import datetime
import re
import socket
from jsonschema.compat import str_types
from jsonschema.exceptions import FormatError
class FormatChecker(object):
"""
A ``format`` property checker.
JSON Schema does not mandate that the ``format`` property actually do any
validation. If validation is desired however, instances of this class can
be hooked into validators to enable format validation.
:class:`FormatChecker` objects always return ``True`` when asked about
formats that they do not know how to validate.
To check a custom format using a function that takes an instance and
returns a ``bool``, use the :meth:`FormatChecker.checks` or
:meth:`FormatChecker.cls_checks` decorators.
Arguments:
formats (iterable):
The known formats to validate. This argument can be used to
limit which formats will be used during validation.
"""
checkers = {}
def __init__(self, formats=None):
if formats is None:
self.checkers = self.checkers.copy()
else:
self.checkers = dict((k, self.checkers[k]) for k in formats)
def checks(self, format, raises=()):
"""
Register a decorated function as validating a new format.
Arguments:
format (str):
The format that the decorated function will check.
raises (Exception):
The exception(s) raised by the decorated function when
an invalid instance is found.
The exception object will be accessible as the
:attr:`ValidationError.cause` attribute of the resulting
validation error.
"""
def _checks(func):
self.checkers[format] = (func, raises)
return func
return _checks
cls_checks = classmethod(checks)
def check(self, instance, format):
"""
Check whether the instance conforms to the given format.
Arguments:
instance (any primitive type, i.e. str, number, bool):
The instance to check
format (str):
The format that instance should conform to
Raises:
:exc:`FormatError` if instance does not conform to ``format``
"""
if format not in self.checkers:
return
func, raises = self.checkers[format]
result, cause = None, None
try:
result = func(instance)
except raises as e:
cause = e
if not result:
raise FormatError(
"%r is not a %r" % (instance, format), cause=cause,
)
def conforms(self, instance, format):
"""
Check whether the instance conforms to the given format.
Arguments:
instance (any primitive type, i.e. str, number, bool):
The instance to check
format (str):
The format that instance should conform to
Returns:
bool: Whether it conformed
"""
try:
self.check(instance, format)
except FormatError:
return False
else:
return True
_draft_checkers = {"draft3": [], "draft4": []}
def _checks_drafts(both=None, draft3=None, draft4=None, raises=()):
draft3 = draft3 or both
draft4 = draft4 or both
def wrap(func):
if draft3:
_draft_checkers["draft3"].append(draft3)
func = FormatChecker.cls_checks(draft3, raises)(func)
if draft4:
_draft_checkers["draft4"].append(draft4)
func = FormatChecker.cls_checks(draft4, raises)(func)
return func
return wrap
@_checks_drafts("email")
def is_email(instance):
if not isinstance(instance, str_types):
return True
return "@" in instance
_ipv4_re = re.compile(r"^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$")
@_checks_drafts(draft3="ip-address", draft4="ipv4")
def is_ipv4(instance):
if not isinstance(instance, str_types):
return True
if not _ipv4_re.match(instance):
return False
return all(0 <= int(component) <= 255 for component in instance.split("."))
if hasattr(socket, "inet_pton"):
@_checks_drafts("ipv6", raises=socket.error)
def is_ipv6(instance):
if not isinstance(instance, str_types):
return True
return socket.inet_pton(socket.AF_INET6, instance)
_host_name_re = re.compile(r"^[A-Za-z0-9][A-Za-z0-9\.\-]{1,255}$")
@_checks_drafts(draft3="host-name", draft4="hostname")
def is_host_name(instance):
if not isinstance(instance, str_types):
return True
if not _host_name_re.match(instance):
return False
components = instance.split(".")
for component in components:
if len(component) > 63:
return False
return True
try:
import rfc3987
except ImportError:
pass
else:
@_checks_drafts("uri", raises=ValueError)
def is_uri(instance):
if not isinstance(instance, str_types):
return True
return rfc3987.parse(instance, rule="URI")
try:
import strict_rfc3339
except ImportError:
try:
import isodate
except ImportError:
pass
else:
@_checks_drafts("date-time", raises=(ValueError, isodate.ISO8601Error))
def is_datetime(instance):
if not isinstance(instance, str_types):
return True
return isodate.parse_datetime(instance)
else:
@_checks_drafts("date-time")
def is_datetime(instance):
if not isinstance(instance, str_types):
return True
return strict_rfc3339.validate_rfc3339(instance)
@_checks_drafts("regex", raises=re.error)
def is_regex(instance):
if not isinstance(instance, str_types):
return True
return re.compile(instance)
@_checks_drafts(draft3="date", raises=ValueError)
def is_date(instance):
if not isinstance(instance, str_types):
return True
return datetime.datetime.strptime(instance, "%Y-%m-%d")
@_checks_drafts(draft3="time", raises=ValueError)
def is_time(instance):
if not isinstance(instance, str_types):
return True
return datetime.datetime.strptime(instance, "%H:%M:%S")
try:
import webcolors
except ImportError:
pass
else:
def is_css_color_code(instance):
return webcolors.normalize_hex(instance)
@_checks_drafts(draft3="color", raises=(ValueError, TypeError))
def is_css21_color(instance):
if (
not isinstance(instance, str_types) or
instance.lower() in webcolors.css21_names_to_hex
):
return True
return is_css_color_code(instance)
def is_css3_color(instance):
if instance.lower() in webcolors.css3_names_to_hex:
return True
return is_css_color_code(instance)
draft3_format_checker = FormatChecker(_draft_checkers["draft3"])
draft4_format_checker = FormatChecker(_draft_checkers["draft4"])