from __future__ import unicode_literals import datetime import decimal from collections import defaultdict from django.contrib.auth import get_permission_codename from django.core.exceptions import FieldDoesNotExist from django.core.urlresolvers import NoReverseMatch, reverse from django.db import models from django.db.models.constants import LOOKUP_SEP from django.db.models.deletion import Collector from django.db.models.sql.constants import QUERY_TERMS from django.forms.forms import pretty_name from django.utils import formats, six, timezone from django.utils.encoding import force_str, force_text, smart_text from django.utils.html import format_html from django.utils.text import capfirst from django.utils.translation import ungettext def lookup_needs_distinct(opts, lookup_path): """ Returns True if 'distinct()' should be used to query the given lookup path. """ lookup_fields = lookup_path.split('__') # Remove the last item of the lookup path if it is a query term if lookup_fields[-1] in QUERY_TERMS: lookup_fields = lookup_fields[:-1] # Now go through the fields (following all relations) and look for an m2m for field_name in lookup_fields: field = opts.get_field(field_name) if hasattr(field, 'get_path_info'): # This field is a relation, update opts to follow the relation path_info = field.get_path_info() opts = path_info[-1].to_opts if any(path.m2m for path in path_info): # This field is a m2m relation so we know we need to call distinct return True return False def prepare_lookup_value(key, value): """ Returns a lookup value prepared to be used in queryset filtering. """ # if key ends with __in, split parameter into separate values if key.endswith('__in'): value = value.split(',') # if key ends with __isnull, special case '' and the string literals 'false' and '0' if key.endswith('__isnull'): if value.lower() in ('', 'false', '0'): value = False else: value = True return value def quote(s): """ Ensure that primary key values do not confuse the admin URLs by escaping any '/', '_' and ':' and similarly problematic characters. Similar to urllib.quote, except that the quoting is slightly different so that it doesn't get automatically unquoted by the Web browser. """ if not isinstance(s, six.string_types): return s res = list(s) for i in range(len(res)): c = res[i] if c in """:/_#?;@&=+$,"[]<>%\\""": res[i] = '_%02X' % ord(c) return ''.join(res) def unquote(s): """ Undo the effects of quote(). Based heavily on urllib.unquote(). """ mychr = chr myatoi = int list = s.split('_') res = [list[0]] myappend = res.append del list[0] for item in list: if item[1:2]: try: myappend(mychr(myatoi(item[:2], 16)) + item[2:]) except ValueError: myappend('_' + item) else: myappend('_' + item) return "".join(res) def flatten(fields): """Returns a list which is a single level of flattening of the original list.""" flat = [] for field in fields: if isinstance(field, (list, tuple)): flat.extend(field) else: flat.append(field) return flat def flatten_fieldsets(fieldsets): """Returns a list of field names from an admin fieldsets structure.""" field_names = [] for name, opts in fieldsets: field_names.extend( flatten(opts['fields']) ) return field_names def get_deleted_objects(objs, opts, user, admin_site, using): """ Find all objects related to ``objs`` that should also be deleted. ``objs`` must be a homogeneous iterable of objects (e.g. a QuerySet). Returns a nested list of strings suitable for display in the template with the ``unordered_list`` filter. """ collector = NestedObjects(using=using) collector.collect(objs) perms_needed = set() def format_callback(obj): has_admin = obj.__class__ in admin_site._registry opts = obj._meta no_edit_link = '%s: %s' % (capfirst(opts.verbose_name), force_text(obj)) if has_admin: try: admin_url = reverse('%s:%s_%s_change' % (admin_site.name, opts.app_label, opts.model_name), None, (quote(obj._get_pk_val()),)) except NoReverseMatch: # Change url doesn't exist -- don't display link to edit return no_edit_link p = '%s.%s' % (opts.app_label, get_permission_codename('delete', opts)) if not user.has_perm(p): perms_needed.add(opts.verbose_name) # Display a link to the admin page. return format_html('{}: {}', capfirst(opts.verbose_name), admin_url, obj) else: # Don't display link to edit, because it either has no # admin or is edited inline. return no_edit_link to_delete = collector.nested(format_callback) protected = [format_callback(obj) for obj in collector.protected] return to_delete, collector.model_count, perms_needed, protected class NestedObjects(Collector): def __init__(self, *args, **kwargs): super(NestedObjects, self).__init__(*args, **kwargs) self.edges = {} # {from_instance: [to_instances]} self.protected = set() self.model_count = defaultdict(int) def add_edge(self, source, target): self.edges.setdefault(source, []).append(target) def collect(self, objs, source=None, source_attr=None, **kwargs): for obj in objs: if source_attr and not source_attr.endswith('+'): related_name = source_attr % { 'class': source._meta.model_name, 'app_label': source._meta.app_label, } self.add_edge(getattr(obj, related_name), obj) else: self.add_edge(None, obj) self.model_count[obj._meta.verbose_name_plural] += 1 try: return super(NestedObjects, self).collect(objs, source_attr=source_attr, **kwargs) except models.ProtectedError as e: self.protected.update(e.protected_objects) def related_objects(self, related, objs): qs = super(NestedObjects, self).related_objects(related, objs) return qs.select_related(related.field.name) def _nested(self, obj, seen, format_callback): if obj in seen: return [] seen.add(obj) children = [] for child in self.edges.get(obj, ()): children.extend(self._nested(child, seen, format_callback)) if format_callback: ret = [format_callback(obj)] else: ret = [obj] if children: ret.append(children) return ret def nested(self, format_callback=None): """ Return the graph as a nested list. """ seen = set() roots = [] for root in self.edges.get(None, ()): roots.extend(self._nested(root, seen, format_callback)) return roots def can_fast_delete(self, *args, **kwargs): """ We always want to load the objects into memory so that we can display them to the user in confirm page. """ return False def model_format_dict(obj): """ Return a `dict` with keys 'verbose_name' and 'verbose_name_plural', typically for use with string formatting. `obj` may be a `Model` instance, `Model` subclass, or `QuerySet` instance. """ if isinstance(obj, (models.Model, models.base.ModelBase)): opts = obj._meta elif isinstance(obj, models.query.QuerySet): opts = obj.model._meta else: opts = obj return { 'verbose_name': force_text(opts.verbose_name), 'verbose_name_plural': force_text(opts.verbose_name_plural) } def model_ngettext(obj, n=None): """ Return the appropriate `verbose_name` or `verbose_name_plural` value for `obj` depending on the count `n`. `obj` may be a `Model` instance, `Model` subclass, or `QuerySet` instance. If `obj` is a `QuerySet` instance, `n` is optional and the length of the `QuerySet` is used. """ if isinstance(obj, models.query.QuerySet): if n is None: n = obj.count() obj = obj.model d = model_format_dict(obj) singular, plural = d["verbose_name"], d["verbose_name_plural"] return ungettext(singular, plural, n or 0) def lookup_field(name, obj, model_admin=None): opts = obj._meta try: f = _get_non_gfk_field(opts, name) except FieldDoesNotExist: # For non-field values, the value is either a method, property or # returned via a callable. if callable(name): attr = name value = attr(obj) elif (model_admin is not None and hasattr(model_admin, name) and not name == '__str__' and not name == '__unicode__'): attr = getattr(model_admin, name) value = attr(obj) else: attr = getattr(obj, name) if callable(attr): value = attr() else: value = attr f = None else: attr = None value = getattr(obj, name) return f, attr, value def _get_non_gfk_field(opts, name): """ For historical reasons, the admin app relies on GenericForeignKeys as being "not found" by get_field(). This could likely be cleaned up. """ field = opts.get_field(name) if field.is_relation and field.many_to_one and not field.related_model: raise FieldDoesNotExist() return field def label_for_field(name, model, model_admin=None, return_attr=False): """ Returns a sensible label for a field name. The name can be a callable, property (but not created with @property decorator) or the name of an object's attribute, as well as a genuine fields. If return_attr is True, the resolved attribute (which could be a callable) is also returned. This will be None if (and only if) the name refers to a field. """ attr = None try: field = _get_non_gfk_field(model._meta, name) try: label = field.verbose_name except AttributeError: # field is likely a ForeignObjectRel label = field.related_model._meta.verbose_name except FieldDoesNotExist: if name == "__unicode__": label = force_text(model._meta.verbose_name) attr = six.text_type elif name == "__str__": label = force_str(model._meta.verbose_name) attr = bytes else: if callable(name): attr = name elif model_admin is not None and hasattr(model_admin, name): attr = getattr(model_admin, name) elif hasattr(model, name): attr = getattr(model, name) else: message = "Unable to lookup '%s' on %s" % (name, model._meta.object_name) if model_admin: message += " or %s" % (model_admin.__class__.__name__,) raise AttributeError(message) if hasattr(attr, "short_description"): label = attr.short_description elif (isinstance(attr, property) and hasattr(attr, "fget") and hasattr(attr.fget, "short_description")): label = attr.fget.short_description elif callable(attr): if attr.__name__ == "": label = "--" else: label = pretty_name(attr.__name__) else: label = pretty_name(name) if return_attr: return (label, attr) else: return label def help_text_for_field(name, model): help_text = "" try: field = _get_non_gfk_field(model._meta, name) except FieldDoesNotExist: pass else: if hasattr(field, 'help_text'): help_text = field.help_text return smart_text(help_text) def display_for_field(value, field): from django.contrib.admin.templatetags.admin_list import _boolean_icon from django.contrib.admin.views.main import EMPTY_CHANGELIST_VALUE if field.flatchoices: return dict(field.flatchoices).get(value, EMPTY_CHANGELIST_VALUE) # NullBooleanField needs special-case null-handling, so it comes # before the general null test. elif isinstance(field, models.BooleanField) or isinstance(field, models.NullBooleanField): return _boolean_icon(value) elif value is None: return EMPTY_CHANGELIST_VALUE elif isinstance(field, models.DateTimeField): return formats.localize(timezone.template_localtime(value)) elif isinstance(field, (models.DateField, models.TimeField)): return formats.localize(value) elif isinstance(field, models.DecimalField): return formats.number_format(value, field.decimal_places) elif isinstance(field, (models.IntegerField, models.FloatField)): return formats.number_format(value) elif isinstance(field, models.FileField) and value: return format_html('{}', value.url, value) else: return smart_text(value) def display_for_value(value, boolean=False): from django.contrib.admin.templatetags.admin_list import _boolean_icon from django.contrib.admin.views.main import EMPTY_CHANGELIST_VALUE if boolean: return _boolean_icon(value) elif value is None: return EMPTY_CHANGELIST_VALUE elif isinstance(value, datetime.datetime): return formats.localize(timezone.template_localtime(value)) elif isinstance(value, (datetime.date, datetime.time)): return formats.localize(value) elif isinstance(value, six.integer_types + (decimal.Decimal, float)): return formats.number_format(value) else: return smart_text(value) class NotRelationField(Exception): pass def get_model_from_relation(field): if hasattr(field, 'get_path_info'): return field.get_path_info()[-1].to_opts.model else: raise NotRelationField def reverse_field_path(model, path): """ Create a reversed field path. E.g. Given (Order, "user__groups"), return (Group, "user__order"). Final field must be a related model, not a data field. """ reversed_path = [] parent = model pieces = path.split(LOOKUP_SEP) for piece in pieces: field = parent._meta.get_field(piece) # skip trailing data field if extant: if len(reversed_path) == len(pieces) - 1: # final iteration try: get_model_from_relation(field) except NotRelationField: break # Field should point to another model if field.is_relation and not (field.auto_created and not field.concrete): related_name = field.related_query_name() parent = field.remote_field.model else: related_name = field.field.name parent = field.related_model reversed_path.insert(0, related_name) return (parent, LOOKUP_SEP.join(reversed_path)) def get_fields_from_path(model, path): """ Return list of Fields given path relative to model. e.g. (ModelX, "user__groups__name") -> [ , , , ] """ pieces = path.split(LOOKUP_SEP) fields = [] for piece in pieces: if fields: parent = get_model_from_relation(fields[-1]) else: parent = model fields.append(parent._meta.get_field(piece)) return fields def remove_trailing_data_field(fields): """ Discard trailing non-relation field if extant. """ try: get_model_from_relation(fields[-1]) except NotRelationField: fields = fields[:-1] return fields