970 lines
29 KiB
Python
970 lines
29 KiB
Python
"""
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Creation and extension of validators, with implementations for existing drafts.
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"""
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from __future__ import division
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from warnings import warn
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import contextlib
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import json
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import numbers
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from six import add_metaclass
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from jsonschema import (
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_legacy_validators,
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_types,
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_utils,
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_validators,
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exceptions,
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)
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from jsonschema.compat import (
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Sequence,
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int_types,
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iteritems,
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lru_cache,
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str_types,
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unquote,
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urldefrag,
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urljoin,
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urlopen,
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urlsplit,
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)
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# Sigh. https://gitlab.com/pycqa/flake8/issues/280
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# https://github.com/pyga/ebb-lint/issues/7
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# Imported for backwards compatibility.
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from jsonschema.exceptions import ErrorTree
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ErrorTree
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class _DontDoThat(Exception):
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"""
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Raised when a Validators with non-default type checker is misused.
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Asking one for DEFAULT_TYPES doesn't make sense, since type checkers
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exist for the unrepresentable cases where DEFAULT_TYPES can't
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represent the type relationship.
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"""
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def __str__(self):
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return "DEFAULT_TYPES cannot be used on Validators using TypeCheckers"
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validators = {}
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meta_schemas = _utils.URIDict()
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def _generate_legacy_type_checks(types=()):
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"""
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Generate newer-style type checks out of JSON-type-name-to-type mappings.
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Arguments:
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types (dict):
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A mapping of type names to their Python types
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Returns:
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A dictionary of definitions to pass to `TypeChecker`
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"""
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types = dict(types)
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def gen_type_check(pytypes):
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pytypes = _utils.flatten(pytypes)
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def type_check(checker, instance):
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if isinstance(instance, bool):
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if bool not in pytypes:
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return False
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return isinstance(instance, pytypes)
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return type_check
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definitions = {}
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for typename, pytypes in iteritems(types):
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definitions[typename] = gen_type_check(pytypes)
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return definitions
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_DEPRECATED_DEFAULT_TYPES = {
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u"array": list,
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u"boolean": bool,
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u"integer": int_types,
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u"null": type(None),
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u"number": numbers.Number,
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u"object": dict,
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u"string": str_types,
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}
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_TYPE_CHECKER_FOR_DEPRECATED_DEFAULT_TYPES = _types.TypeChecker(
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type_checkers=_generate_legacy_type_checks(_DEPRECATED_DEFAULT_TYPES),
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)
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def validates(version):
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"""
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Register the decorated validator for a ``version`` of the specification.
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Registered validators and their meta schemas will be considered when
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parsing ``$schema`` properties' URIs.
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Arguments:
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version (str):
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An identifier to use as the version's name
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Returns:
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collections.Callable:
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a class decorator to decorate the validator with the version
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"""
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def _validates(cls):
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validators[version] = cls
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meta_schema_id = cls.ID_OF(cls.META_SCHEMA)
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if meta_schema_id:
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meta_schemas[meta_schema_id] = cls
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return cls
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return _validates
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def _DEFAULT_TYPES(self):
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if self._CREATED_WITH_DEFAULT_TYPES is None:
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raise _DontDoThat()
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warn(
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(
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"The DEFAULT_TYPES attribute is deprecated. "
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"See the type checker attached to this validator instead."
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),
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DeprecationWarning,
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stacklevel=2,
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)
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return self._DEFAULT_TYPES
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class _DefaultTypesDeprecatingMetaClass(type):
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DEFAULT_TYPES = property(_DEFAULT_TYPES)
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def _id_of(schema):
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if schema is True or schema is False:
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return u""
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return schema.get(u"$id", u"")
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def create(
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meta_schema,
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validators=(),
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version=None,
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default_types=None,
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type_checker=None,
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id_of=_id_of,
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):
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"""
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Create a new validator class.
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Arguments:
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meta_schema (collections.Mapping):
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the meta schema for the new validator class
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validators (collections.Mapping):
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a mapping from names to callables, where each callable will
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validate the schema property with the given name.
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Each callable should take 4 arguments:
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1. a validator instance,
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2. the value of the property being validated within the
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instance
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3. the instance
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4. the schema
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version (str):
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an identifier for the version that this validator class will
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validate. If provided, the returned validator class will
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have its ``__name__`` set to include the version, and also
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will have `jsonschema.validators.validates` automatically
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called for the given version.
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type_checker (jsonschema.TypeChecker):
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a type checker, used when applying the :validator:`type` validator.
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If unprovided, a `jsonschema.TypeChecker` will be created
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with a set of default types typical of JSON Schema drafts.
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default_types (collections.Mapping):
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.. deprecated:: 3.0.0
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Please use the type_checker argument instead.
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If set, it provides mappings of JSON types to Python types
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that will be converted to functions and redefined in this
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object's `jsonschema.TypeChecker`.
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id_of (collections.Callable):
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A function that given a schema, returns its ID.
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Returns:
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a new `jsonschema.IValidator` class
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"""
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if default_types is not None:
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if type_checker is not None:
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raise TypeError(
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"Do not specify default_types when providing a type checker.",
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)
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_created_with_default_types = True
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warn(
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(
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"The default_types argument is deprecated. "
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"Use the type_checker argument instead."
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),
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DeprecationWarning,
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stacklevel=2,
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)
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type_checker = _types.TypeChecker(
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type_checkers=_generate_legacy_type_checks(default_types),
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)
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else:
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default_types = _DEPRECATED_DEFAULT_TYPES
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if type_checker is None:
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_created_with_default_types = False
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type_checker = _TYPE_CHECKER_FOR_DEPRECATED_DEFAULT_TYPES
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elif type_checker is _TYPE_CHECKER_FOR_DEPRECATED_DEFAULT_TYPES:
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_created_with_default_types = False
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else:
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_created_with_default_types = None
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@add_metaclass(_DefaultTypesDeprecatingMetaClass)
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class Validator(object):
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VALIDATORS = dict(validators)
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META_SCHEMA = dict(meta_schema)
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TYPE_CHECKER = type_checker
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ID_OF = staticmethod(id_of)
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DEFAULT_TYPES = property(_DEFAULT_TYPES)
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_DEFAULT_TYPES = dict(default_types)
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_CREATED_WITH_DEFAULT_TYPES = _created_with_default_types
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def __init__(
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self,
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schema,
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types=(),
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resolver=None,
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format_checker=None,
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):
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if types:
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warn(
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(
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"The types argument is deprecated. Provide "
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"a type_checker to jsonschema.validators.extend "
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"instead."
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),
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DeprecationWarning,
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stacklevel=2,
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)
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self.TYPE_CHECKER = self.TYPE_CHECKER.redefine_many(
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_generate_legacy_type_checks(types),
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)
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if resolver is None:
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resolver = RefResolver.from_schema(schema, id_of=id_of)
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self.resolver = resolver
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self.format_checker = format_checker
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self.schema = schema
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@classmethod
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def check_schema(cls, schema):
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for error in cls(cls.META_SCHEMA).iter_errors(schema):
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raise exceptions.SchemaError.create_from(error)
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def iter_errors(self, instance, _schema=None):
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if _schema is None:
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_schema = self.schema
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if _schema is True:
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return
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elif _schema is False:
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yield exceptions.ValidationError(
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"False schema does not allow %r" % (instance,),
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validator=None,
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validator_value=None,
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instance=instance,
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schema=_schema,
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)
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return
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scope = id_of(_schema)
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if scope:
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self.resolver.push_scope(scope)
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try:
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ref = _schema.get(u"$ref")
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if ref is not None:
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validators = [(u"$ref", ref)]
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else:
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validators = iteritems(_schema)
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for k, v in validators:
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validator = self.VALIDATORS.get(k)
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if validator is None:
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continue
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errors = validator(self, v, instance, _schema) or ()
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for error in errors:
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# set details if not already set by the called fn
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error._set(
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validator=k,
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validator_value=v,
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instance=instance,
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schema=_schema,
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)
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if k != u"$ref":
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error.schema_path.appendleft(k)
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yield error
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finally:
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if scope:
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self.resolver.pop_scope()
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def descend(self, instance, schema, path=None, schema_path=None):
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for error in self.iter_errors(instance, schema):
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if path is not None:
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error.path.appendleft(path)
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if schema_path is not None:
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error.schema_path.appendleft(schema_path)
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yield error
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def validate(self, *args, **kwargs):
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for error in self.iter_errors(*args, **kwargs):
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raise error
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def is_type(self, instance, type):
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try:
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return self.TYPE_CHECKER.is_type(instance, type)
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except exceptions.UndefinedTypeCheck:
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raise exceptions.UnknownType(type, instance, self.schema)
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def is_valid(self, instance, _schema=None):
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error = next(self.iter_errors(instance, _schema), None)
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return error is None
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if version is not None:
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Validator = validates(version)(Validator)
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Validator.__name__ = version.title().replace(" ", "") + "Validator"
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return Validator
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def extend(validator, validators=(), version=None, type_checker=None):
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"""
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Create a new validator class by extending an existing one.
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Arguments:
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validator (jsonschema.IValidator):
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an existing validator class
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validators (collections.Mapping):
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a mapping of new validator callables to extend with, whose
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structure is as in `create`.
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.. note::
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Any validator callables with the same name as an
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existing one will (silently) replace the old validator
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callable entirely, effectively overriding any validation
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done in the "parent" validator class.
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If you wish to instead extend the behavior of a parent's
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validator callable, delegate and call it directly in
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the new validator function by retrieving it using
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``OldValidator.VALIDATORS["validator_name"]``.
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version (str):
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a version for the new validator class
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type_checker (jsonschema.TypeChecker):
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a type checker, used when applying the :validator:`type` validator.
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If unprovided, the type checker of the extended
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`jsonschema.IValidator` will be carried along.`
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Returns:
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a new `jsonschema.IValidator` class extending the one provided
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.. note:: Meta Schemas
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The new validator class will have its parent's meta schema.
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If you wish to change or extend the meta schema in the new
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validator class, modify ``META_SCHEMA`` directly on the returned
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class. Note that no implicit copying is done, so a copy should
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likely be made before modifying it, in order to not affect the
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old validator.
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"""
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all_validators = dict(validator.VALIDATORS)
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all_validators.update(validators)
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if type_checker is None:
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type_checker = validator.TYPE_CHECKER
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elif validator._CREATED_WITH_DEFAULT_TYPES:
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raise TypeError(
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"Cannot extend a validator created with default_types "
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"with a type_checker. Update the validator to use a "
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"type_checker when created."
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)
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return create(
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meta_schema=validator.META_SCHEMA,
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validators=all_validators,
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version=version,
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type_checker=type_checker,
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id_of=validator.ID_OF,
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)
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Draft3Validator = create(
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meta_schema=_utils.load_schema("draft3"),
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validators={
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u"$ref": _validators.ref,
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u"additionalItems": _validators.additionalItems,
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u"additionalProperties": _validators.additionalProperties,
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u"dependencies": _legacy_validators.dependencies_draft3,
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u"disallow": _legacy_validators.disallow_draft3,
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u"divisibleBy": _validators.multipleOf,
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u"enum": _validators.enum,
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u"extends": _legacy_validators.extends_draft3,
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u"format": _validators.format,
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u"items": _legacy_validators.items_draft3_draft4,
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u"maxItems": _validators.maxItems,
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u"maxLength": _validators.maxLength,
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u"maximum": _legacy_validators.maximum_draft3_draft4,
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u"minItems": _validators.minItems,
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u"minLength": _validators.minLength,
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u"minimum": _legacy_validators.minimum_draft3_draft4,
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u"pattern": _validators.pattern,
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u"patternProperties": _validators.patternProperties,
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u"properties": _legacy_validators.properties_draft3,
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u"type": _legacy_validators.type_draft3,
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u"uniqueItems": _validators.uniqueItems,
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},
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type_checker=_types.draft3_type_checker,
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version="draft3",
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id_of=lambda schema: schema.get(u"id", ""),
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)
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Draft4Validator = create(
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meta_schema=_utils.load_schema("draft4"),
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validators={
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u"$ref": _validators.ref,
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u"additionalItems": _validators.additionalItems,
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u"additionalProperties": _validators.additionalProperties,
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u"allOf": _validators.allOf,
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u"anyOf": _validators.anyOf,
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u"dependencies": _validators.dependencies,
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u"enum": _validators.enum,
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u"format": _validators.format,
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u"items": _legacy_validators.items_draft3_draft4,
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u"maxItems": _validators.maxItems,
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u"maxLength": _validators.maxLength,
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u"maxProperties": _validators.maxProperties,
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u"maximum": _legacy_validators.maximum_draft3_draft4,
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u"minItems": _validators.minItems,
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u"minLength": _validators.minLength,
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u"minProperties": _validators.minProperties,
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u"minimum": _legacy_validators.minimum_draft3_draft4,
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u"multipleOf": _validators.multipleOf,
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u"not": _validators.not_,
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u"oneOf": _validators.oneOf,
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u"pattern": _validators.pattern,
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u"patternProperties": _validators.patternProperties,
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u"properties": _validators.properties,
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u"required": _validators.required,
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u"type": _validators.type,
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u"uniqueItems": _validators.uniqueItems,
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},
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type_checker=_types.draft4_type_checker,
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version="draft4",
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id_of=lambda schema: schema.get(u"id", ""),
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)
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Draft6Validator = create(
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meta_schema=_utils.load_schema("draft6"),
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validators={
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u"$ref": _validators.ref,
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u"additionalItems": _validators.additionalItems,
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u"additionalProperties": _validators.additionalProperties,
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u"allOf": _validators.allOf,
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u"anyOf": _validators.anyOf,
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u"const": _validators.const,
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u"contains": _validators.contains,
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u"dependencies": _validators.dependencies,
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u"enum": _validators.enum,
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u"exclusiveMaximum": _validators.exclusiveMaximum,
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u"exclusiveMinimum": _validators.exclusiveMinimum,
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u"format": _validators.format,
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u"items": _validators.items,
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u"maxItems": _validators.maxItems,
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u"maxLength": _validators.maxLength,
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u"maxProperties": _validators.maxProperties,
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u"maximum": _validators.maximum,
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u"minItems": _validators.minItems,
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u"minLength": _validators.minLength,
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u"minProperties": _validators.minProperties,
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u"minimum": _validators.minimum,
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u"multipleOf": _validators.multipleOf,
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u"not": _validators.not_,
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u"oneOf": _validators.oneOf,
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u"pattern": _validators.pattern,
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u"patternProperties": _validators.patternProperties,
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u"properties": _validators.properties,
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u"propertyNames": _validators.propertyNames,
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u"required": _validators.required,
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u"type": _validators.type,
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u"uniqueItems": _validators.uniqueItems,
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},
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type_checker=_types.draft6_type_checker,
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version="draft6",
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)
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Draft7Validator = create(
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meta_schema=_utils.load_schema("draft7"),
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validators={
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u"$ref": _validators.ref,
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u"additionalItems": _validators.additionalItems,
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u"additionalProperties": _validators.additionalProperties,
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u"allOf": _validators.allOf,
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u"anyOf": _validators.anyOf,
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u"const": _validators.const,
|
|
u"contains": _validators.contains,
|
|
u"dependencies": _validators.dependencies,
|
|
u"enum": _validators.enum,
|
|
u"exclusiveMaximum": _validators.exclusiveMaximum,
|
|
u"exclusiveMinimum": _validators.exclusiveMinimum,
|
|
u"format": _validators.format,
|
|
u"if": _validators.if_,
|
|
u"items": _validators.items,
|
|
u"maxItems": _validators.maxItems,
|
|
u"maxLength": _validators.maxLength,
|
|
u"maxProperties": _validators.maxProperties,
|
|
u"maximum": _validators.maximum,
|
|
u"minItems": _validators.minItems,
|
|
u"minLength": _validators.minLength,
|
|
u"minProperties": _validators.minProperties,
|
|
u"minimum": _validators.minimum,
|
|
u"multipleOf": _validators.multipleOf,
|
|
u"oneOf": _validators.oneOf,
|
|
u"not": _validators.not_,
|
|
u"pattern": _validators.pattern,
|
|
u"patternProperties": _validators.patternProperties,
|
|
u"properties": _validators.properties,
|
|
u"propertyNames": _validators.propertyNames,
|
|
u"required": _validators.required,
|
|
u"type": _validators.type,
|
|
u"uniqueItems": _validators.uniqueItems,
|
|
},
|
|
type_checker=_types.draft7_type_checker,
|
|
version="draft7",
|
|
)
|
|
|
|
_LATEST_VERSION = Draft7Validator
|
|
|
|
|
|
class RefResolver(object):
|
|
"""
|
|
Resolve JSON References.
|
|
|
|
Arguments:
|
|
|
|
base_uri (str):
|
|
|
|
The URI of the referring document
|
|
|
|
referrer:
|
|
|
|
The actual referring document
|
|
|
|
store (dict):
|
|
|
|
A mapping from URIs to documents to cache
|
|
|
|
cache_remote (bool):
|
|
|
|
Whether remote refs should be cached after first resolution
|
|
|
|
handlers (dict):
|
|
|
|
A mapping from URI schemes to functions that should be used
|
|
to retrieve them
|
|
|
|
urljoin_cache (:func:`functools.lru_cache`):
|
|
|
|
A cache that will be used for caching the results of joining
|
|
the resolution scope to subscopes.
|
|
|
|
remote_cache (:func:`functools.lru_cache`):
|
|
|
|
A cache that will be used for caching the results of
|
|
resolved remote URLs.
|
|
|
|
Attributes:
|
|
|
|
cache_remote (bool):
|
|
|
|
Whether remote refs should be cached after first resolution
|
|
"""
|
|
|
|
def __init__(
|
|
self,
|
|
base_uri,
|
|
referrer,
|
|
store=(),
|
|
cache_remote=True,
|
|
handlers=(),
|
|
urljoin_cache=None,
|
|
remote_cache=None,
|
|
):
|
|
if urljoin_cache is None:
|
|
urljoin_cache = lru_cache(1024)(urljoin)
|
|
if remote_cache is None:
|
|
remote_cache = lru_cache(1024)(self.resolve_from_url)
|
|
|
|
self.referrer = referrer
|
|
self.cache_remote = cache_remote
|
|
self.handlers = dict(handlers)
|
|
|
|
self._scopes_stack = [base_uri]
|
|
self.store = _utils.URIDict(
|
|
(id, validator.META_SCHEMA)
|
|
for id, validator in iteritems(meta_schemas)
|
|
)
|
|
self.store.update(store)
|
|
self.store[base_uri] = referrer
|
|
|
|
self._urljoin_cache = urljoin_cache
|
|
self._remote_cache = remote_cache
|
|
|
|
@classmethod
|
|
def from_schema(cls, schema, id_of=_id_of, *args, **kwargs):
|
|
"""
|
|
Construct a resolver from a JSON schema object.
|
|
|
|
Arguments:
|
|
|
|
schema:
|
|
|
|
the referring schema
|
|
|
|
Returns:
|
|
|
|
`RefResolver`
|
|
"""
|
|
|
|
return cls(base_uri=id_of(schema), referrer=schema, *args, **kwargs)
|
|
|
|
def push_scope(self, scope):
|
|
"""
|
|
Enter a given sub-scope.
|
|
|
|
Treats further dereferences as being performed underneath the
|
|
given scope.
|
|
"""
|
|
self._scopes_stack.append(
|
|
self._urljoin_cache(self.resolution_scope, scope),
|
|
)
|
|
|
|
def pop_scope(self):
|
|
"""
|
|
Exit the most recent entered scope.
|
|
|
|
Treats further dereferences as being performed underneath the
|
|
original scope.
|
|
|
|
Don't call this method more times than `push_scope` has been
|
|
called.
|
|
"""
|
|
try:
|
|
self._scopes_stack.pop()
|
|
except IndexError:
|
|
raise exceptions.RefResolutionError(
|
|
"Failed to pop the scope from an empty stack. "
|
|
"`pop_scope()` should only be called once for every "
|
|
"`push_scope()`"
|
|
)
|
|
|
|
@property
|
|
def resolution_scope(self):
|
|
"""
|
|
Retrieve the current resolution scope.
|
|
"""
|
|
return self._scopes_stack[-1]
|
|
|
|
@property
|
|
def base_uri(self):
|
|
"""
|
|
Retrieve the current base URI, not including any fragment.
|
|
"""
|
|
uri, _ = urldefrag(self.resolution_scope)
|
|
return uri
|
|
|
|
@contextlib.contextmanager
|
|
def in_scope(self, scope):
|
|
"""
|
|
Temporarily enter the given scope for the duration of the context.
|
|
"""
|
|
self.push_scope(scope)
|
|
try:
|
|
yield
|
|
finally:
|
|
self.pop_scope()
|
|
|
|
@contextlib.contextmanager
|
|
def resolving(self, ref):
|
|
"""
|
|
Resolve the given ``ref`` and enter its resolution scope.
|
|
|
|
Exits the scope on exit of this context manager.
|
|
|
|
Arguments:
|
|
|
|
ref (str):
|
|
|
|
The reference to resolve
|
|
"""
|
|
|
|
url, resolved = self.resolve(ref)
|
|
self.push_scope(url)
|
|
try:
|
|
yield resolved
|
|
finally:
|
|
self.pop_scope()
|
|
|
|
def resolve(self, ref):
|
|
"""
|
|
Resolve the given reference.
|
|
"""
|
|
url = self._urljoin_cache(self.resolution_scope, ref)
|
|
return url, self._remote_cache(url)
|
|
|
|
def resolve_from_url(self, url):
|
|
"""
|
|
Resolve the given remote URL.
|
|
"""
|
|
url, fragment = urldefrag(url)
|
|
try:
|
|
document = self.store[url]
|
|
except KeyError:
|
|
try:
|
|
document = self.resolve_remote(url)
|
|
except Exception as exc:
|
|
raise exceptions.RefResolutionError(exc)
|
|
|
|
return self.resolve_fragment(document, fragment)
|
|
|
|
def resolve_fragment(self, document, fragment):
|
|
"""
|
|
Resolve a ``fragment`` within the referenced ``document``.
|
|
|
|
Arguments:
|
|
|
|
document:
|
|
|
|
The referent document
|
|
|
|
fragment (str):
|
|
|
|
a URI fragment to resolve within it
|
|
"""
|
|
|
|
fragment = fragment.lstrip(u"/")
|
|
parts = unquote(fragment).split(u"/") if fragment else []
|
|
|
|
for part in parts:
|
|
part = part.replace(u"~1", u"/").replace(u"~0", u"~")
|
|
|
|
if isinstance(document, Sequence):
|
|
# Array indexes should be turned into integers
|
|
try:
|
|
part = int(part)
|
|
except ValueError:
|
|
pass
|
|
try:
|
|
document = document[part]
|
|
except (TypeError, LookupError):
|
|
raise exceptions.RefResolutionError(
|
|
"Unresolvable JSON pointer: %r" % fragment
|
|
)
|
|
|
|
return document
|
|
|
|
def resolve_remote(self, uri):
|
|
"""
|
|
Resolve a remote ``uri``.
|
|
|
|
If called directly, does not check the store first, but after
|
|
retrieving the document at the specified URI it will be saved in
|
|
the store if :attr:`cache_remote` is True.
|
|
|
|
.. note::
|
|
|
|
If the requests_ library is present, ``jsonschema`` will use it to
|
|
request the remote ``uri``, so that the correct encoding is
|
|
detected and used.
|
|
|
|
If it isn't, or if the scheme of the ``uri`` is not ``http`` or
|
|
``https``, UTF-8 is assumed.
|
|
|
|
Arguments:
|
|
|
|
uri (str):
|
|
|
|
The URI to resolve
|
|
|
|
Returns:
|
|
|
|
The retrieved document
|
|
|
|
.. _requests: https://pypi.org/project/requests/
|
|
"""
|
|
try:
|
|
import requests
|
|
except ImportError:
|
|
requests = None
|
|
|
|
scheme = urlsplit(uri).scheme
|
|
|
|
if scheme in self.handlers:
|
|
result = self.handlers[scheme](uri)
|
|
elif scheme in [u"http", u"https"] and requests:
|
|
# Requests has support for detecting the correct encoding of
|
|
# json over http
|
|
result = requests.get(uri).json()
|
|
else:
|
|
# Otherwise, pass off to urllib and assume utf-8
|
|
with urlopen(uri) as url:
|
|
result = json.loads(url.read().decode("utf-8"))
|
|
|
|
if self.cache_remote:
|
|
self.store[uri] = result
|
|
return result
|
|
|
|
|
|
def validate(instance, schema, cls=None, *args, **kwargs):
|
|
"""
|
|
Validate an instance under the given schema.
|
|
|
|
>>> validate([2, 3, 4], {"maxItems": 2})
|
|
Traceback (most recent call last):
|
|
...
|
|
ValidationError: [2, 3, 4] is too long
|
|
|
|
:func:`validate` will first verify that the provided schema is
|
|
itself valid, since not doing so can lead to less obvious error
|
|
messages and fail in less obvious or consistent ways.
|
|
|
|
If you know you have a valid schema already, especially if you
|
|
intend to validate multiple instances with the same schema, you
|
|
likely would prefer using the `IValidator.validate` method directly
|
|
on a specific validator (e.g. ``Draft7Validator.validate``).
|
|
|
|
|
|
Arguments:
|
|
|
|
instance:
|
|
|
|
The instance to validate
|
|
|
|
schema:
|
|
|
|
The schema to validate with
|
|
|
|
cls (IValidator):
|
|
|
|
The class that will be used to validate the instance.
|
|
|
|
If the ``cls`` argument is not provided, two things will happen
|
|
in accordance with the specification. First, if the schema has a
|
|
:validator:`$schema` property containing a known meta-schema [#]_
|
|
then the proper validator will be used. The specification recommends
|
|
that all schemas contain :validator:`$schema` properties for this
|
|
reason. If no :validator:`$schema` property is found, the default
|
|
validator class is the latest released draft.
|
|
|
|
Any other provided positional and keyword arguments will be passed
|
|
on when instantiating the ``cls``.
|
|
|
|
Raises:
|
|
|
|
`jsonschema.exceptions.ValidationError` if the instance
|
|
is invalid
|
|
|
|
`jsonschema.exceptions.SchemaError` if the schema itself
|
|
is invalid
|
|
|
|
.. rubric:: Footnotes
|
|
.. [#] known by a validator registered with
|
|
`jsonschema.validators.validates`
|
|
"""
|
|
if cls is None:
|
|
cls = validator_for(schema)
|
|
|
|
cls.check_schema(schema)
|
|
validator = cls(schema, *args, **kwargs)
|
|
error = exceptions.best_match(validator.iter_errors(instance))
|
|
if error is not None:
|
|
raise error
|
|
|
|
|
|
def validator_for(schema, default=_LATEST_VERSION):
|
|
"""
|
|
Retrieve the validator class appropriate for validating the given schema.
|
|
|
|
Uses the :validator:`$schema` property that should be present in the
|
|
given schema to look up the appropriate validator class.
|
|
|
|
Arguments:
|
|
|
|
schema (collections.Mapping or bool):
|
|
|
|
the schema to look at
|
|
|
|
default:
|
|
|
|
the default to return if the appropriate validator class
|
|
cannot be determined.
|
|
|
|
If unprovided, the default is to return the latest supported
|
|
draft.
|
|
"""
|
|
if schema is True or schema is False or u"$schema" not in schema:
|
|
return default
|
|
if schema[u"$schema"] not in meta_schemas:
|
|
warn(
|
|
(
|
|
"The metaschema specified by $schema was not found. "
|
|
"Using the latest draft to validate, but this will raise "
|
|
"an error in the future."
|
|
),
|
|
DeprecationWarning,
|
|
stacklevel=2,
|
|
)
|
|
return meta_schemas.get(schema[u"$schema"], _LATEST_VERSION)
|