ansible-later/env_27/lib/python2.7/site-packages/anyconfig/schema.py

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#
# Copyright (C) 2015 - 2017 Satoru SATOH <ssato redhat.com>
# License: MIT
#
"""anyconfig.schema module.
.. versionchanged:: 0.9.4
Change parameter passed to :func:`validate`, s/.*safe/ac_schema_safe/g
.. versionchanged:: 0.8.3
Replace format_checker with cls option
.. versionchanged:: 0.7.0
allow passing `ac_schema_strict` to API :func:`gen_schema` to generate more
strict and precise JSON schema object
.. versionadded:: 0.0.11
Added new API :func:`gen_schema` to generate schema object
.. versionadded:: 0.0.10
Added new API :func:`validate` to validate config with JSON schema
"""
from __future__ import absolute_import
try:
import jsonschema
except ImportError:
pass
import anyconfig.compat
import anyconfig.utils
_NA_MSG = "Validation module (jsonschema) is not available"
_SIMPLETYPE_MAP = {list: "array", tuple: "array",
bool: "boolean",
int: "integer", float: "number",
dict: "object",
str: "string"}
_SIMPLE_TYPES = (bool, int, float, str)
if not anyconfig.compat.IS_PYTHON_3:
try:
_SIMPLETYPE_MAP[unicode] = "string"
_SIMPLE_TYPES = (bool, int, float, str, unicode)
except NameError:
pass
def _validate_all(data, schema):
"""
See the descritpion of :func:`validate` for more details of parameters and
return value.
:seealso: https://python-jsonschema.readthedocs.io/en/latest/validate/,
a section of 'iter_errors' especially
"""
try:
vldtr = jsonschema.Draft4Validator(schema) # :raises: SchemaError, ...
errors = list(vldtr.iter_errors(data))
return (not errors, [err.message for err in errors])
except NameError:
return (True, _NA_MSG)
return (True, '')
def _validate(data, schema, ac_schema_safe=True, **options):
"""
See the descritpion of :func:`validate` for more details of parameters and
return value.
Validate target object `data` with given schema object.
"""
try:
jsonschema.validate(data, schema, **options)
return (True, '')
except NameError:
return (True, _NA_MSG)
except (jsonschema.ValidationError, jsonschema.SchemaError,
Exception) as exc:
if ac_schema_safe:
return (False, str(exc)) # Validation was failed.
raise
return (True, '')
def validate(data, schema, ac_schema_safe=True, ac_schema_errors=False,
**options):
"""
Validate target object with given schema object, loaded from JSON schema.
See also: https://python-jsonschema.readthedocs.org/en/latest/validate/
:parae data: Target object (a dict or a dict-like object) to validate
:param schema: Schema object (a dict or a dict-like object)
instantiated from schema JSON file or schema JSON string
:param options: Other keyword options such as:
- ac_schema_safe: Exception (jsonschema.ValidationError or
jsonschema.SchemaError or others) will be thrown during validation
process due to any validation or related errors. However, these will
be catched by default, and will be re-raised if `ac_safe` is False.
- ac_schema_errors: Lazily yield each of the validation errors and
returns all of them if validation fails.
:return: (True if validation succeeded else False, error message[s])
"""
options = anyconfig.utils.filter_options(("cls", ), options)
if ac_schema_errors:
return _validate_all(data, schema, **options)
return _validate(data, schema, ac_schema_safe, **options)
def _process_options(**options):
"""
Helper function to process keyword arguments passed to gen_schema.
:return: A tuple of (typemap :: dict, strict :: bool)
"""
return (options.get("ac_schema_typemap", _SIMPLETYPE_MAP),
bool(options.get("ac_schema_strict", False)))
def array_to_schema(arr, **options):
"""
Generate a JSON schema object with type annotation added for given object.
:param arr: Array of mapping objects like dicts
:param options: Other keyword options such as:
- ac_schema_strict: True if more strict (precise) schema is needed
- ac_schema_typemap: Type to JSON schema type mappings
:return: Another mapping objects represents JSON schema of items
"""
(typemap, strict) = _process_options(**options)
arr = list(arr)
scm = dict(type=typemap[list],
items=gen_schema(arr[0] if arr else "str", **options))
if strict:
nitems = len(arr)
scm["minItems"] = nitems
scm["uniqueItems"] = len(set(arr)) == nitems
return scm
def object_to_schema(obj, **options):
"""
Generate a node represents JSON schema object with type annotation added
for given object node.
:param obj: mapping object such like a dict
:param options: Other keyword options such as:
- ac_schema_strict: True if more strict (precise) schema is needed
- ac_schema_typemap: Type to JSON schema type mappings
:yield: Another mapping objects represents JSON schema of object
"""
(typemap, strict) = _process_options(**options)
props = dict((k, gen_schema(v, **options)) for k, v in obj.items())
scm = dict(type=typemap[dict], properties=props)
if strict:
scm["required"] = sorted(props.keys())
return scm
def gen_schema(data, **options):
"""
Generate a node represents JSON schema object with type annotation added
for given object node.
:param data: Configuration data object (dict[-like] or namedtuple)
:param options: Other keyword options such as:
- ac_schema_strict: True if more strict (precise) schema is needed
- ac_schema_typemap: Type to JSON schema type mappings
:return: A dict represents JSON schema of this node
"""
if data is None:
return dict(type="null")
_type = type(data)
if _type in _SIMPLE_TYPES:
typemap = options.get("ac_schema_typemap", _SIMPLETYPE_MAP)
scm = dict(type=typemap[_type])
elif anyconfig.utils.is_dict_like(data):
scm = object_to_schema(data, **options)
elif anyconfig.utils.is_list_like(data):
scm = array_to_schema(data, **options)
return scm
# vim:sw=4:ts=4:et: