import copy
import json
import logging
from collections import OrderedDict
from django.utils.encoding import force_bytes
import yaml
try:
from swagger_spec_validator.common import SwaggerValidationError as SSVErr
from swagger_spec_validator.validator20 import validate_spec as validate_ssv
except ImportError: # pragma: no cover
validate_ssv = None
try:
from flex.core import parse as validate_flex
from flex.exceptions import ValidationError
except ImportError: # pragma: no cover
validate_flex = None
from . import openapi
from .errors import SwaggerValidationError
logger = logging.getLogger(__name__)
[docs]def _validate_flex(spec):
try:
validate_flex(spec)
except ValidationError as ex:
raise SwaggerValidationError(str(ex)) from ex
[docs]def _validate_swagger_spec_validator(spec):
try:
validate_ssv(spec)
except SSVErr as ex:
raise SwaggerValidationError(str(ex)) from ex
#:
VALIDATORS = {
"flex": _validate_flex if validate_flex else lambda s: None,
"ssv": _validate_swagger_spec_validator if validate_ssv else lambda s: None,
}
[docs]class _OpenAPICodec:
media_type = None
def __init__(self, validators):
self._validators = validators
@property
def validators(self):
"""List of validator names to apply"""
return self._validators
[docs] def encode(self, document):
"""Transform an :class:`.Swagger` object to a sequence of bytes.
Also performs validation and applies settings.
:param openapi.Swagger document: Swagger spec object as generated by :class:`.OpenAPISchemaGenerator`
:return: binary encoding of ``document``
:rtype: bytes
"""
if not isinstance(document, openapi.Swagger):
raise TypeError('Expected a `openapi.Swagger` instance')
spec = self.generate_swagger_object(document)
errors = {}
for validator in self.validators:
try:
# validate a deepcopy of the spec to prevent the validator from messing with it
# for example, swagger_spec_validator adds an x-scope property to all references
VALIDATORS[validator](copy.deepcopy(spec))
except SwaggerValidationError as e:
errors[validator] = str(e)
if errors:
exc = SwaggerValidationError("spec validation failed: {}".format(errors), errors, spec, self)
logger.warning(str(exc))
raise exc
return force_bytes(self._dump_dict(spec))
[docs] def encode_error(self, err):
"""Dump an error message into an encoding-appropriate sequence of bytes"""
return force_bytes(self._dump_dict(err))
[docs] def _dump_dict(self, spec):
"""Dump the given dictionary into its string representation.
:param dict spec: a python dict
:return: string representation of ``spec``
:rtype: str or bytes
"""
raise NotImplementedError("override this method")
[docs] def generate_swagger_object(self, swagger):
"""Generates the root Swagger object.
:param openapi.Swagger swagger: Swagger spec object as generated by :class:`.OpenAPISchemaGenerator`
:return: swagger spec as dict
:rtype: OrderedDict
"""
return swagger.as_odict()
[docs]class OpenAPICodecJson(_OpenAPICodec):
media_type = 'application/json'
def __init__(self, validators, pretty=False, media_type='application/json'):
super(OpenAPICodecJson, self).__init__(validators)
self.pretty = pretty
self.media_type = media_type
[docs] def _dump_dict(self, spec):
"""Dump ``spec`` into JSON.
:rtype: str"""
if self.pretty:
return f"{json.dumps(spec, indent=4, separators=(',', ': '), ensure_ascii=False)}\n"
else:
return json.dumps(spec, ensure_ascii=False)
YAML_MAP_TAG = u'tag:yaml.org,2002:map'
YamlDumper = getattr(yaml, 'CSafeDumper', yaml.SafeDumper)
YamlLoader = getattr(yaml, 'CSafeLoader', yaml.SafeLoader)
class SaneYamlDumper(YamlDumper):
"""YamlDumper class usable for dumping ``OrderedDict`` and list instances in a standard way."""
def ignore_aliases(self, data):
"""Disable YAML references."""
return True
def represent_odict(self, mapping, flow_style=None): # pragma: no cover
"""https://gist.github.com/miracle2k/3184458
Make PyYAML output an OrderedDict.
It will do so fine if you use yaml.dump(), but that generates ugly, non-standard YAML code.
To use yaml.safe_dump(), you need the following.
"""
tag = YAML_MAP_TAG
value = []
node = yaml.MappingNode(tag, value, flow_style=flow_style)
if self.alias_key is not None:
self.represented_objects[self.alias_key] = node
best_style = True
if hasattr(mapping, 'items'):
mapping = mapping.items()
for item_key, item_value in mapping:
node_key = self.represent_data(item_key)
node_value = self.represent_data(item_value)
if not (isinstance(node_key, yaml.ScalarNode) and not node_key.style):
best_style = False
if not (isinstance(node_value, yaml.ScalarNode) and not node_value.style):
best_style = False
value.append((node_key, node_value))
if flow_style is None:
if self.default_flow_style is not None:
node.flow_style = self.default_flow_style
else:
node.flow_style = best_style
return node
def represent_text(self, text):
if "\n" in text:
return self.represent_scalar('tag:yaml.org,2002:str', text, style='|')
return self.represent_scalar('tag:yaml.org,2002:str', text)
SaneYamlDumper.add_representer(bytes, SaneYamlDumper.represent_text)
SaneYamlDumper.add_representer(str, SaneYamlDumper.represent_text)
SaneYamlDumper.add_representer(OrderedDict, SaneYamlDumper.represent_odict)
SaneYamlDumper.add_multi_representer(OrderedDict, SaneYamlDumper.represent_odict)
[docs]def yaml_sane_dump(data, binary):
"""Dump the given data dictionary into a sane format:
* OrderedDicts are dumped as regular mappings instead of non-standard !!odict
* multi-line mapping style instead of json-like inline style
* list elements are indented into their parents
* YAML references/aliases are disabled
:param dict data: the data to be dumped
:param bool binary: True to return a utf-8 encoded binary object, False to return a string
:return: the serialized YAML
:rtype: str or bytes
"""
return yaml.dump(
data,
Dumper=SaneYamlDumper,
default_flow_style=False,
encoding='utf-8' if binary else None,
allow_unicode=binary,
sort_keys=False,
)
class SaneYamlLoader(YamlLoader):
def construct_odict(self, node, deep=False):
self.flatten_mapping(node)
return OrderedDict(self.construct_pairs(node))
SaneYamlLoader.add_constructor(YAML_MAP_TAG, SaneYamlLoader.construct_odict)
[docs]def yaml_sane_load(stream):
"""Load the given YAML stream while preserving the input order for mapping items.
:param stream: YAML stream (can be a string or a file-like object)
:rtype: OrderedDict
"""
return yaml.load(stream, Loader=SaneYamlLoader)
[docs]class OpenAPICodecYaml(_OpenAPICodec):
media_type = 'application/yaml'
def __init__(self, validators, media_type='application/yaml'):
super(OpenAPICodecYaml, self).__init__(validators)
self.media_type = media_type
[docs] def _dump_dict(self, spec):
"""Dump ``spec`` into YAML.
:rtype: bytes"""
return yaml_sane_dump(spec, binary=True)