django1/django/contrib/admin/utils.py

504 lines
16 KiB
Python

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.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.
"""
field_name = lookup_path.split('__', 1)[0]
field = opts.get_field(field_name)
if hasattr(field, 'get_path_info') and any(path.m2m for path in field.get_path_info()):
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('{}: <a href="{}">{}</a>',
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__ == "<lambda>":
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.FloatField):
return formats.number_format(value)
elif isinstance(field, models.FileField) and value:
return format_html('<a href="{}">{}</a>', 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.rel.to
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") -> [
<django.db.models.fields.related.ForeignKey object at 0x...>,
<django.db.models.fields.related.ManyToManyField object at 0x...>,
<django.db.models.fields.CharField object at 0x...>,
]
"""
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
def get_limit_choices_to_from_path(model, path):
""" Return Q object for limiting choices if applicable.
If final model in path is linked via a ForeignKey or ManyToManyField which
has a ``limit_choices_to`` attribute, return it as a Q object.
"""
fields = get_fields_from_path(model, path)
fields = remove_trailing_data_field(fields)
get_limit_choices_to = (
fields and hasattr(fields[-1], 'rel') and
getattr(fields[-1].rel, 'get_limit_choices_to', None))
if not get_limit_choices_to:
return models.Q() # empty Q
limit_choices_to = get_limit_choices_to()
if isinstance(limit_choices_to, models.Q):
return limit_choices_to # already a Q
else:
return models.Q(**limit_choices_to) # convert dict to Q