Your IP : 13.58.191.60
# sql/cache_key.py
# Copyright (C) 2005-2024 the SQLAlchemy authors and contributors
# <see AUTHORS file>
#
# This module is part of SQLAlchemy and is released under
# the MIT License: https://www.opensource.org/licenses/mit-license.php
from __future__ import annotations
import enum
from itertools import zip_longest
import typing
from typing import Any
from typing import Callable
from typing import Dict
from typing import Iterable
from typing import Iterator
from typing import List
from typing import MutableMapping
from typing import NamedTuple
from typing import Optional
from typing import Sequence
from typing import Tuple
from typing import Union
from .visitors import anon_map
from .visitors import HasTraversalDispatch
from .visitors import HasTraverseInternals
from .visitors import InternalTraversal
from .visitors import prefix_anon_map
from .. import util
from ..inspection import inspect
from ..util import HasMemoized
from ..util.typing import Literal
from ..util.typing import Protocol
if typing.TYPE_CHECKING:
from .elements import BindParameter
from .elements import ClauseElement
from .elements import ColumnElement
from .visitors import _TraverseInternalsType
from ..engine.interfaces import _CoreSingleExecuteParams
class _CacheKeyTraversalDispatchType(Protocol):
def __call__(
s, self: HasCacheKey, visitor: _CacheKeyTraversal
) -> _CacheKeyTraversalDispatchTypeReturn: ...
class CacheConst(enum.Enum):
NO_CACHE = 0
NO_CACHE = CacheConst.NO_CACHE
_CacheKeyTraversalType = Union[
"_TraverseInternalsType", Literal[CacheConst.NO_CACHE], Literal[None]
]
class CacheTraverseTarget(enum.Enum):
CACHE_IN_PLACE = 0
CALL_GEN_CACHE_KEY = 1
STATIC_CACHE_KEY = 2
PROPAGATE_ATTRS = 3
ANON_NAME = 4
(
CACHE_IN_PLACE,
CALL_GEN_CACHE_KEY,
STATIC_CACHE_KEY,
PROPAGATE_ATTRS,
ANON_NAME,
) = tuple(CacheTraverseTarget)
_CacheKeyTraversalDispatchTypeReturn = Sequence[
Tuple[
str,
Any,
Union[
Callable[..., Tuple[Any, ...]],
CacheTraverseTarget,
InternalTraversal,
],
]
]
class HasCacheKey:
"""Mixin for objects which can produce a cache key.
This class is usually in a hierarchy that starts with the
:class:`.HasTraverseInternals` base, but this is optional. Currently,
the class should be able to work on its own without including
:class:`.HasTraverseInternals`.
.. seealso::
:class:`.CacheKey`
:ref:`sql_caching`
"""
__slots__ = ()
_cache_key_traversal: _CacheKeyTraversalType = NO_CACHE
_is_has_cache_key = True
_hierarchy_supports_caching = True
"""private attribute which may be set to False to prevent the
inherit_cache warning from being emitted for a hierarchy of subclasses.
Currently applies to the :class:`.ExecutableDDLElement` hierarchy which
does not implement caching.
"""
inherit_cache: Optional[bool] = None
"""Indicate if this :class:`.HasCacheKey` instance should make use of the
cache key generation scheme used by its immediate superclass.
The attribute defaults to ``None``, which indicates that a construct has
not yet taken into account whether or not its appropriate for it to
participate in caching; this is functionally equivalent to setting the
value to ``False``, except that a warning is also emitted.
This flag can be set to ``True`` on a particular class, if the SQL that
corresponds to the object does not change based on attributes which
are local to this class, and not its superclass.
.. seealso::
:ref:`compilerext_caching` - General guideslines for setting the
:attr:`.HasCacheKey.inherit_cache` attribute for third-party or user
defined SQL constructs.
"""
__slots__ = ()
_generated_cache_key_traversal: Any
@classmethod
def _generate_cache_attrs(
cls,
) -> Union[_CacheKeyTraversalDispatchType, Literal[CacheConst.NO_CACHE]]:
"""generate cache key dispatcher for a new class.
This sets the _generated_cache_key_traversal attribute once called
so should only be called once per class.
"""
inherit_cache = cls.__dict__.get("inherit_cache", None)
inherit = bool(inherit_cache)
if inherit:
_cache_key_traversal = getattr(cls, "_cache_key_traversal", None)
if _cache_key_traversal is None:
try:
assert issubclass(cls, HasTraverseInternals)
_cache_key_traversal = cls._traverse_internals
except AttributeError:
cls._generated_cache_key_traversal = NO_CACHE
return NO_CACHE
assert _cache_key_traversal is not NO_CACHE, (
f"class {cls} has _cache_key_traversal=NO_CACHE, "
"which conflicts with inherit_cache=True"
)
# TODO: wouldn't we instead get this from our superclass?
# also, our superclass may not have this yet, but in any case,
# we'd generate for the superclass that has it. this is a little
# more complicated, so for the moment this is a little less
# efficient on startup but simpler.
return _cache_key_traversal_visitor.generate_dispatch(
cls,
_cache_key_traversal,
"_generated_cache_key_traversal",
)
else:
_cache_key_traversal = cls.__dict__.get(
"_cache_key_traversal", None
)
if _cache_key_traversal is None:
_cache_key_traversal = cls.__dict__.get(
"_traverse_internals", None
)
if _cache_key_traversal is None:
cls._generated_cache_key_traversal = NO_CACHE
if (
inherit_cache is None
and cls._hierarchy_supports_caching
):
util.warn(
"Class %s will not make use of SQL compilation "
"caching as it does not set the 'inherit_cache' "
"attribute to ``True``. This can have "
"significant performance implications including "
"some performance degradations in comparison to "
"prior SQLAlchemy versions. Set this attribute "
"to True if this object can make use of the cache "
"key generated by the superclass. Alternatively, "
"this attribute may be set to False which will "
"disable this warning." % (cls.__name__),
code="cprf",
)
return NO_CACHE
return _cache_key_traversal_visitor.generate_dispatch(
cls,
_cache_key_traversal,
"_generated_cache_key_traversal",
)
@util.preload_module("sqlalchemy.sql.elements")
def _gen_cache_key(
self, anon_map: anon_map, bindparams: List[BindParameter[Any]]
) -> Optional[Tuple[Any, ...]]:
"""return an optional cache key.
The cache key is a tuple which can contain any series of
objects that are hashable and also identifies
this object uniquely within the presence of a larger SQL expression
or statement, for the purposes of caching the resulting query.
The cache key should be based on the SQL compiled structure that would
ultimately be produced. That is, two structures that are composed in
exactly the same way should produce the same cache key; any difference
in the structures that would affect the SQL string or the type handlers
should result in a different cache key.
If a structure cannot produce a useful cache key, the NO_CACHE
symbol should be added to the anon_map and the method should
return None.
"""
cls = self.__class__
id_, found = anon_map.get_anon(self)
if found:
return (id_, cls)
dispatcher: Union[
Literal[CacheConst.NO_CACHE],
_CacheKeyTraversalDispatchType,
]
try:
dispatcher = cls.__dict__["_generated_cache_key_traversal"]
except KeyError:
# traversals.py -> _preconfigure_traversals()
# may be used to run these ahead of time, but
# is not enabled right now.
# this block will generate any remaining dispatchers.
dispatcher = cls._generate_cache_attrs()
if dispatcher is NO_CACHE:
anon_map[NO_CACHE] = True
return None
result: Tuple[Any, ...] = (id_, cls)
# inline of _cache_key_traversal_visitor.run_generated_dispatch()
for attrname, obj, meth in dispatcher(
self, _cache_key_traversal_visitor
):
if obj is not None:
# TODO: see if C code can help here as Python lacks an
# efficient switch construct
if meth is STATIC_CACHE_KEY:
sck = obj._static_cache_key
if sck is NO_CACHE:
anon_map[NO_CACHE] = True
return None
result += (attrname, sck)
elif meth is ANON_NAME:
elements = util.preloaded.sql_elements
if isinstance(obj, elements._anonymous_label):
obj = obj.apply_map(anon_map) # type: ignore
result += (attrname, obj)
elif meth is CALL_GEN_CACHE_KEY:
result += (
attrname,
obj._gen_cache_key(anon_map, bindparams),
)
# remaining cache functions are against
# Python tuples, dicts, lists, etc. so we can skip
# if they are empty
elif obj:
if meth is CACHE_IN_PLACE:
result += (attrname, obj)
elif meth is PROPAGATE_ATTRS:
result += (
attrname,
obj["compile_state_plugin"],
(
obj["plugin_subject"]._gen_cache_key(
anon_map, bindparams
)
if obj["plugin_subject"]
else None
),
)
elif meth is InternalTraversal.dp_annotations_key:
# obj is here is the _annotations dict. Table uses
# a memoized version of it. however in other cases,
# we generate it given anon_map as we may be from a
# Join, Aliased, etc.
# see #8790
if self._gen_static_annotations_cache_key: # type: ignore # noqa: E501
result += self._annotations_cache_key # type: ignore # noqa: E501
else:
result += self._gen_annotations_cache_key(anon_map) # type: ignore # noqa: E501
elif (
meth is InternalTraversal.dp_clauseelement_list
or meth is InternalTraversal.dp_clauseelement_tuple
or meth
is InternalTraversal.dp_memoized_select_entities
):
result += (
attrname,
tuple(
[
elem._gen_cache_key(anon_map, bindparams)
for elem in obj
]
),
)
else:
result += meth( # type: ignore
attrname, obj, self, anon_map, bindparams
)
return result
def _generate_cache_key(self) -> Optional[CacheKey]:
"""return a cache key.
The cache key is a tuple which can contain any series of
objects that are hashable and also identifies
this object uniquely within the presence of a larger SQL expression
or statement, for the purposes of caching the resulting query.
The cache key should be based on the SQL compiled structure that would
ultimately be produced. That is, two structures that are composed in
exactly the same way should produce the same cache key; any difference
in the structures that would affect the SQL string or the type handlers
should result in a different cache key.
The cache key returned by this method is an instance of
:class:`.CacheKey`, which consists of a tuple representing the
cache key, as well as a list of :class:`.BindParameter` objects
which are extracted from the expression. While two expressions
that produce identical cache key tuples will themselves generate
identical SQL strings, the list of :class:`.BindParameter` objects
indicates the bound values which may have different values in
each one; these bound parameters must be consulted in order to
execute the statement with the correct parameters.
a :class:`_expression.ClauseElement` structure that does not implement
a :meth:`._gen_cache_key` method and does not implement a
:attr:`.traverse_internals` attribute will not be cacheable; when
such an element is embedded into a larger structure, this method
will return None, indicating no cache key is available.
"""
bindparams: List[BindParameter[Any]] = []
_anon_map = anon_map()
key = self._gen_cache_key(_anon_map, bindparams)
if NO_CACHE in _anon_map:
return None
else:
assert key is not None
return CacheKey(key, bindparams)
@classmethod
def _generate_cache_key_for_object(
cls, obj: HasCacheKey
) -> Optional[CacheKey]:
bindparams: List[BindParameter[Any]] = []
_anon_map = anon_map()
key = obj._gen_cache_key(_anon_map, bindparams)
if NO_CACHE in _anon_map:
return None
else:
assert key is not None
return CacheKey(key, bindparams)
class HasCacheKeyTraverse(HasTraverseInternals, HasCacheKey):
pass
class MemoizedHasCacheKey(HasCacheKey, HasMemoized):
__slots__ = ()
@HasMemoized.memoized_instancemethod
def _generate_cache_key(self) -> Optional[CacheKey]:
return HasCacheKey._generate_cache_key(self)
class SlotsMemoizedHasCacheKey(HasCacheKey, util.MemoizedSlots):
__slots__ = ()
def _memoized_method__generate_cache_key(self) -> Optional[CacheKey]:
return HasCacheKey._generate_cache_key(self)
class CacheKey(NamedTuple):
"""The key used to identify a SQL statement construct in the
SQL compilation cache.
.. seealso::
:ref:`sql_caching`
"""
key: Tuple[Any, ...]
bindparams: Sequence[BindParameter[Any]]
# can't set __hash__ attribute because it interferes
# with namedtuple
# can't use "if not TYPE_CHECKING" because mypy rejects it
# inside of a NamedTuple
def __hash__(self) -> Optional[int]: # type: ignore
"""CacheKey itself is not hashable - hash the .key portion"""
return None
def to_offline_string(
self,
statement_cache: MutableMapping[Any, str],
statement: ClauseElement,
parameters: _CoreSingleExecuteParams,
) -> str:
"""Generate an "offline string" form of this :class:`.CacheKey`
The "offline string" is basically the string SQL for the
statement plus a repr of the bound parameter values in series.
Whereas the :class:`.CacheKey` object is dependent on in-memory
identities in order to work as a cache key, the "offline" version
is suitable for a cache that will work for other processes as well.
The given ``statement_cache`` is a dictionary-like object where the
string form of the statement itself will be cached. This dictionary
should be in a longer lived scope in order to reduce the time spent
stringifying statements.
"""
if self.key not in statement_cache:
statement_cache[self.key] = sql_str = str(statement)
else:
sql_str = statement_cache[self.key]
if not self.bindparams:
param_tuple = tuple(parameters[key] for key in sorted(parameters))
else:
param_tuple = tuple(
parameters.get(bindparam.key, bindparam.value)
for bindparam in self.bindparams
)
return repr((sql_str, param_tuple))
def __eq__(self, other: Any) -> bool:
return bool(self.key == other.key)
def __ne__(self, other: Any) -> bool:
return not (self.key == other.key)
@classmethod
def _diff_tuples(cls, left: CacheKey, right: CacheKey) -> str:
ck1 = CacheKey(left, [])
ck2 = CacheKey(right, [])
return ck1._diff(ck2)
def _whats_different(self, other: CacheKey) -> Iterator[str]:
k1 = self.key
k2 = other.key
stack: List[int] = []
pickup_index = 0
while True:
s1, s2 = k1, k2
for idx in stack:
s1 = s1[idx]
s2 = s2[idx]
for idx, (e1, e2) in enumerate(zip_longest(s1, s2)):
if idx < pickup_index:
continue
if e1 != e2:
if isinstance(e1, tuple) and isinstance(e2, tuple):
stack.append(idx)
break
else:
yield "key%s[%d]: %s != %s" % (
"".join("[%d]" % id_ for id_ in stack),
idx,
e1,
e2,
)
else:
pickup_index = stack.pop(-1)
break
def _diff(self, other: CacheKey) -> str:
return ", ".join(self._whats_different(other))
def __str__(self) -> str:
stack: List[Union[Tuple[Any, ...], HasCacheKey]] = [self.key]
output = []
sentinel = object()
indent = -1
while stack:
elem = stack.pop(0)
if elem is sentinel:
output.append((" " * (indent * 2)) + "),")
indent -= 1
elif isinstance(elem, tuple):
if not elem:
output.append((" " * ((indent + 1) * 2)) + "()")
else:
indent += 1
stack = list(elem) + [sentinel] + stack
output.append((" " * (indent * 2)) + "(")
else:
if isinstance(elem, HasCacheKey):
repr_ = "<%s object at %s>" % (
type(elem).__name__,
hex(id(elem)),
)
else:
repr_ = repr(elem)
output.append((" " * (indent * 2)) + " " + repr_ + ", ")
return "CacheKey(key=%s)" % ("\n".join(output),)
def _generate_param_dict(self) -> Dict[str, Any]:
"""used for testing"""
_anon_map = prefix_anon_map()
return {b.key % _anon_map: b.effective_value for b in self.bindparams}
@util.preload_module("sqlalchemy.sql.elements")
def _apply_params_to_element(
self, original_cache_key: CacheKey, target_element: ColumnElement[Any]
) -> ColumnElement[Any]:
if target_element._is_immutable or original_cache_key is self:
return target_element
elements = util.preloaded.sql_elements
return elements._OverrideBinds(
target_element, self.bindparams, original_cache_key.bindparams
)
def _ad_hoc_cache_key_from_args(
tokens: Tuple[Any, ...],
traverse_args: Iterable[Tuple[str, InternalTraversal]],
args: Iterable[Any],
) -> Tuple[Any, ...]:
"""a quick cache key generator used by reflection.flexi_cache."""
bindparams: List[BindParameter[Any]] = []
_anon_map = anon_map()
tup = tokens
for (attrname, sym), arg in zip(traverse_args, args):
key = sym.name
visit_key = key.replace("dp_", "visit_")
if arg is None:
tup += (attrname, None)
continue
meth = getattr(_cache_key_traversal_visitor, visit_key)
if meth is CACHE_IN_PLACE:
tup += (attrname, arg)
elif meth in (
CALL_GEN_CACHE_KEY,
STATIC_CACHE_KEY,
ANON_NAME,
PROPAGATE_ATTRS,
):
raise NotImplementedError(
f"Haven't implemented symbol {meth} for ad-hoc key from args"
)
else:
tup += meth(attrname, arg, None, _anon_map, bindparams)
return tup
class _CacheKeyTraversal(HasTraversalDispatch):
# very common elements are inlined into the main _get_cache_key() method
# to produce a dramatic savings in Python function call overhead
visit_has_cache_key = visit_clauseelement = CALL_GEN_CACHE_KEY
visit_clauseelement_list = InternalTraversal.dp_clauseelement_list
visit_annotations_key = InternalTraversal.dp_annotations_key
visit_clauseelement_tuple = InternalTraversal.dp_clauseelement_tuple
visit_memoized_select_entities = (
InternalTraversal.dp_memoized_select_entities
)
visit_string = visit_boolean = visit_operator = visit_plain_obj = (
CACHE_IN_PLACE
)
visit_statement_hint_list = CACHE_IN_PLACE
visit_type = STATIC_CACHE_KEY
visit_anon_name = ANON_NAME
visit_propagate_attrs = PROPAGATE_ATTRS
def visit_with_context_options(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return tuple((fn.__code__, c_key) for fn, c_key in obj)
def visit_inspectable(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return (attrname, inspect(obj)._gen_cache_key(anon_map, bindparams))
def visit_string_list(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return tuple(obj)
def visit_multi(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return (
attrname,
(
obj._gen_cache_key(anon_map, bindparams)
if isinstance(obj, HasCacheKey)
else obj
),
)
def visit_multi_list(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return (
attrname,
tuple(
(
elem._gen_cache_key(anon_map, bindparams)
if isinstance(elem, HasCacheKey)
else elem
)
for elem in obj
),
)
def visit_has_cache_key_tuples(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
if not obj:
return ()
return (
attrname,
tuple(
tuple(
elem._gen_cache_key(anon_map, bindparams)
for elem in tup_elem
)
for tup_elem in obj
),
)
def visit_has_cache_key_list(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
if not obj:
return ()
return (
attrname,
tuple(elem._gen_cache_key(anon_map, bindparams) for elem in obj),
)
def visit_executable_options(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
if not obj:
return ()
return (
attrname,
tuple(
elem._gen_cache_key(anon_map, bindparams)
for elem in obj
if elem._is_has_cache_key
),
)
def visit_inspectable_list(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return self.visit_has_cache_key_list(
attrname, [inspect(o) for o in obj], parent, anon_map, bindparams
)
def visit_clauseelement_tuples(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return self.visit_has_cache_key_tuples(
attrname, obj, parent, anon_map, bindparams
)
def visit_fromclause_ordered_set(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
if not obj:
return ()
return (
attrname,
tuple([elem._gen_cache_key(anon_map, bindparams) for elem in obj]),
)
def visit_clauseelement_unordered_set(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
if not obj:
return ()
cache_keys = [
elem._gen_cache_key(anon_map, bindparams) for elem in obj
]
return (
attrname,
tuple(
sorted(cache_keys)
), # cache keys all start with (id_, class)
)
def visit_named_ddl_element(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return (attrname, obj.name)
def visit_prefix_sequence(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
if not obj:
return ()
return (
attrname,
tuple(
[
(clause._gen_cache_key(anon_map, bindparams), strval)
for clause, strval in obj
]
),
)
def visit_setup_join_tuple(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return tuple(
(
target._gen_cache_key(anon_map, bindparams),
(
onclause._gen_cache_key(anon_map, bindparams)
if onclause is not None
else None
),
(
from_._gen_cache_key(anon_map, bindparams)
if from_ is not None
else None
),
tuple([(key, flags[key]) for key in sorted(flags)]),
)
for (target, onclause, from_, flags) in obj
)
def visit_table_hint_list(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
if not obj:
return ()
return (
attrname,
tuple(
[
(
clause._gen_cache_key(anon_map, bindparams),
dialect_name,
text,
)
for (clause, dialect_name), text in obj.items()
]
),
)
def visit_plain_dict(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return (attrname, tuple([(key, obj[key]) for key in sorted(obj)]))
def visit_dialect_options(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return (
attrname,
tuple(
(
dialect_name,
tuple(
[
(key, obj[dialect_name][key])
for key in sorted(obj[dialect_name])
]
),
)
for dialect_name in sorted(obj)
),
)
def visit_string_clauseelement_dict(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return (
attrname,
tuple(
(key, obj[key]._gen_cache_key(anon_map, bindparams))
for key in sorted(obj)
),
)
def visit_string_multi_dict(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return (
attrname,
tuple(
(
key,
(
value._gen_cache_key(anon_map, bindparams)
if isinstance(value, HasCacheKey)
else value
),
)
for key, value in [(key, obj[key]) for key in sorted(obj)]
),
)
def visit_fromclause_canonical_column_collection(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
# inlining into the internals of ColumnCollection
return (
attrname,
tuple(
col._gen_cache_key(anon_map, bindparams)
for k, col, _ in obj._collection
),
)
def visit_unknown_structure(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
anon_map[NO_CACHE] = True
return ()
def visit_dml_ordered_values(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
return (
attrname,
tuple(
(
(
key._gen_cache_key(anon_map, bindparams)
if hasattr(key, "__clause_element__")
else key
),
value._gen_cache_key(anon_map, bindparams),
)
for key, value in obj
),
)
def visit_dml_values(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
# in py37 we can assume two dictionaries created in the same
# insert ordering will retain that sorting
return (
attrname,
tuple(
(
(
k._gen_cache_key(anon_map, bindparams)
if hasattr(k, "__clause_element__")
else k
),
obj[k]._gen_cache_key(anon_map, bindparams),
)
for k in obj
),
)
def visit_dml_multi_values(
self,
attrname: str,
obj: Any,
parent: Any,
anon_map: anon_map,
bindparams: List[BindParameter[Any]],
) -> Tuple[Any, ...]:
# multivalues are simply not cacheable right now
anon_map[NO_CACHE] = True
return ()
_cache_key_traversal_visitor = _CacheKeyTraversal()