#!/usr/bin/env python
import logging
import datetime
from typing import Union, Optional, Any, List, TYPE_CHECKING
from collections.abc import Iterable, MutableMapping
from collections import defaultdict
from hashlib import sha1, sha256
from pathlib import Path
from enum import Enum
from deepdiff.helper import (strings, numbers, times, unprocessed, not_hashed, add_to_frozen_set,
convert_item_or_items_into_set_else_none, get_doc, ipranges,
convert_item_or_items_into_compiled_regexes_else_none,
get_id, type_is_subclass_of_type_group, type_in_type_group,
number_to_string, datetime_normalize, KEY_TO_VAL_STR,
get_truncate_datetime, dict_, add_root_to_paths, PydanticBaseModel)
from deepdiff.base import Base
if TYPE_CHECKING:
from pytz.tzinfo import BaseTzInfo
try:
import pandas
except ImportError:
pandas = False
try:
import polars
except ImportError:
polars = False
try:
import numpy as np
booleanTypes = (bool, np.bool_)
except ImportError:
booleanTypes = bool
logger = logging.getLogger(__name__)
UNPROCESSED_KEY = object()
EMPTY_FROZENSET = frozenset()
INDEX_VS_ATTRIBUTE = ('[%s]', '.%s')
HASH_LOOKUP_ERR_MSG = '{} is not one of the hashed items.'
def sha256hex(obj):
"""Use Sha256 as a cryptographic hash."""
if isinstance(obj, str):
obj = obj.encode('utf-8')
return sha256(obj).hexdigest()
def sha1hex(obj):
"""Use Sha1 as a cryptographic hash."""
if isinstance(obj, str):
obj = obj.encode('utf-8')
return sha1(obj).hexdigest()
default_hasher = sha256hex
def combine_hashes_lists(items, prefix):
"""
Combines lists of hashes into one hash
This can be optimized in future.
It needs to work with both murmur3 hashes (int) and sha256 (str)
Although murmur3 is not used anymore.
"""
if isinstance(prefix, bytes):
prefix = prefix.decode('utf-8')
hashes_bytes = b''
for item in items:
# In order to make sure the order of hashes in each item does not affect the hash
# we resort them.
hashes_bytes += (''.join(map(str, sorted(item))) + '--').encode('utf-8')
return prefix + str(default_hasher(hashes_bytes))
class BoolObj(Enum):
TRUE = 1
FALSE = 0
def prepare_string_for_hashing(
obj,
ignore_string_type_changes=False,
ignore_string_case=False,
encodings=None,
ignore_encoding_errors=False,
):
"""
Clean type conversions
"""
original_type = obj.__class__.__name__
# https://docs.python.org/3/library/codecs.html#codecs.decode
errors_mode = 'ignore' if ignore_encoding_errors else 'strict'
if isinstance(obj, bytes):
err = None
encodings = ['utf-8'] if encodings is None else encodings
encoded = False
for encoding in encodings:
try:
obj = obj.decode(encoding, errors=errors_mode)
encoded = True
break
except UnicodeDecodeError as er:
err = er
if not encoded and err is not None:
obj_decoded = obj.decode('utf-8', errors='ignore') # type: ignore
start = max(err.start - 20, 0)
start_prefix = ''
if start > 0:
start_prefix = '...'
end = err.end + 20
end_suffix = '...'
if end >= len(obj):
end = len(obj)
end_suffix = ''
raise UnicodeDecodeError(
err.encoding,
err.object,
err.start,
err.end,
f"{err.reason} in '{start_prefix}{obj_decoded[start:end]}{end_suffix}'. Please either pass ignore_encoding_errors=True or pass the encoding via encodings=['utf-8', '...']."
) from None
if not ignore_string_type_changes:
obj = KEY_TO_VAL_STR.format(original_type, obj)
if ignore_string_case:
obj = obj.lower()
return obj
doc = get_doc('deephash_doc.rst')
class DeepHash(Base):
__doc__ = doc
def __init__(self,
obj: Any,
*,
apply_hash=True,
custom_operators: Optional[List[Any]] =None,
default_timezone:Union[datetime.timezone, "BaseTzInfo"]=datetime.timezone.utc,
encodings=None,
exclude_obj_callback=None,
exclude_paths=None,
exclude_regex_paths=None,
exclude_types=None,
hasher=None,
hashes=None,
ignore_encoding_errors=False,
ignore_iterable_order=True,
ignore_numeric_type_changes=False,
ignore_private_variables=True,
ignore_repetition=True,
ignore_string_case=False,
ignore_string_type_changes=False,
ignore_type_in_groups=None,
ignore_type_subclasses=False,
include_paths=None,
number_format_notation="f",
number_to_string_func=None,
parent="root",
significant_digits=None,
truncate_datetime=None,
use_enum_value=False,
**kwargs):
if kwargs:
raise ValueError(
("The following parameter(s) are not valid: %s\n"
"The valid parameters are obj, hashes, exclude_types, significant_digits, truncate_datetime,"
"exclude_paths, include_paths, exclude_regex_paths, hasher, ignore_repetition, "
"number_format_notation, apply_hash, ignore_type_in_groups, ignore_string_type_changes, "
"ignore_numeric_type_changes, ignore_type_subclasses, ignore_string_case "
"number_to_string_func, ignore_private_variables, parent, use_enum_value, default_timezone "
"encodings, ignore_encoding_errors") % ', '.join(kwargs.keys()))
if isinstance(hashes, MutableMapping):
self.hashes = hashes
elif isinstance(hashes, DeepHash):
self.hashes = hashes.hashes
else:
self.hashes = dict_()
exclude_types = set() if exclude_types is None else set(exclude_types)
self.exclude_types_tuple = tuple(exclude_types) # we need tuple for checking isinstance
self.ignore_repetition = ignore_repetition
self.exclude_paths = add_root_to_paths(convert_item_or_items_into_set_else_none(exclude_paths))
self.include_paths = add_root_to_paths(convert_item_or_items_into_set_else_none(include_paths))
self.exclude_regex_paths = convert_item_or_items_into_compiled_regexes_else_none(exclude_regex_paths)
self.hasher = default_hasher if hasher is None else hasher
self.hashes[UNPROCESSED_KEY] = []
self.use_enum_value = use_enum_value
self.default_timezone = default_timezone
self.significant_digits = self.get_significant_digits(significant_digits, ignore_numeric_type_changes)
self.truncate_datetime = get_truncate_datetime(truncate_datetime)
self.number_format_notation = number_format_notation
self.ignore_type_in_groups = self.get_ignore_types_in_groups(
ignore_type_in_groups=ignore_type_in_groups,
ignore_string_type_changes=ignore_string_type_changes,
ignore_numeric_type_changes=ignore_numeric_type_changes,
ignore_type_subclasses=ignore_type_subclasses)
self.ignore_string_type_changes = ignore_string_type_changes
self.ignore_numeric_type_changes = ignore_numeric_type_changes
self.ignore_string_case = ignore_string_case
self.exclude_obj_callback = exclude_obj_callback
# makes the hash return constant size result if true
# the only time it should be set to False is when
# testing the individual hash functions for different types of objects.
self.apply_hash = apply_hash
self.type_check_func = type_in_type_group if ignore_type_subclasses else type_is_subclass_of_type_group
# self.type_check_func = type_is_subclass_of_type_group if ignore_type_subclasses else type_in_type_group
self.number_to_string = number_to_string_func or number_to_string
self.ignore_private_variables = ignore_private_variables
self.encodings = encodings
self.ignore_encoding_errors = ignore_encoding_errors
self.ignore_iterable_order = ignore_iterable_order
self.custom_operators = custom_operators
self._hash(obj, parent=parent, parents_ids=frozenset({get_id(obj)}))
if self.hashes[UNPROCESSED_KEY]:
logger.warning("Can not hash the following items: {}.".format(self.hashes[UNPROCESSED_KEY]))
else:
del self.hashes[UNPROCESSED_KEY]
sha256hex = sha256hex
sha1hex = sha1hex
def __getitem__(self, obj, extract_index=0):
return self._getitem(self.hashes, obj, extract_index=extract_index, use_enum_value=self.use_enum_value)
@staticmethod
def _getitem(hashes, obj, extract_index=0, use_enum_value=False):
"""
extract_index is zero for hash and 1 for count and None to get them both.
To keep it backward compatible, we only get the hash by default so it is set to zero by default.
"""
key = obj
if obj is True:
key = BoolObj.TRUE
elif obj is False:
key = BoolObj.FALSE
elif use_enum_value and isinstance(obj, Enum):
key = obj.value
result_n_count = (None, 0)
try:
result_n_count = hashes[key]
except (TypeError, KeyError):
key = get_id(obj)
try:
result_n_count = hashes[key]
except KeyError:
raise KeyError(HASH_LOOKUP_ERR_MSG.format(obj)) from None
if obj is UNPROCESSED_KEY:
extract_index = None
return result_n_count if extract_index is None else result_n_count[extract_index]
def __contains__(self, obj):
result = False
try:
result = obj in self.hashes
except (TypeError, KeyError):
result = False
if not result:
result = get_id(obj) in self.hashes
return result
def get(self, key, default=None, extract_index=0):
"""
Get method for the hashes dictionary.
It can extract the hash for a given key that is already calculated when extract_index=0
or the count of items that went to building the object whenextract_index=1.
"""
return self.get_key(self.hashes, key, default=default, extract_index=extract_index)
@staticmethod
def get_key(hashes, key, default=None, extract_index=0, use_enum_value=False):
"""
get_key method for the hashes dictionary.
It can extract the hash for a given key that is already calculated when extract_index=0
or the count of items that went to building the object whenextract_index=1.
"""
try:
result = DeepHash._getitem(hashes, key, extract_index=extract_index, use_enum_value=use_enum_value)
except KeyError:
result = default
return result
def _get_objects_to_hashes_dict(self, extract_index=0):
"""
A dictionary containing only the objects to hashes,
or a dictionary of objects to the count of items that went to build them.
extract_index=0 for hashes and extract_index=1 for counts.
"""
result = dict_()
for key, value in self.hashes.items():
if key is UNPROCESSED_KEY:
result[key] = value
else:
result[key] = value[extract_index]
return result
def __eq__(self, other):
if isinstance(other, DeepHash):
return self.hashes == other.hashes
else:
# We only care about the hashes
return self._get_objects_to_hashes_dict() == other
__req__ = __eq__
def __repr__(self):
"""
Hide the counts since it will be confusing to see them when they are hidden everywhere else.
"""
from deepdiff.summarize import summarize
return summarize(self._get_objects_to_hashes_dict(extract_index=0), max_length=500)
def __str__(self):
return str(self._get_objects_to_hashes_dict(extract_index=0))
def __bool__(self):
return bool(self.hashes)
def keys(self):
return self.hashes.keys()
def values(self):
return (i[0] for i in self.hashes.values()) # Just grab the item and not its count
def items(self):
return ((i, v[0]) for i, v in self.hashes.items())
def _prep_obj(self, obj, parent, parents_ids=EMPTY_FROZENSET, is_namedtuple=False, is_pydantic_object=False):
"""prepping objects"""
original_type = type(obj) if not isinstance(obj, type) else obj
obj_to_dict_strategies = []
if is_namedtuple:
obj_to_dict_strategies.append(lambda o: o._asdict())
elif is_pydantic_object:
obj_to_dict_strategies.append(lambda o: {k: v for (k, v) in o.__dict__.items() if v !="model_fields_set"})
else:
obj_to_dict_strategies.append(lambda o: o.__dict__)
if hasattr(obj, "__slots__"):
obj_to_dict_strategies.append(lambda o: {i: getattr(o, i) for i in o.__slots__})
else:
import inspect
obj_to_dict_strategies.append(lambda o: dict(inspect.getmembers(o, lambda m: not inspect.isroutine(m))))
for get_dict in obj_to_dict_strategies:
try:
d = get_dict(obj)
break
except AttributeError:
pass
else:
self.hashes[UNPROCESSED_KEY].append(obj)
return (unprocessed, 0)
obj = d
result, counts = self._prep_dict(obj, parent=parent, parents_ids=parents_ids,
print_as_attribute=True, original_type=original_type)
result = "nt{}".format(result) if is_namedtuple else "obj{}".format(result)
return result, counts
def _skip_this(self, obj, parent):
skip = False
if self.exclude_paths and parent in self.exclude_paths:
skip = True
if self.include_paths and parent != 'root':
if parent not in self.include_paths:
skip = True
for prefix in self.include_paths:
if parent.startswith(prefix):
skip = False
break
elif self.exclude_regex_paths and any(
[exclude_regex_path.search(parent) for exclude_regex_path in self.exclude_regex_paths]): # type: ignore
skip = True
elif self.exclude_types_tuple and isinstance(obj, self.exclude_types_tuple):
skip = True
elif self.exclude_obj_callback and self.exclude_obj_callback(obj, parent):
skip = True
return skip
def _prep_dict(self, obj, parent, parents_ids=EMPTY_FROZENSET, print_as_attribute=False, original_type=None):
result = []
counts = 1
key_text = "%s{}".format(INDEX_VS_ATTRIBUTE[print_as_attribute])
for key, item in obj.items():
counts += 1
# ignore private variables
if self.ignore_private_variables and isinstance(key, str) and key.startswith('__'):
continue
key_formatted = "'%s'" % key if not print_as_attribute and isinstance(key, strings) else key
key_in_report = key_text % (parent, key_formatted)
key_hash, _ = self._hash(key, parent=key_in_report, parents_ids=parents_ids)
if not key_hash:
continue
item_id = get_id(item)
if (parents_ids and item_id in parents_ids) or self._skip_this(item, parent=key_in_report):
continue
parents_ids_added = add_to_frozen_set(parents_ids, item_id)
hashed, count = self._hash(item, parent=key_in_report, parents_ids=parents_ids_added)
hashed = KEY_TO_VAL_STR.format(key_hash, hashed)
result.append(hashed)
counts += count
result.sort()
result = ';'.join(result)
if print_as_attribute:
type_ = original_type or type(obj)
type_str = type_.__name__
for type_group in self.ignore_type_in_groups:
if self.type_check_func(type_, type_group):
type_str = ','.join(map(lambda x: x.__name__, type_group))
break
else:
type_str = 'dict'
return "{}:{{{}}}".format(type_str, result), counts
def _prep_iterable(self, obj, parent, parents_ids=EMPTY_FROZENSET):
counts = 1
result = defaultdict(int)
for i, item in enumerate(obj):
new_parent = "{}[{}]".format(parent, i)
if self._skip_this(item, parent=new_parent):
continue
item_id = get_id(item)
if parents_ids and item_id in parents_ids:
continue
parents_ids_added = add_to_frozen_set(parents_ids, item_id)
hashed, count = self._hash(item, parent=new_parent, parents_ids=parents_ids_added)
# counting repetitions
result[hashed] += 1
counts += count
if self.ignore_repetition:
result = list(result.keys())
else:
result = [
'{}|{}'.format(i, v) for i, v in result.items()
]
result = map(str, result) # making sure the result items are string so join command works.
if self.ignore_iterable_order:
result = sorted(result)
result = ','.join(result)
result = KEY_TO_VAL_STR.format(type(obj).__name__, result)
return result, counts
def _prep_bool(self, obj):
return BoolObj.TRUE if obj else BoolObj.FALSE
def _prep_path(self, obj):
type_ = obj.__class__.__name__
return KEY_TO_VAL_STR.format(type_, obj)
def _prep_number(self, obj):
type_ = "number" if self.ignore_numeric_type_changes else obj.__class__.__name__
if self.significant_digits is not None:
obj = self.number_to_string(obj, significant_digits=self.significant_digits,
number_format_notation=self.number_format_notation)
return KEY_TO_VAL_STR.format(type_, obj)
def _prep_ipranges(self, obj):
type_ = 'iprange'
obj = str(obj)
return KEY_TO_VAL_STR.format(type_, obj)
def _prep_datetime(self, obj):
type_ = 'datetime'
obj = datetime_normalize(self.truncate_datetime, obj, default_timezone=self.default_timezone)
return KEY_TO_VAL_STR.format(type_, obj)
def _prep_date(self, obj):
type_ = 'datetime' # yes still datetime but it doesn't need normalization
return KEY_TO_VAL_STR.format(type_, obj)
def _prep_tuple(self, obj, parent, parents_ids):
# Checking to see if it has _fields. Which probably means it is a named
# tuple.
try:
obj._asdict
# It must be a normal tuple
except AttributeError:
result, counts = self._prep_iterable(obj=obj, parent=parent, parents_ids=parents_ids)
# We assume it is a namedtuple then
else:
result, counts = self._prep_obj(obj, parent, parents_ids=parents_ids, is_namedtuple=True)
return result, counts
def _hash(self, obj, parent, parents_ids=EMPTY_FROZENSET):
"""The main hash method"""
counts = 1
if self.custom_operators is not None:
for operator in self.custom_operators:
func = getattr(operator, 'normalize_value_for_hashing', None)
if func is None:
raise NotImplementedError(f"{operator.__class__.__name__} needs to define a normalize_value_for_hashing method to be compatible with ignore_order=True or iterable_compare_func.".format(operator))
else:
obj = func(parent, obj)
if isinstance(obj, booleanTypes):
obj = self._prep_bool(obj)
result = None
elif self.use_enum_value and isinstance(obj, Enum):
obj = obj.value
else:
result = not_hashed
try:
result, counts = self.hashes[obj]
except (TypeError, KeyError):
pass
else:
return result, counts
if self._skip_this(obj, parent):
return None, 0
elif obj is None:
result = 'NONE'
elif isinstance(obj, strings):
result = prepare_string_for_hashing(
obj,
ignore_string_type_changes=self.ignore_string_type_changes,
ignore_string_case=self.ignore_string_case,
encodings=self.encodings,
ignore_encoding_errors=self.ignore_encoding_errors,
)
elif isinstance(obj, Path):
result = self._prep_path(obj)
elif isinstance(obj, times):
result = self._prep_datetime(obj)
elif isinstance(obj, datetime.date):
result = self._prep_date(obj)
elif isinstance(obj, numbers): # type: ignore
result = self._prep_number(obj)
elif isinstance(obj, ipranges):
result = self._prep_ipranges(obj)
elif isinstance(obj, MutableMapping):
result, counts = self._prep_dict(obj=obj, parent=parent, parents_ids=parents_ids)
elif isinstance(obj, tuple):
result, counts = self._prep_tuple(obj=obj, parent=parent, parents_ids=parents_ids)
elif (pandas and isinstance(obj, pandas.DataFrame)): # type: ignore
def gen(): # type: ignore
yield ('dtype', obj.dtypes) # type: ignore
yield ('index', obj.index) # type: ignore
yield from obj.items() # type: ignore # which contains (column name, series tuples)
result, counts = self._prep_iterable(obj=gen(), parent=parent, parents_ids=parents_ids)
elif (polars and isinstance(obj, polars.DataFrame)): # type: ignore
def gen():
yield from obj.columns # type: ignore
yield from list(obj.schema.items()) # type: ignore
yield from obj.rows() # type: ignore
result, counts = self._prep_iterable(obj=gen(), parent=parent, parents_ids=parents_ids)
elif isinstance(obj, Iterable):
result, counts = self._prep_iterable(obj=obj, parent=parent, parents_ids=parents_ids)
elif obj == BoolObj.TRUE or obj == BoolObj.FALSE:
result = 'bool:true' if obj is BoolObj.TRUE else 'bool:false'
elif isinstance(obj, PydanticBaseModel):
result, counts = self._prep_obj(obj=obj, parent=parent, parents_ids=parents_ids, is_pydantic_object=True)
else:
result, counts = self._prep_obj(obj=obj, parent=parent, parents_ids=parents_ids)
if result is not_hashed: # pragma: no cover
self.hashes[UNPROCESSED_KEY].append(obj)
elif result is unprocessed:
pass
elif self.apply_hash:
if isinstance(obj, strings):
result_cleaned = result
else:
result_cleaned = prepare_string_for_hashing(
result, ignore_string_type_changes=self.ignore_string_type_changes,
ignore_string_case=self.ignore_string_case)
result = self.hasher(result_cleaned)
# It is important to keep the hash of all objects.
# The hashes will be later used for comparing the objects.
# Object to hash when possible otherwise ObjectID to hash
try:
self.hashes[obj] = (result, counts)
except TypeError:
obj_id = get_id(obj)
self.hashes[obj_id] = (result, counts)
return result, counts
if __name__ == "__main__": # pragma: no cover
import doctest
doctest.testmod()