diff options
Diffstat (limited to 'venv/lib/python3.11/site-packages/faker/providers/barcode/en_US')
2 files changed, 249 insertions, 0 deletions
diff --git a/venv/lib/python3.11/site-packages/faker/providers/barcode/en_US/__init__.py b/venv/lib/python3.11/site-packages/faker/providers/barcode/en_US/__init__.py new file mode 100644 index 0000000..e009dfc --- /dev/null +++ b/venv/lib/python3.11/site-packages/faker/providers/barcode/en_US/__init__.py @@ -0,0 +1,249 @@ +import re + +from itertools import product +from typing import Dict, Optional, Pattern + +from .. import PrefixType +from .. import Provider as BarcodeProvider + + +class Provider(BarcodeProvider): + """Implement barcode provider for ``en_US`` locale. + + Sources: + + - https://gs1.org/standards/id-keys/company-prefix + """ + + local_prefixes = ( + *product((0,), range(10)), + *product((1,), range(4)), + ) + + upc_e_base_pattern: Pattern = re.compile(r"^\d{6}$") + upc_ae_pattern1: Pattern = re.compile( + r"^(?P<number_system_digit>[01])" # The first digit must be 0 or 1 + r"(?=\d{11}$)" # followed by 11 digits of which + r"(?P<mfr_code>\d{2})" # the first 2 digits make up the manufacturer code, + r"(?:(?P<extra>[012])0{4})" # if immediately followed by 00000, 10000, or 20000, + r"(?P<product_code>\d{3})" # a 3-digit product code, + r"(?P<check_digit>\d)$", # and finally a check digit. + ) + upc_ae_pattern2: Pattern = re.compile( + r"^(?P<number_system_digit>[01])" # The first digit must be 0 or 1 + r"(?=\d{11}$)" # followed by 11 digits of which + r"(?P<mfr_code>\d{3,4}?)" # the first 3 or 4 digits make up the manufacturer code, + r"(?:0{5})" # if immediately followed by 00000, + r"(?P<product_code>\d{1,2})" # a 2-digit or single digit product code, + r"(?P<check_digit>\d)$", # and finally a check digit. + ) + upc_ae_pattern3: Pattern = re.compile( + r"^(?P<number_system_digit>[01])" # The first digit must be 0 or 1 + r"(?=\d{11}$)" # followed by 11 digits of which + r"(?P<mfr_code>\d{5})" # the first 5 digits make up the manufacturer code, + r"(?:0{4}(?P<extra>[5-9]))" # if immediately followed by 0000 and a 5, 6, 7, 8, or 9, + r"(?P<check_digit>\d)$", # and finally a check digit. + ) + + def ean13(self, prefixes: PrefixType = (), leading_zero: Optional[bool] = None) -> str: + """Generate an EAN-13 barcode. + + If ``leading_zero`` is ``True``, the leftmost digit of the barcode will + be set to ``0``. If ``False``, the leftmost digit cannot be ``0``. If + ``None`` (default), the leftmost digit can be any digit. + + If a value for ``prefixes`` is specified, the result will begin with one + of the sequences in ``prefixes`` and will ignore ``leading_zero``. + + This method uses the standard barcode provider's |ean13| under the + hood with the ``prefixes`` argument set to the correct value to attain + the behavior described above. + + .. note:: + EAN-13 barcode that starts with a zero can be converted to UPC-A + by dropping the leading zero. This may cause problems with readers + that treat all of these code as UPC-A codes and drop the first digit + when reading it. + + You can set the argument ``prefixes`` ( or ``leading_zero`` for + convenience) explicitly to avoid or to force the generated barcode to + start with a zero. You can also generate actual UPC-A barcode with + |EnUsBarcodeProvider.upc_a|. + + :sample: + :sample: leading_zero=False + :sample: leading_zero=True + :sample: prefixes=('00',) + :sample: prefixes=('45', '49') + """ + if not prefixes: + if leading_zero is True: + prefixes = ((0,),) + elif leading_zero is False: + prefixes = ((self.random_int(1, 9),),) + + return super().ean13(prefixes=prefixes) + + def _convert_upc_a2e(self, upc_a: str) -> str: + """Convert a 12-digit UPC-A barcode to its 8-digit UPC-E equivalent. + + .. warning:: + Not all UPC-A barcodes can be converted. + """ + if not isinstance(upc_a, str): + raise TypeError("`upc_a` is not a string") + m1 = self.upc_ae_pattern1.match(upc_a) + m2 = self.upc_ae_pattern2.match(upc_a) + m3 = self.upc_ae_pattern3.match(upc_a) + if not any([m1, m2, m3]): + raise ValueError("`upc_a` has an invalid value") + upc_e_template = "{number_system_digit}{mfr_code}{product_code}{extra}{check_digit}" + if m1: + upc_e = upc_e_template.format(**m1.groupdict()) + elif m2: + groupdict: Dict[str, str] = m2.groupdict() + mfr_code = groupdict.get("mfr_code") or "" + groupdict["extra"] = str(len(mfr_code)) + upc_e = upc_e_template.format(**groupdict) + elif m3: + groupdict = m3.groupdict() + groupdict["product_code"] = "" + upc_e = upc_e_template.format(**groupdict) + return upc_e + + def _upc_ae(self, base: Optional[str] = None, number_system_digit: Optional[int] = None) -> str: + """Create a 12-digit UPC-A barcode that can be converted to UPC-E. + + The expected value of ``base`` is a 6-digit string. If any other value + is provided, this method will use a random 6-digit string instead. + + The expected value of ``number_system_digit`` is the integer ``0`` or + ``1``. If any other value is provided, this method will randomly choose + from the two. + + Please also view notes on |EnUsBarcodeProvider.upc_a| and + |EnUsBarcodeProvider.upc_e| for more details. + """ + base_ = ( + [int(x) for x in base] + if isinstance(base, str) and self.upc_e_base_pattern.match(base) + else [self.random_int(0, 9) for _ in range(6)] + ) + if number_system_digit not in [0, 1]: + number_system_digit = self.random_int(0, 1) + + if base_[-1] <= 2: + code = base_[:2] + base_[-1:] + [0] * 4 + base_[2:-1] + elif base_[-1] <= 4: + code = base_[: base_[-1]] + [0] * 5 + base_[base_[-1] : -1] + else: + code = base_[:5] + [0] * 4 + base_[-1:] + + code.insert(0, number_system_digit) + weights = [3, 1, 3, 1, 3, 1, 3, 1, 3, 1, 3] + weighted_sum = sum(x * y for x, y in zip(code, weights)) + check_digit = (10 - weighted_sum % 10) % 10 + code.append(check_digit) + return "".join(str(x) for x in code) + + def upc_a( + self, + upc_ae_mode: bool = False, + base: Optional[str] = None, + number_system_digit: Optional[int] = None, + ) -> str: + """Generate a 12-digit UPC-A barcode. + + The value of ``upc_ae_mode`` controls how barcodes will be generated. If + ``False`` (default), barcodes are not guaranteed to have a UPC-E + equivalent. In this mode, the method uses |EnUsBarcodeProvider.ean13| + under the hood, and the values of ``base`` and ``number_system_digit`` + will be ignored. + + If ``upc_ae_mode`` is ``True``, the resulting barcodes are guaranteed to + have a UPC-E equivalent, and the values of ``base`` and + ``number_system_digit`` will be used to control what is generated. + + Under this mode, ``base`` is expected to have a 6-digit string value. If + any other value is supplied, a random 6-digit string will be used + instead. As for ``number_system_digit``, the expected value is a ``0`` + or a ``1``. If any other value is provided, this method will randomly + choose from the two. + + .. important:: + When ``upc_ae_mode`` is enabled, you might encounter instances where + different values of ``base`` (e.g. ``'120003'`` and ``'120004'``) + produce the same UPC-A barcode. This is normal, and the reason lies + within the whole conversion process. To learn more about this and + what ``base`` and ``number_system_digit`` actually represent, please + refer to |EnUsBarcodeProvider.upc_e|. + + :sample: + :sample: upc_ae_mode=True, number_system_digit=0 + :sample: upc_ae_mode=True, number_system_digit=1 + :sample: upc_ae_mode=True, base='123456', number_system_digit=0 + :sample: upc_ae_mode=True, base='120003', number_system_digit=0 + :sample: upc_ae_mode=True, base='120004', number_system_digit=0 + """ + if upc_ae_mode is True: + return self._upc_ae(base=base, number_system_digit=number_system_digit) + else: + ean13 = self.ean13(leading_zero=True) + return ean13[1:] + + def upc_e( + self, + base: Optional[str] = None, + number_system_digit: Optional[int] = None, + safe_mode: bool = True, + ) -> str: + """Generate an 8-digit UPC-E barcode. + + UPC-E barcodes can be expressed in 6, 7, or 8-digit formats, but this + method uses the 8 digit format, since it is trivial to convert to the + other two formats. The first digit (starting from the left) is + controlled by ``number_system_digit``, and it can only be a ``0`` or a + ``1``. The last digit is the check digit that is inherited from the + UPC-E barcode's UPC-A equivalent. The middle six digits are collectively + referred to as the ``base`` (for a lack of a better term). + + On that note, this method uses ``base`` and ``number_system_digit`` to + first generate a UPC-A barcode for the check digit, and what happens + next depends on the value of ``safe_mode``. The argument ``safe_mode`` + exists, because there are some UPC-E values that share the same UPC-A + equivalent. For example, any UPC-E barcode of the form ``abc0000d``, + ``abc0003d``, and ``abc0004d`` share the same UPC-A value + ``abc00000000d``, but that UPC-A value will only convert to ``abc0000d`` + because of (a) how UPC-E is just a zero-suppressed version of UPC-A and + (b) the rules around the conversion. + + If ``safe_mode`` is ``True`` (default), this method performs another set + of conversions to guarantee that the UPC-E barcodes generated can be + converted to UPC-A, and that UPC-A barcode can be converted back to the + original UPC-E barcode. Using the example above, even if the bases + ``120003`` or ``120004`` are used, the resulting UPC-E barcode will + always use the base ``120000``. + + If ``safe_mode`` is ``False``, then the ``number_system_digit``, + ``base``, and the computed check digit will just be concatenated + together to produce the UPC-E barcode, and attempting to convert the + barcode to UPC-A and back again to UPC-E will exhibit the behavior + described above. + + :sample: + :sample: base='123456' + :sample: base='123456', number_system_digit=0 + :sample: base='123456', number_system_digit=1 + :sample: base='120000', number_system_digit=0 + :sample: base='120003', number_system_digit=0 + :sample: base='120004', number_system_digit=0 + :sample: base='120000', number_system_digit=0, safe_mode=False + :sample: base='120003', number_system_digit=0, safe_mode=False + :sample: base='120004', number_system_digit=0, safe_mode=False + """ + if safe_mode is not False: + upc_ae = self._upc_ae(base=base, number_system_digit=number_system_digit) + return self._convert_upc_a2e(upc_ae) + else: + upc_ae = self._upc_ae(base=base, number_system_digit=number_system_digit) + return upc_ae[0] + "".join(str(x) for x in base or "") + upc_ae[-1] diff --git a/venv/lib/python3.11/site-packages/faker/providers/barcode/en_US/__pycache__/__init__.cpython-311.pyc b/venv/lib/python3.11/site-packages/faker/providers/barcode/en_US/__pycache__/__init__.cpython-311.pyc Binary files differnew file mode 100644 index 0000000..cac104c --- /dev/null +++ b/venv/lib/python3.11/site-packages/faker/providers/barcode/en_US/__pycache__/__init__.cpython-311.pyc |