django1/django/contrib/databrowse/datastructures.py

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"""
These classes are light wrappers around Django's database API that provide
convenience functionality and permalink functions for the databrowse app.
"""
from __future__ import unicode_literals
from django.db import models
from django.utils import formats
from django.utils.text import capfirst
from django.utils.encoding import smart_text, force_str, iri_to_uri
from django.db.models.query import QuerySet
from django.utils.encoding import python_2_unicode_compatible
EMPTY_VALUE = '(None)'
DISPLAY_SIZE = 100
class EasyModel(object):
def __init__(self, site, model):
self.site = site
self.model = model
self.model_list = list(site.registry.keys())
self.verbose_name = model._meta.verbose_name
self.verbose_name_plural = model._meta.verbose_name_plural
def __repr__(self):
return force_str('<EasyModel for %s>' % self.model._meta.object_name)
def model_databrowse(self):
"Returns the ModelDatabrowse class for this model."
return self.site.registry[self.model]
def url(self):
return '%s%s/%s/' % (self.site.root_url, self.model._meta.app_label, self.model._meta.module_name)
def objects(self, **kwargs):
return self.get_query_set().filter(**kwargs)
def get_query_set(self):
easy_qs = self.model._default_manager.get_query_set()._clone(klass=EasyQuerySet)
easy_qs._easymodel = self
return easy_qs
def object_by_pk(self, pk):
return EasyInstance(self, self.model._default_manager.get(pk=pk))
def sample_objects(self):
for obj in self.model._default_manager.all()[:3]:
yield EasyInstance(self, obj)
def field(self, name):
try:
f = self.model._meta.get_field(name)
except models.FieldDoesNotExist:
return None
return EasyField(self, f)
def fields(self):
return [EasyField(self, f) for f in (self.model._meta.fields + self.model._meta.many_to_many)]
class EasyField(object):
def __init__(self, easy_model, field):
self.model, self.field = easy_model, field
def __repr__(self):
return force_str('<EasyField for %s.%s>' % (self.model.model._meta.object_name, self.field.name))
def choices(self):
for value, label in self.field.choices:
yield EasyChoice(self.model, self, value, label)
def url(self):
if self.field.choices:
return '%s%s/%s/%s/' % (self.model.site.root_url, self.model.model._meta.app_label, self.model.model._meta.module_name, self.field.name)
elif self.field.rel:
return '%s%s/%s/' % (self.model.site.root_url, self.model.model._meta.app_label, self.model.model._meta.module_name)
class EasyChoice(object):
def __init__(self, easy_model, field, value, label):
self.model, self.field = easy_model, field
self.value, self.label = value, label
def __repr__(self):
return force_str('<EasyChoice for %s.%s>' % (self.model.model._meta.object_name, self.field.name))
def url(self):
return '%s%s/%s/%s/%s/' % (self.model.site.root_url, self.model.model._meta.app_label, self.model.model._meta.module_name, self.field.field.name, iri_to_uri(self.value))
@python_2_unicode_compatible
class EasyInstance(object):
def __init__(self, easy_model, instance):
self.model, self.instance = easy_model, instance
def __repr__(self):
return force_str('<EasyInstance for %s (%s)>' % (self.model.model._meta.object_name, self.instance._get_pk_val()))
def __str__(self):
val = smart_text(self.instance)
if len(val) > DISPLAY_SIZE:
return val[:DISPLAY_SIZE] + '...'
return val
def pk(self):
return self.instance._get_pk_val()
def url(self):
return '%s%s/%s/objects/%s/' % (self.model.site.root_url, self.model.model._meta.app_label, self.model.model._meta.module_name, iri_to_uri(self.pk()))
def fields(self):
"""
Generator that yields EasyInstanceFields for each field in this
EasyInstance's model.
"""
for f in self.model.model._meta.fields + self.model.model._meta.many_to_many:
yield EasyInstanceField(self.model, self, f)
def related_objects(self):
"""
Generator that yields dictionaries of all models that have this
EasyInstance's model as a ForeignKey or ManyToManyField, along with
lists of related objects.
"""
for rel_object in self.model.model._meta.get_all_related_objects() + self.model.model._meta.get_all_related_many_to_many_objects():
if rel_object.model not in self.model.model_list:
continue # Skip models that aren't in the model_list
em = EasyModel(self.model.site, rel_object.model)
yield {
'model': em,
'related_field': rel_object.field.verbose_name,
'object_list': [EasyInstance(em, i) for i in getattr(self.instance, rel_object.get_accessor_name()).all()],
}
class EasyInstanceField(object):
def __init__(self, easy_model, instance, field):
self.model, self.field, self.instance = easy_model, field, instance
self.raw_value = getattr(instance.instance, field.name)
def __repr__(self):
return force_str('<EasyInstanceField for %s.%s>' % (self.model.model._meta.object_name, self.field.name))
def values(self):
"""
Returns a list of values for this field for this instance. It's a list
so we can accomodate many-to-many fields.
"""
# This import is deliberately inside the function because it causes
# some settings to be imported, and we don't want to do that at the
# module level.
if self.field.rel:
if isinstance(self.field.rel, models.ManyToOneRel):
objs = getattr(self.instance.instance, self.field.name)
elif isinstance(self.field.rel, models.ManyToManyRel): # ManyToManyRel
return list(getattr(self.instance.instance, self.field.name).all())
elif self.field.choices:
objs = dict(self.field.choices).get(self.raw_value, EMPTY_VALUE)
elif isinstance(self.field, models.DateField) or isinstance(self.field, models.TimeField):
if self.raw_value:
if isinstance(self.field, models.DateTimeField):
objs = capfirst(formats.date_format(self.raw_value, 'DATETIME_FORMAT'))
elif isinstance(self.field, models.TimeField):
objs = capfirst(formats.time_format(self.raw_value, 'TIME_FORMAT'))
else:
objs = capfirst(formats.date_format(self.raw_value, 'DATE_FORMAT'))
else:
objs = EMPTY_VALUE
elif isinstance(self.field, models.BooleanField) or isinstance(self.field, models.NullBooleanField):
objs = {True: 'Yes', False: 'No', None: 'Unknown'}[self.raw_value]
else:
objs = self.raw_value
return [objs]
def urls(self):
"Returns a list of (value, URL) tuples."
# First, check the urls() method for each plugin.
plugin_urls = []
for plugin_name, plugin in self.model.model_databrowse().plugins.items():
urls = plugin.urls(plugin_name, self)
if urls is not None:
return zip(self.values(), urls)
if self.field.rel:
m = EasyModel(self.model.site, self.field.rel.to)
if self.field.rel.to in self.model.model_list:
lst = []
for value in self.values():
if value is None:
continue
url = '%s%s/%s/objects/%s/' % (self.model.site.root_url, m.model._meta.app_label, m.model._meta.module_name, iri_to_uri(value._get_pk_val()))
lst.append((smart_text(value), url))
else:
lst = [(value, None) for value in self.values()]
elif self.field.choices:
lst = []
for value in self.values():
url = '%s%s/%s/fields/%s/%s/' % (self.model.site.root_url, self.model.model._meta.app_label, self.model.model._meta.module_name, self.field.name, iri_to_uri(self.raw_value))
lst.append((value, url))
elif isinstance(self.field, models.URLField):
val = list(self.values())[0]
lst = [(val, iri_to_uri(val))]
else:
lst = [(list(self.values())[0], None)]
return lst
class EasyQuerySet(QuerySet):
"""
When creating (or cloning to) an `EasyQuerySet`, make sure to set the
`_easymodel` variable to the related `EasyModel`.
"""
def iterator(self, *args, **kwargs):
for obj in super(EasyQuerySet, self).iterator(*args, **kwargs):
yield EasyInstance(self._easymodel, obj)
def _clone(self, *args, **kwargs):
c = super(EasyQuerySet, self)._clone(*args, **kwargs)
c._easymodel = self._easymodel
return c