django-rest-framework/rest_framework/schemas/inspectors.py
Carlton Gibson 37f210a455
Added OpenAPI Schema Generation. (#6532)
Co-authored-by: Lucidiot <lucidiot@protonmail.com>
Co-authored-by: dongfangtianyu <dongfangtianyu@qq.com>
2019-05-13 16:07:03 +02:00

80 lines
2.3 KiB
Python

"""
inspectors.py # Per-endpoint view introspection
See schemas.__init__.py for package overview.
"""
from weakref import WeakKeyDictionary
from rest_framework.settings import api_settings
class ViewInspector:
"""
Descriptor class on APIView.
Provide subclass for per-view schema generation
"""
def __init__(self):
self.instance_schemas = WeakKeyDictionary()
def __get__(self, instance, owner):
"""
Enables `ViewInspector` as a Python _Descriptor_.
This is how `view.schema` knows about `view`.
`__get__` is called when the descriptor is accessed on the owner.
(That will be when view.schema is called in our case.)
`owner` is always the owner class. (An APIView, or subclass for us.)
`instance` is the view instance or `None` if accessed from the class,
rather than an instance.
See: https://docs.python.org/3/howto/descriptor.html for info on
descriptor usage.
"""
if instance in self.instance_schemas:
return self.instance_schemas[instance]
self.view = instance
return self
def __set__(self, instance, other):
self.instance_schemas[instance] = other
if other is not None:
other.view = instance
@property
def view(self):
"""View property."""
assert self._view is not None, (
"Schema generation REQUIRES a view instance. (Hint: you accessed "
"`schema` from the view class rather than an instance.)"
)
return self._view
@view.setter
def view(self, value):
self._view = value
@view.deleter
def view(self):
self._view = None
class DefaultSchema(ViewInspector):
"""Allows overriding AutoSchema using DEFAULT_SCHEMA_CLASS setting"""
def __get__(self, instance, owner):
result = super().__get__(instance, owner)
if not isinstance(result, DefaultSchema):
return result
inspector_class = api_settings.DEFAULT_SCHEMA_CLASS
assert issubclass(inspector_class, ViewInspector), (
"DEFAULT_SCHEMA_CLASS must be set to a ViewInspector (usually an AutoSchema) subclass"
)
inspector = inspector_class()
inspector.view = instance
return inspector