381 lines
12 KiB
Python
381 lines
12 KiB
Python
from copy import copy
|
|
from itertools import repeat
|
|
import inspect
|
|
|
|
from django.conf import settings
|
|
from django.utils import timezone
|
|
from django.utils.functional import cached_property
|
|
from django.utils.six.moves import xrange
|
|
|
|
|
|
class RegisterLookupMixin(object):
|
|
def _get_lookup(self, lookup_name):
|
|
try:
|
|
return self.class_lookups[lookup_name]
|
|
except KeyError:
|
|
# To allow for inheritance, check parent class' class_lookups.
|
|
for parent in inspect.getmro(self.__class__):
|
|
if 'class_lookups' not in parent.__dict__:
|
|
continue
|
|
if lookup_name in parent.class_lookups:
|
|
return parent.class_lookups[lookup_name]
|
|
except AttributeError:
|
|
# This class didn't have any class_lookups
|
|
pass
|
|
if hasattr(self, 'output_type'):
|
|
return self.output_type.get_lookup(lookup_name)
|
|
return None
|
|
|
|
def get_lookup(self, lookup_name):
|
|
found = self._get_lookup(lookup_name)
|
|
if found is not None and not issubclass(found, Lookup):
|
|
return None
|
|
return found
|
|
|
|
def get_transform(self, lookup_name):
|
|
found = self._get_lookup(lookup_name)
|
|
if found is not None and not issubclass(found, Transform):
|
|
return None
|
|
return found
|
|
|
|
@classmethod
|
|
def register_lookup(cls, lookup):
|
|
if 'class_lookups' not in cls.__dict__:
|
|
cls.class_lookups = {}
|
|
cls.class_lookups[lookup.lookup_name] = lookup
|
|
|
|
@classmethod
|
|
def _unregister_lookup(cls, lookup):
|
|
"""
|
|
Removes given lookup from cls lookups. Meant to be used in
|
|
tests only.
|
|
"""
|
|
del cls.class_lookups[lookup.lookup_name]
|
|
|
|
|
|
class Transform(RegisterLookupMixin):
|
|
def __init__(self, lhs, lookups):
|
|
self.lhs = lhs
|
|
self.init_lookups = lookups[:]
|
|
|
|
def as_sql(self, qn, connection):
|
|
raise NotImplementedError
|
|
|
|
@cached_property
|
|
def output_type(self):
|
|
return self.lhs.output_type
|
|
|
|
def relabeled_clone(self, relabels):
|
|
return self.__class__(self.lhs.relabeled_clone(relabels))
|
|
|
|
def get_group_by_cols(self):
|
|
return self.lhs.get_group_by_cols()
|
|
|
|
|
|
class Lookup(RegisterLookupMixin):
|
|
lookup_name = None
|
|
|
|
def __init__(self, lhs, rhs):
|
|
self.lhs, self.rhs = lhs, rhs
|
|
self.rhs = self.get_prep_lookup()
|
|
|
|
def get_prep_lookup(self):
|
|
return self.lhs.output_type.get_prep_lookup(self.lookup_name, self.rhs)
|
|
|
|
def get_db_prep_lookup(self, value, connection):
|
|
return (
|
|
'%s', self.lhs.output_type.get_db_prep_lookup(
|
|
self.lookup_name, value, connection, prepared=True))
|
|
|
|
def process_lhs(self, qn, connection, lhs=None):
|
|
lhs = lhs or self.lhs
|
|
return qn.compile(lhs)
|
|
|
|
def process_rhs(self, qn, connection):
|
|
value = self.rhs
|
|
# Due to historical reasons there are a couple of different
|
|
# ways to produce sql here. get_compiler is likely a Query
|
|
# instance, _as_sql QuerySet and as_sql just something with
|
|
# as_sql. Finally the value can of course be just plain
|
|
# Python value.
|
|
if hasattr(value, 'get_compiler'):
|
|
value = value.get_compiler(connection=connection)
|
|
if hasattr(value, 'as_sql'):
|
|
sql, params = qn.compile(value)
|
|
return '(' + sql + ')', params
|
|
if hasattr(value, '_as_sql'):
|
|
sql, params = value._as_sql(connection=connection)
|
|
return '(' + sql + ')', params
|
|
else:
|
|
return self.get_db_prep_lookup(value, connection)
|
|
|
|
def rhs_is_direct_value(self):
|
|
return not(
|
|
hasattr(self.rhs, 'as_sql') or
|
|
hasattr(self.rhs, '_as_sql') or
|
|
hasattr(self.rhs, 'get_compiler'))
|
|
|
|
def relabeled_clone(self, relabels):
|
|
new = copy(self)
|
|
new.lhs = new.lhs.relabeled_clone(relabels)
|
|
if hasattr(new.rhs, 'relabeled_clone'):
|
|
new.rhs = new.rhs.relabeled_clone(relabels)
|
|
return new
|
|
|
|
def get_group_by_cols(self):
|
|
cols = self.lhs.get_group_by_cols()
|
|
if hasattr(self.rhs, 'get_group_by_cols'):
|
|
cols.extend(self.rhs.get_group_by_cols())
|
|
return cols
|
|
|
|
def as_sql(self, qn, connection):
|
|
raise NotImplementedError
|
|
|
|
|
|
class BuiltinLookup(Lookup):
|
|
def process_lhs(self, qn, connection, lhs=None):
|
|
lhs_sql, params = super(BuiltinLookup, self).process_lhs(
|
|
qn, connection, lhs)
|
|
field_internal_type = self.lhs.output_type.get_internal_type()
|
|
db_type = self.lhs.output_type.db_type(connection=connection)
|
|
lhs_sql = connection.ops.field_cast_sql(
|
|
db_type, field_internal_type) % lhs_sql
|
|
lhs_sql = connection.ops.lookup_cast(self.lookup_name) % lhs_sql
|
|
return lhs_sql, params
|
|
|
|
def as_sql(self, qn, connection):
|
|
lhs_sql, params = self.process_lhs(qn, connection)
|
|
rhs_sql, rhs_params = self.process_rhs(qn, connection)
|
|
params.extend(rhs_params)
|
|
rhs_sql = self.get_rhs_op(connection, rhs_sql)
|
|
return '%s %s' % (lhs_sql, rhs_sql), params
|
|
|
|
def get_rhs_op(self, connection, rhs):
|
|
return connection.operators[self.lookup_name] % rhs
|
|
|
|
|
|
default_lookups = {}
|
|
|
|
|
|
class Exact(BuiltinLookup):
|
|
lookup_name = 'exact'
|
|
default_lookups['exact'] = Exact
|
|
|
|
|
|
class IExact(BuiltinLookup):
|
|
lookup_name = 'iexact'
|
|
default_lookups['iexact'] = IExact
|
|
|
|
|
|
class Contains(BuiltinLookup):
|
|
lookup_name = 'contains'
|
|
default_lookups['contains'] = Contains
|
|
|
|
|
|
class IContains(BuiltinLookup):
|
|
lookup_name = 'icontains'
|
|
default_lookups['icontains'] = IContains
|
|
|
|
|
|
class GreaterThan(BuiltinLookup):
|
|
lookup_name = 'gt'
|
|
default_lookups['gt'] = GreaterThan
|
|
|
|
|
|
class GreaterThanOrEqual(BuiltinLookup):
|
|
lookup_name = 'gte'
|
|
default_lookups['gte'] = GreaterThanOrEqual
|
|
|
|
|
|
class LessThan(BuiltinLookup):
|
|
lookup_name = 'lt'
|
|
default_lookups['lt'] = LessThan
|
|
|
|
|
|
class LessThanOrEqual(BuiltinLookup):
|
|
lookup_name = 'lte'
|
|
default_lookups['lte'] = LessThanOrEqual
|
|
|
|
|
|
class In(BuiltinLookup):
|
|
lookup_name = 'in'
|
|
|
|
def get_db_prep_lookup(self, value, connection):
|
|
params = self.lhs.output_type.get_db_prep_lookup(
|
|
self.lookup_name, value, connection, prepared=True)
|
|
if not params:
|
|
# TODO: check why this leads to circular import
|
|
from django.db.models.sql.datastructures import EmptyResultSet
|
|
raise EmptyResultSet
|
|
placeholder = '(' + ', '.join('%s' for p in params) + ')'
|
|
return (placeholder, params)
|
|
|
|
def get_rhs_op(self, connection, rhs):
|
|
return 'IN %s' % rhs
|
|
|
|
def as_sql(self, qn, connection):
|
|
max_in_list_size = connection.ops.max_in_list_size()
|
|
if self.rhs_is_direct_value() and (max_in_list_size and
|
|
len(self.rhs) > max_in_list_size):
|
|
rhs, rhs_params = self.process_rhs(qn, connection)
|
|
lhs, lhs_params = self.process_lhs(qn, connection)
|
|
in_clause_elements = ['(']
|
|
params = []
|
|
for offset in xrange(0, len(rhs_params), max_in_list_size):
|
|
if offset > 0:
|
|
in_clause_elements.append(' OR ')
|
|
in_clause_elements.append('%s IN (' % lhs)
|
|
params.extend(lhs_params)
|
|
group_size = min(len(rhs_params) - offset, max_in_list_size)
|
|
param_group = ', '.join(repeat('%s', group_size))
|
|
in_clause_elements.append(param_group)
|
|
in_clause_elements.append(')')
|
|
params.extend(rhs_params[offset: offset + max_in_list_size])
|
|
in_clause_elements.append(')')
|
|
return ''.join(in_clause_elements), params
|
|
else:
|
|
return super(In, self).as_sql(qn, connection)
|
|
|
|
|
|
default_lookups['in'] = In
|
|
|
|
|
|
class PatternLookup(BuiltinLookup):
|
|
def get_rhs_op(self, connection, rhs):
|
|
# Assume we are in startswith. We need to produce SQL like:
|
|
# col LIKE %s, ['thevalue%']
|
|
# For python values we can (and should) do that directly in Python,
|
|
# but if the value is for example reference to other column, then
|
|
# we need to add the % pattern match to the lookup by something like
|
|
# col LIKE othercol || '%%'
|
|
# So, for Python values we don't need any special pattern, but for
|
|
# SQL reference values we need the correct pattern added.
|
|
value = self.rhs
|
|
if (hasattr(value, 'get_compiler') or hasattr(value, 'as_sql')
|
|
or hasattr(value, '_as_sql')):
|
|
return connection.pattern_ops[self.lookup_name] % rhs
|
|
else:
|
|
return super(PatternLookup, self).get_rhs_op(connection, rhs)
|
|
|
|
|
|
class StartsWith(PatternLookup):
|
|
lookup_name = 'startswith'
|
|
default_lookups['startswith'] = StartsWith
|
|
|
|
|
|
class IStartsWith(PatternLookup):
|
|
lookup_name = 'istartswith'
|
|
default_lookups['istartswith'] = IStartsWith
|
|
|
|
|
|
class EndsWith(BuiltinLookup):
|
|
lookup_name = 'endswith'
|
|
default_lookups['endswith'] = EndsWith
|
|
|
|
|
|
class IEndsWith(BuiltinLookup):
|
|
lookup_name = 'iendswith'
|
|
default_lookups['iendswith'] = IEndsWith
|
|
|
|
|
|
class Between(BuiltinLookup):
|
|
def get_rhs_op(self, connection, rhs):
|
|
return "BETWEEN %s AND %s" % (rhs, rhs)
|
|
|
|
|
|
class Year(Between):
|
|
lookup_name = 'year'
|
|
default_lookups['year'] = Year
|
|
|
|
|
|
class Range(Between):
|
|
lookup_name = 'range'
|
|
default_lookups['range'] = Range
|
|
|
|
|
|
class DateLookup(BuiltinLookup):
|
|
def process_lhs(self, qn, connection, lhs=None):
|
|
from django.db.models import DateTimeField
|
|
lhs, params = super(DateLookup, self).process_lhs(qn, connection, lhs)
|
|
if isinstance(self.lhs.output_type, DateTimeField):
|
|
tzname = timezone.get_current_timezone_name() if settings.USE_TZ else None
|
|
sql, tz_params = connection.ops.datetime_extract_sql(self.extract_type, lhs, tzname)
|
|
return connection.ops.lookup_cast(self.lookup_name) % sql, tz_params
|
|
else:
|
|
return connection.ops.date_extract_sql(self.lookup_name, lhs), []
|
|
|
|
def get_rhs_op(self, connection, rhs):
|
|
return '= %s' % rhs
|
|
|
|
|
|
class Month(DateLookup):
|
|
lookup_name = 'month'
|
|
extract_type = 'month'
|
|
default_lookups['month'] = Month
|
|
|
|
|
|
class Day(DateLookup):
|
|
lookup_name = 'day'
|
|
extract_type = 'day'
|
|
default_lookups['day'] = Day
|
|
|
|
|
|
class WeekDay(DateLookup):
|
|
lookup_name = 'week_day'
|
|
extract_type = 'week_day'
|
|
default_lookups['week_day'] = WeekDay
|
|
|
|
|
|
class Hour(DateLookup):
|
|
lookup_name = 'hour'
|
|
extract_type = 'hour'
|
|
default_lookups['hour'] = Hour
|
|
|
|
|
|
class Minute(DateLookup):
|
|
lookup_name = 'minute'
|
|
extract_type = 'minute'
|
|
default_lookups['minute'] = Minute
|
|
|
|
|
|
class Second(DateLookup):
|
|
lookup_name = 'second'
|
|
extract_type = 'second'
|
|
default_lookups['second'] = Second
|
|
|
|
|
|
class IsNull(BuiltinLookup):
|
|
lookup_name = 'isnull'
|
|
|
|
def as_sql(self, qn, connection):
|
|
sql, params = qn.compile(self.lhs)
|
|
if self.rhs:
|
|
return "%s IS NULL" % sql, params
|
|
else:
|
|
return "%s IS NOT NULL" % sql, params
|
|
default_lookups['isnull'] = IsNull
|
|
|
|
|
|
class Search(BuiltinLookup):
|
|
lookup_name = 'search'
|
|
default_lookups['search'] = Search
|
|
|
|
|
|
class Regex(BuiltinLookup):
|
|
lookup_name = 'regex'
|
|
|
|
def as_sql(self, qn, connection):
|
|
if self.lookup_name in connection.operators:
|
|
return super(Regex, self).as_sql(qn, connection)
|
|
else:
|
|
lhs, lhs_params = self.process_lhs(qn, connection)
|
|
rhs, rhs_params = self.process_rhs(qn, connection)
|
|
sql_template = connection.ops.regex_lookup(self.lookup_name)
|
|
return sql_template % (lhs, rhs), lhs_params + rhs_params
|
|
default_lookups['regex'] = Regex
|
|
|
|
|
|
class IRegex(Regex):
|
|
lookup_name = 'iregex'
|
|
default_lookups['iregex'] = IRegex
|