONFIG_FIELDSETS contains field(s) that does not exist(s): {}'.format(
                            ', '.join(absent_fields)
                        )
                    )

                config_values = []

                for name in fields_list:
                    options = settings.CONFIG.get(name)
                    if options:
                        config_values.append(self.get_config_value(name, options, form, initial))
                fieldset_context = {'title': fieldset_title, 'config_values': config_values}

                if collapse:
                    fieldset_context['collapse'] = True
                context['fieldsets'].append(fieldset_context)
            if not isinstance(settings.CONFIG_FIELDSETS, (OrderedDict, tuple)):
                context['fieldsets'].sort(key=itemgetter('title'))

        if not isinstance(settings.CONFIG, OrderedDict):
            context['config_values'].sort(key=itemgetter('name'))
        request.current_app = self.admin_site.name
        return TemplateResponse(request, self.change_list_template, context)

    def has_add_permission(self, *args, **kwargs):
        return False

    def has_delete_permission(self, *args, **kwargs):
        return False

    def has_change_permission(self, request, obj=None):
        if settings.SUPERUSER_ONLY:
            return request.user.is_superuser
        return super().has_change_permission(request, obj)


class Config:
    class Meta:
        app_label = 'constance'
        object_name = 'Config'
        concrete_model = None
        model_name = module_name = 'config'
        verbose_name_plural = _('config')
        abstract = False
        swapped = False

        def get_ordered_objects(self):
            return False

        def get_change_permission(self):
            return f'change_{self.model_name}'

        @property
        def app_config(self):
            return apps.get_app_config(self.app_label)

        @property
        def label(self):
            return f'{self.app_label}.{self.object_name}'

        @property
        def label_lower(self):
            return f'{self.app_label}.{self.model_name}'

    _meta = Meta()


admin.site.register([Config], ConstanceAdmin)