root/django/trunk/django/contrib/admin/options.py

from django import forms, template
from django.forms.formsets import all_valid
from django.forms.models import modelform_factory, inlineformset_factory
from django.forms.models import BaseInlineFormSet
from django.contrib.contenttypes.models import ContentType
from django.contrib.admin import widgets
from django.contrib.admin import helpers
from django.contrib.admin.util import quote, unquote, flatten_fieldsets, get_deleted_objects
from django.core.exceptions import PermissionDenied
from django.db import models, transaction
from django.http import Http404, HttpResponse, HttpResponseRedirect
from django.shortcuts import get_object_or_404, render_to_response
from django.utils.html import escape
from django.utils.safestring import mark_safe
from django.utils.text import capfirst, get_text_list
from django.utils.translation import ugettext as _
from django.utils.encoding import force_unicode
try:
    set
except NameError:
    from sets import Set as set     # Python 2.3 fallback

HORIZONTAL, VERTICAL = 1, 2
# returns the <ul> class for a given radio_admin field
get_ul_class = lambda x: 'radiolist%s' % ((x == HORIZONTAL) and ' inline' or '')

class IncorrectLookupParameters(Exception):
    pass

class BaseModelAdmin(object):
    """Functionality common to both ModelAdmin and InlineAdmin."""
    raw_id_fields = ()
    fields = None
    exclude = None
    fieldsets = None
    form = forms.ModelForm
    filter_vertical = ()
    filter_horizontal = ()
    radio_fields = {}
    prepopulated_fields = {}

    def formfield_for_dbfield(self, db_field, **kwargs):
        """
        Hook for specifying the form Field instance for a given database Field
        instance.

        If kwargs are given, they're passed to the form Field's constructor.
        """
        
        # If the field specifies choices, we don't need to look for special
        # admin widgets - we just need to use a select widget of some kind.
        if db_field.choices:
            if db_field.name in self.radio_fields:
                # If the field is named as a radio_field, use a RadioSelect
                kwargs['widget'] = widgets.AdminRadioSelect(attrs={
                    'class': get_ul_class(self.radio_fields[db_field.name]),
                })
                kwargs['choices'] = db_field.get_choices(
                    include_blank = db_field.blank,
                    blank_choice=[('', _('None'))]
                )
                return db_field.formfield(**kwargs)
            else:
                # Otherwise, use the default select widget.
                return db_field.formfield(**kwargs)

        # For DateTimeFields, use a special field and widget.
        if isinstance(db_field, models.DateTimeField):
            kwargs['form_class'] = forms.SplitDateTimeField
            kwargs['widget'] = widgets.AdminSplitDateTime()
            return db_field.formfield(**kwargs)

        # For DateFields, add a custom CSS class.
        if isinstance(db_field, models.DateField):
            kwargs['widget'] = widgets.AdminDateWidget
            return db_field.formfield(**kwargs)

        # For TimeFields, add a custom CSS class.
        if isinstance(db_field, models.TimeField):
            kwargs['widget'] = widgets.AdminTimeWidget
            return db_field.formfield(**kwargs)
        
        # For TextFields, add a custom CSS class.
        if isinstance(db_field, models.TextField):
            kwargs['widget'] = widgets.AdminTextareaWidget
            return db_field.formfield(**kwargs)
        
        # For URLFields, add a custom CSS class.
        if isinstance(db_field, models.URLField):
            kwargs['widget'] = widgets.AdminURLFieldWidget
            return db_field.formfield(**kwargs)
        
        # For IntegerFields, add a custom CSS class.
        if isinstance(db_field, models.IntegerField):
            kwargs['widget'] = widgets.AdminIntegerFieldWidget
            return db_field.formfield(**kwargs)

        # For CommaSeparatedIntegerFields, add a custom CSS class.
        if isinstance(db_field, models.CommaSeparatedIntegerField):
            kwargs['widget'] = widgets.AdminCommaSeparatedIntegerFieldWidget
            return db_field.formfield(**kwargs)

        # For TextInputs, add a custom CSS class.
        if isinstance(db_field, models.CharField):
            kwargs['widget'] = widgets.AdminTextInputWidget
            return db_field.formfield(**kwargs)
    
        # For FileFields and ImageFields add a link to the current file.
        if isinstance(db_field, models.ImageField) or isinstance(db_field, models.FileField):
            kwargs['widget'] = widgets.AdminFileWidget
            return db_field.formfield(**kwargs)

        # For ForeignKey or ManyToManyFields, use a special widget.
        if isinstance(db_field, (models.ForeignKey, models.ManyToManyField)):
            if isinstance(db_field, models.ForeignKey) and db_field.name in self.raw_id_fields:
                kwargs['widget'] = widgets.ForeignKeyRawIdWidget(db_field.rel)
            elif isinstance(db_field, models.ForeignKey) and db_field.name in self.radio_fields:
                kwargs['widget'] = widgets.AdminRadioSelect(attrs={
                    'class': get_ul_class(self.radio_fields[db_field.name]),
                })
                kwargs['empty_label'] = db_field.blank and _('None') or None
            else:
                if isinstance(db_field, models.ManyToManyField):
                    # If it uses an intermediary model, don't show field in admin.
                    if db_field.rel.through is not None:
                        return None
                    elif db_field.name in self.raw_id_fields:
                        kwargs['widget'] = widgets.ManyToManyRawIdWidget(db_field.rel)
                        kwargs['help_text'] = ''
                    elif db_field.name in (list(self.filter_vertical) + list(self.filter_horizontal)):
                        kwargs['widget'] = widgets.FilteredSelectMultiple(db_field.verbose_name, (db_field.name in self.filter_vertical))
            # Wrap the widget's render() method with a method that adds
            # extra HTML to the end of the rendered output.
            formfield = db_field.formfield(**kwargs)
            # Don't wrap raw_id fields. Their add function is in the popup window.
            if not db_field.name in self.raw_id_fields:
                # formfield can be None if it came from a OneToOneField with
                # parent_link=True
                if formfield is not None:
                    formfield.widget = widgets.RelatedFieldWidgetWrapper(formfield.widget, db_field.rel, self.admin_site)
            return formfield

        # For any other type of field, just call its formfield() method.
        return db_field.formfield(**kwargs)

    def _declared_fieldsets(self):
        if self.fieldsets:
            return self.fieldsets
        elif self.fields:
            return [(None, {'fields': self.fields})]
        return None
    declared_fieldsets = property(_declared_fieldsets)

class ModelAdmin(BaseModelAdmin):
    "Encapsulates all admin options and functionality for a given model."
    __metaclass__ = forms.MediaDefiningClass

    list_display = ('__str__',)
    list_display_links = ()
    list_filter = ()
    list_select_related = False
    list_per_page = 100
    search_fields = ()
    date_hierarchy = None
    save_as = False
    save_on_top = False
    ordering = None
    inlines = []

    # Custom templates (designed to be over-ridden in subclasses)
    change_form_template = None
    change_list_template = None
    delete_confirmation_template = None
    object_history_template = None

    def __init__(self, model, admin_site):
        self.model = model
        self.opts = model._meta
        self.admin_site = admin_site
        self.inline_instances = []
        for inline_class in self.inlines:
            inline_instance = inline_class(self.model, self.admin_site)
            self.inline_instances.append(inline_instance)
        super(ModelAdmin, self).__init__()

    def __call__(self, request, url):
        # Delegate to the appropriate method, based on the URL.
        if url is None:
            return self.changelist_view(request)
        elif url == "add":
            return self.add_view(request)
        elif url.endswith('/history'):
            return self.history_view(request, unquote(url[:-8]))
        elif url.endswith('/delete'):
            return self.delete_view(request, unquote(url[:-7]))
        else:
            return self.change_view(request, unquote(url))

    def _media(self):
        from django.conf import settings

        js = ['js/core.js', 'js/admin/RelatedObjectLookups.js']
        if self.prepopulated_fields:
            js.append('js/urlify.js')
        if self.opts.get_ordered_objects():
            js.extend(['js/getElementsBySelector.js', 'js/dom-drag.js' , 'js/admin/ordering.js'])

        return forms.Media(js=['%s%s' % (settings.ADMIN_MEDIA_PREFIX, url) for url in js])
    media = property(_media)

    def has_add_permission(self, request):
        "Returns True if the given request has permission to add an object."
        opts = self.opts
        return request.user.has_perm(opts.app_label + '.' + opts.get_add_permission())

    def has_change_permission(self, request, obj=None):
        """
        Returns True if the given request has permission to change the given
        Django model instance.

        If `obj` is None, this should return True if the given request has
        permission to change *any* object of the given type.
        """
        opts = self.opts
        return request.user.has_perm(opts.app_label + '.' + opts.get_change_permission())

    def has_delete_permission(self, request, obj=None):
        """
        Returns True if the given request has permission to change the given
        Django model instance.

        If `obj` is None, this should return True if the given request has
        permission to delete *any* object of the given type.
        """
        opts = self.opts
        return request.user.has_perm(opts.app_label + '.' + opts.get_delete_permission())

    def queryset(self, request):
        """
        Returns a QuerySet of all model instances that can be edited by the
        admin site. This is used by changelist_view.
        """
        qs = self.model._default_manager.get_query_set()
        # TODO: this should be handled by some parameter to the ChangeList.
        ordering = self.ordering or () # otherwise we might try to *None, which is bad ;)
        if ordering:
            qs = qs.order_by(*ordering)
        return qs

    def get_fieldsets(self, request, obj=None):
        "Hook for specifying fieldsets for the add form."
        if self.declared_fieldsets:
            return self.declared_fieldsets
        form = self.get_form(request, obj)
        return [(None, {'fields': form.base_fields.keys()})]

    def get_form(self, request, obj=None, **kwargs):
        """
        Returns a Form class for use in the admin add view. This is used by
        add_view and change_view.
        """
        if self.declared_fieldsets:
            fields = flatten_fieldsets(self.declared_fieldsets)
        else:
            fields = None
        if self.exclude is None:
            exclude = []
        else:
            exclude = list(self.exclude)
        defaults = {
            "form": self.form,
            "fields": fields,
            "exclude": exclude + kwargs.get("exclude", []),
            "formfield_callback": self.formfield_for_dbfield,
        }
        defaults.update(kwargs)
        return modelform_factory(self.model, **defaults)

    def get_formsets(self, request, obj=None):
        for inline in self.inline_instances:
            yield inline.get_formset(request, obj)
            
    def log_addition(self, request, object):
        """
        Log that an object has been successfully added. 
        
        The default implementation creates an admin LogEntry object.
        """
        from django.contrib.admin.models import LogEntry, ADDITION
        LogEntry.objects.log_action(
            user_id         = request.user.pk, 
            content_type_id = ContentType.objects.get_for_model(object).pk,
            object_id       = object.pk,
            object_repr     = force_unicode(object), 
            action_flag     = ADDITION
        )
        
    def log_change(self, request, object, message):
        """
        Log that an object has been successfully changed. 
        
        The default implementation creates an admin LogEntry object.
        """
        from django.contrib.admin.models import LogEntry, CHANGE
        LogEntry.objects.log_action(
            user_id         = request.user.pk, 
            content_type_id = ContentType.objects.get_for_model(object).pk, 
            object_id       = object.pk, 
            object_repr     = force_unicode(object), 
            action_flag     = CHANGE, 
            change_message  = message
        )
        
    def log_deletion(self, request, object, object_repr):
        """
        Log that an object has been successfully deleted. Note that since the
        object is deleted, it might no longer be safe to call *any* methods
        on the object, hence this method getting object_repr.
        
        The default implementation creates an admin LogEntry object.
        """
        from django.contrib.admin.models import LogEntry, DELETION
        LogEntry.objects.log_action(
            user_id         = request.user.id, 
            content_type_id = ContentType.objects.get_for_model(self.model).pk, 
            object_id       = object.pk, 
            object_repr     = object_repr,
            action_flag     = DELETION
        )
        
    
    def construct_change_message(self, request, form, formsets):
        """
        Construct a change message from a changed object.
        """
        change_message = []
        if form.changed_data:
            change_message.append(_('Changed %s.') % get_text_list(form.changed_data, _('and')))

        if formsets:
            for formset in formsets:
                for added_object in formset.new_objects:
                    change_message.append(_('Added %(name)s "%(object)s".')
                                          % {'name': added_object._meta.verbose_name,
                                             'object': force_unicode(added_object)})
                for changed_object, changed_fields in formset.changed_objects:
                    change_message.append(_('Changed %(list)s for %(name)s "%(object)s".')
                                          % {'list': get_text_list(changed_fields, _('and')),
                                             'name': changed_object._meta.verbose_name,
                                             'object': force_unicode(changed_object)})
                for deleted_object in formset.deleted_objects:
                    change_message.append(_('Deleted %(name)s "%(object)s".')
                                          % {'name': deleted_object._meta.verbose_name,
                                             'object': force_unicode(deleted_object)})
        change_message = ' '.join(change_message)
        return change_message or _('No fields changed.')
    
    def message_user(self, request, message):
        """
        Send a message to the user. The default implementation 
        posts a message using the auth Message object.
        """
        request.user.message_set.create(message=message)

    def save_form(self, request, form, change):
        """
        Given a ModelForm return an unsaved instance. ``change`` is True if
        the object is being changed, and False if it's being added.
        """
        return form.save(commit=False)
    
    def save_model(self, request, obj, form, change):
        """
        Given a model instance save it to the database.
        """
        obj.save()

    def save_formset(self, request, form, formset, change):
        """
        Given an inline formset save it to the database.
        """
        formset.save()

    def render_change_form(self, request, context, add=False, change=False, form_url='', obj=None):
        opts = self.model._meta
        app_label = opts.app_label
        ordered_objects = opts.get_ordered_objects()
        context.update({
            'add': add,
            'change': change,
            'has_add_permission': self.has_add_permission(request),
            'has_change_permission': self.has_change_permission(request, obj),
            'has_delete_permission': self.has_delete_permission(request, obj),
            'has_file_field': True, # FIXME - this should check if form or formsets have a FileField,
            'has_absolute_url': hasattr(self.model, 'get_absolute_url'),
            'ordered_objects': ordered_objects,
            'form_url': mark_safe(form_url),
            'opts': opts,
            'content_type_id': ContentType.objects.get_for_model(self.model).id,
            'save_as': self.save_as,
            'save_on_top': self.save_on_top,
            'root_path': self.admin_site.root_path,
        })
        return render_to_response(self.change_form_template or [
            "admin/%s/%s/change_form.html" % (app_label, opts.object_name.lower()),
            "admin/%s/change_form.html" % app_label,
            "admin/change_form.html"
        ], context, context_instance=template.RequestContext(request))
    
    def response_add(self, request, obj, post_url_continue='../%s/'):
        """
        Determines the HttpResponse for the add_view stage.
        """
        opts = obj._meta
        pk_value = obj._get_pk_val()
        
        msg = _('The %(name)s "%(obj)s" was added successfully.') % {'name': force_unicode(opts.verbose_name), 'obj': force_unicode(obj)}
        # Here, we distinguish between different save types by checking for
        # the presence of keys in request.POST.
        if request.POST.has_key("_continue"):
            self.message_user(request, msg + ' ' + _("You may edit it again below."))
            if request.POST.has_key("_popup"):
                post_url_continue += "?_popup=1"
            return HttpResponseRedirect(post_url_continue % pk_value)
        
        if request.POST.has_key("_popup"):
            return HttpResponse('<script type="text/javascript">opener.dismissAddAnotherPopup(window, "%s", "%s");</script>' % \
                # escape() calls force_unicode.
                (escape(pk_value), escape(obj)))
        elif request.POST.has_key("_addanother"):
            self.message_user(request, msg + ' ' + (_("You may add another %s below.") % force_unicode(opts.verbose_name)))
            return HttpResponseRedirect(request.path)
        else:
            self.message_user(request, msg)

            # Figure out where to redirect. If the user has change permission,
            # redirect to the change-list page for this object. Otherwise,
            # redirect to the admin index.
            if self.has_change_permission(request, None):
                post_url = '../'
            else:
                post_url = '../../../'
            return HttpResponseRedirect(post_url)
    
    def response_change(self, request, obj):
        """
        Determines the HttpResponse for the change_view stage.
        """
        opts = obj._meta
        pk_value = obj._get_pk_val()
        
        msg = _('The %(name)s "%(obj)s" was changed successfully.') % {'name': force_unicode(opts.verbose_name), 'obj': force_unicode(obj)}
        if request.POST.has_key("_continue"):
            self.message_user(request, msg + ' ' + _("You may edit it again below."))
            if request.REQUEST.has_key('_popup'):
                return HttpResponseRedirect(request.path + "?_popup=1")
            else:
                return HttpResponseRedirect(request.path)
        elif request.POST.has_key("_saveasnew"):
            msg = _('The %(name)s "%(obj)s" was added successfully. You may edit it again below.') % {'name': force_unicode(opts.verbose_name), 'obj': obj}
            self.message_user(request, msg)
            return HttpResponseRedirect("../%s/" % pk_value)
        elif request.POST.has_key("_addanother"):
            self.message_user(request, msg + ' ' + (_("You may add another %s below.") % force_unicode(opts.verbose_name)))
            return HttpResponseRedirect("../add/")
        else:
            self.message_user(request, msg)
            return HttpResponseRedirect("../")

    def add_view(self, request, form_url='', extra_context=None):
        "The 'add' admin view for this model."
        model = self.model
        opts = model._meta

        if not self.has_add_permission(request):