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Diffstat (limited to 'lib/sqlalchemy/engine/_py_processors.py')
-rw-r--r-- | lib/sqlalchemy/engine/_py_processors.py | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/lib/sqlalchemy/engine/_py_processors.py b/lib/sqlalchemy/engine/_py_processors.py new file mode 100644 index 000000000..db722a978 --- /dev/null +++ b/lib/sqlalchemy/engine/_py_processors.py @@ -0,0 +1,106 @@ +# sqlalchemy/processors.py +# Copyright (C) 2010-2021 the SQLAlchemy authors and contributors +# <see AUTHORS file> +# Copyright (C) 2010 Gaetan de Menten gdementen@gmail.com +# +# This module is part of SQLAlchemy and is released under +# the MIT License: https://www.opensource.org/licenses/mit-license.php + +"""defines generic type conversion functions, as used in bind and result +processors. + +They all share one common characteristic: None is passed through unchanged. + +""" + +import datetime +import re + +from .. import util + + +def str_to_datetime_processor_factory(regexp, type_): + rmatch = regexp.match + # Even on python2.6 datetime.strptime is both slower than this code + # and it does not support microseconds. + has_named_groups = bool(regexp.groupindex) + + def process(value): + if value is None: + return None + else: + try: + m = rmatch(value) + except TypeError as err: + util.raise_( + ValueError( + "Couldn't parse %s string '%r' " + "- value is not a string." % (type_.__name__, value) + ), + from_=err, + ) + if m is None: + raise ValueError( + "Couldn't parse %s string: " + "'%s'" % (type_.__name__, value) + ) + if has_named_groups: + groups = m.groupdict(0) + return type_( + **dict( + list( + zip( + iter(groups.keys()), + list(map(int, iter(groups.values()))), + ) + ) + ) + ) + else: + return type_(*list(map(int, m.groups(0)))) + + return process + + +def to_decimal_processor_factory(target_class, scale): + fstring = "%%.%df" % scale + + def process(value): + if value is None: + return None + else: + return target_class(fstring % value) + + return process + + +def to_float(value): + if value is None: + return None + else: + return float(value) + + +def to_str(value): + if value is None: + return None + else: + return str(value) + + +def int_to_boolean(value): + if value is None: + return None + else: + return bool(value) + + +DATETIME_RE = re.compile(r"(\d+)-(\d+)-(\d+) (\d+):(\d+):(\d+)(?:\.(\d+))?") +TIME_RE = re.compile(r"(\d+):(\d+):(\d+)(?:\.(\d+))?") +DATE_RE = re.compile(r"(\d+)-(\d+)-(\d+)") + +str_to_datetime = str_to_datetime_processor_factory( + DATETIME_RE, datetime.datetime +) +str_to_time = str_to_datetime_processor_factory(TIME_RE, datetime.time) +str_to_date = str_to_datetime_processor_factory(DATE_RE, datetime.date) |