awx/lib/vendor/extendedmodelresource.py

621 lines
24 KiB
Python

# modified version of https://github.com/tryolabs/django-tastypie-extendedmodelresource
# from PyPi, tweaked to make it work with latest tastypie
from django.http import HttpResponse
from django.core.exceptions import ObjectDoesNotExist, MultipleObjectsReturned
from django.core.urlresolvers import get_script_prefix, resolve, Resolver404
from django.conf.urls.defaults import patterns, url, include
from tastypie import fields, http
from tastypie.exceptions import NotFound, ImmediateHttpResponse
from tastypie.resources import ResourceOptions, ModelDeclarativeMetaclass, \
ModelResource, convert_post_to_put
from tastypie.utils import trailing_slash
class ExtendedDeclarativeMetaclass(ModelDeclarativeMetaclass):
"""
Same as ``DeclarativeMetaclass`` but uses ``AnyIdAttributeResourceOptions``
instead of ``ResourceOptions`` and adds support for multiple nested fields
defined in a "Nested" class (the same way as "Meta") inside the resources.
"""
def __new__(cls, name, bases, attrs):
new_class = super(ExtendedDeclarativeMetaclass, cls).__new__(cls,
name, bases, attrs)
opts = getattr(new_class, 'Meta', None)
new_class._meta = ResourceOptions(opts)
# Will map nested fields names to the actual fields
nested_fields = {}
nested_class = getattr(new_class, 'Nested', None)
if nested_class is not None:
for field_name in dir(nested_class):
if not field_name.startswith('_'): # No internals
field_object = getattr(nested_class, field_name)
nested_fields[field_name] = field_object
if hasattr(field_object, 'contribute_to_class'):
field_object.contribute_to_class(new_class,
field_name)
new_class._nested = nested_fields
return new_class
class ExtendedModelResource(ModelResource):
__metaclass__ = ExtendedDeclarativeMetaclass
def remove_api_resource_names(self, url_dict):
"""
Given a dictionary of regex matches from a URLconf, removes
``api_name`` and/or ``resource_name`` if found.
This is useful for converting URLconf matches into something suitable
for data lookup. For example::
Model.objects.filter(**self.remove_api_resource_names(matches))
"""
kwargs_subset = url_dict.copy()
for key in ['api_name', 'resource_name', 'related_manager',
'child_object', 'parent_resource', 'nested_name',
'parent_object']:
try:
del(kwargs_subset[key])
except KeyError:
pass
return kwargs_subset
def get_detail_uri_name_regex(self):
"""
Return the regular expression to which the id attribute used in
resource URLs should match.
By default we admit any alphanumeric value and "-", but you may
override this function and provide your own.
"""
return r'\w[\w-]*'
def base_urls(self):
"""
Same as the original ``base_urls`` but supports using the custom
regex for the ``detail_uri_name`` attribute of the objects.
"""
# Due to the way Django parses URLs, ``get_multiple``
# won't work without a trailing slash.
return [
url(r"^(?P<resource_name>%s)%s$" %
(self._meta.resource_name, trailing_slash()),
self.wrap_view('dispatch_list'),
name="api_dispatch_list"),
url(r"^(?P<resource_name>%s)/schema%s$" %
(self._meta.resource_name, trailing_slash()),
self.wrap_view('get_schema'),
name="api_get_schema"),
url(r"^(?P<resource_name>%s)/set/(?P<%s_list>(%s;?)*)/$" %
(self._meta.resource_name,
self._meta.detail_uri_name,
self.get_detail_uri_name_regex()),
self.wrap_view('get_multiple'),
name="api_get_multiple"),
url(r"^(?P<resource_name>%s)/(?P<%s>%s)%s$" %
(self._meta.resource_name,
self._meta.detail_uri_name,
self.get_detail_uri_name_regex(),
trailing_slash()),
self.wrap_view('dispatch_detail'),
name="api_dispatch_detail"),
]
def nested_urls(self):
"""
Return the list of all urls nested under the detail view of a resource.
Each resource listed as Nested will generate one url.
"""
def get_nested_url(nested_name):
return url(r"^(?P<resource_name>%s)/(?P<%s>%s)/"
r"(?P<nested_name>%s)%s$" %
(self._meta.resource_name,
self._meta.detail_uri_name,
self.get_detail_uri_name_regex(),
nested_name,
trailing_slash()),
self.wrap_view('dispatch_nested'),
name='api_dispatch_nested')
return [get_nested_url(nested_name)
for nested_name in self._nested.keys()]
def detail_actions(self):
"""
Return urls of custom actions to be performed on the detail view of a
resource. These urls will be appended to the url of the detail view.
This allows a finer control by providing a custom view for each of
these actions in the resource.
A resource should override this method and provide its own list of
detail actions urls, if needed.
For example:
return [
url(r"^show_schema/$", self.wrap_view('get_schema'),
name="api_get_schema")
]
will add show schema capabilities to a detail resource URI (ie.
/api/user/3/show_schema/ will work just like /api/user/schema/).
"""
return []
def detail_actions_urlpatterns(self):
"""
Return the url patterns corresponding to the detail actions available
on this resource.
"""
if self.detail_actions():
detail_url = "^(?P<resource_name>%s)/(?P<%s>%s)/" % (
self._meta.resource_name,
self._meta.detail_uri_name,
self.get_detail_uri_name_regex()
)
return patterns('', (detail_url, include(self.detail_actions())))
return []
@property
def urls(self):
"""
The endpoints this ``Resource`` responds to.
Same as the original ``urls`` attribute but supports nested urls as
well as detail actions urls.
"""
urls = self.override_urls() + self.base_urls() + self.nested_urls()
return patterns('', *urls) + self.detail_actions_urlpatterns()
def is_authorized_over_parent(self, request, parent_object):
"""
Allows the ``Authorization`` class to check if a request to a nested
resource has permissions over the parent.
Will call the ``is_authorized_parent`` function of the
``Authorization`` class.
"""
if hasattr(self._meta.authorization, 'is_authorized_parent'):
return self._meta.authorization.is_authorized_parent(request,
parent_object)
return True
def parent_obj_get(self, request=None, **kwargs):
"""
Same as the original ``obj_get`` but called when a nested resource
wants to get its parent.
Will check authorization to see if the request is allowed to act on
the parent resource.
"""
parent_object = self.get_object_list(request).get(**kwargs)
# If I am not authorized for the parent
if not self.is_authorized_over_parent(request, parent_object):
stringified_kwargs = ', '.join(["%s=%s" % (k, v)
for k, v in kwargs.items()])
raise self._meta.object_class.DoesNotExist("Couldn't find an "
"instance of '%s' which matched '%s'." %
(self._meta.object_class.__name__, stringified_kwargs))
return parent_object
def parent_cached_obj_get(self, request=None, **kwargs):
"""
Same as the original ``cached_obj_get`` but called when a nested
resource wants to get its parent.
"""
cache_key = self.generate_cache_key('detail', **kwargs)
bundle = self._meta.cache.get(cache_key)
if bundle is None:
bundle = self.parent_obj_get(request=request, **kwargs)
self._meta.cache.set(cache_key, bundle)
return bundle
def get_via_uri_resolver(self, uri):
"""
Do the work of the original ``get_via_uri`` except calling ``obj_get``.
Use this as a helper function.
"""
prefix = get_script_prefix()
chomped_uri = uri
if prefix and chomped_uri.startswith(prefix):
chomped_uri = chomped_uri[len(prefix) - 1:]
try:
_view, _args, kwargs = resolve(chomped_uri)
except Resolver404:
raise NotFound("The URL provided '%s' was not a link to a valid "
"resource." % uri)
return kwargs
def get_nested_via_uri(self, uri, parent_resource,
parent_object, nested_name, request=None):
"""
Obtain a nested resource from an uri, a parent resource and a parent
object.
Calls ``obj_get`` which handles the authorization checks.
"""
# TODO: improve this to get parent resource & object from uri too?
kwargs = self.get_via_uri_resolver(uri)
return self.obj_get(nested_name=nested_name,
parent_resource=parent_resource,
parent_object=parent_object,
request=request,
**self.remove_api_resource_names(kwargs))
def get_via_uri_no_auth_check(self, uri, request=None):
"""
Obtain a nested resource from an uri, a parent resource and a
parent object.
Does *not* do authorization checks, those must be performed manually.
This function is useful be called from custom views over a resource
which need access to objects and can do the check of permissions
theirselves.
"""
kwargs = self.get_via_uri_resolver(uri)
return self.obj_get_no_auth_check(request=request,
**self.remove_api_resource_names(kwargs))
def obj_get(self, request=None, **kwargs):
"""
Same as the original ``obj_get`` but knows when it is being called to
get an object from a nested resource uri.
Performs authorization checks in every case.
"""
try:
nested_name = kwargs.pop('nested_name', None)
parent_resource = kwargs.pop('parent_resource', None)
parent_object = kwargs.pop('parent_object', None)
bundle = kwargs.pop('bundle', None) # MPD: fixup
base_object_list = self.get_object_list(request).filter(**kwargs)
if nested_name is not None:
# TODO: throw exception if parent_resource or parent_object are
# None
object_list = self.apply_nested_authorization_limits(request,
nested_name, parent_resource,
parent_object, base_object_list)
else:
object_list = self.apply_authorization_limits(request,
base_object_list)
stringified_kwargs = ', '.join(["%s=%s" % (k, v)
for k, v in kwargs.items()])
if len(object_list) <= 0:
raise self._meta.object_class.DoesNotExist("Couldn't find an "
"instance of '%s' which matched '%s'." %
(self._meta.object_class.__name__,
stringified_kwargs))
elif len(object_list) > 1:
raise MultipleObjectsReturned("More than '%s' matched '%s'." %
(self._meta.object_class.__name__, stringified_kwargs))
return object_list[0]
except ValueError:
raise NotFound("Invalid resource lookup data provided (mismatched "
"type).")
def obj_get_no_auth_check(self, request=None, **kwargs):
"""
Same as the original ``obj_get`` knows when it is being called to get
a nested resource.
Does *not* do authorization checks.
"""
# TODO: merge this and original obj_get and use another argument in
# kwargs to know if we should check for auth?
try:
object_list = self.get_object_list(request).filter(**kwargs)
stringified_kwargs = ', '.join(["%s=%s" % (k, v)
for k, v in kwargs.items()])
if len(object_list) <= 0:
raise self._meta.object_class.DoesNotExist("Couldn't find an "
"instance of '%s' which matched '%s'." %
(self._meta.object_class.__name__,
stringified_kwargs))
elif len(object_list) > 1:
raise MultipleObjectsReturned("More than '%s' matched '%s'." %
(self._meta.object_class.__name__, stringified_kwargs))
return object_list[0]
except ValueError:
raise NotFound("Invalid resource lookup data provided (mismatched "
"type).")
def apply_nested_authorization_limits(self, request, nested_name,
parent_resource, parent_object,
object_list):
"""
Allows the ``Authorization`` class to further limit the object list.
Also a hook to customize per ``Resource``.
"""
method_name = 'apply_limits_nested_%s' % nested_name
if hasattr(parent_resource._meta.authorization, method_name):
method = getattr(parent_resource._meta.authorization, method_name)
object_list = method(request, parent_object, object_list)
return object_list
def dispatch_nested(self, request, **kwargs):
"""
Dispatch a request to the nested resource.
"""
# We don't check for is_authorized here since it will be
# parent_cached_obj_get which will check that we have permissions
# over the parent.
self.is_authenticated(request)
self.throttle_check(request)
nested_name = kwargs.pop('nested_name')
nested_field = self._nested[nested_name]
try:
obj = self.parent_cached_obj_get(request=request,
**self.remove_api_resource_names(kwargs))
except ObjectDoesNotExist:
return http.HttpNotFound()
except MultipleObjectsReturned:
return http.HttpMultipleChoices("More than one parent resource is "
"found at this URI.")
# The nested resource needs to get the api_name from its parent because
# it is possible that the resource being used as nested is not
# registered in the API (ie. it can only be used as nested)
nested_resource = nested_field.to_class()
nested_resource._meta.api_name = self._meta.api_name
# TODO: comment further to make sense of this block
manager = None
try:
if isinstance(nested_field.attribute, basestring):
name = nested_field.attribute
manager = getattr(obj, name, None)
elif callable(nested_field.attribute):
manager = nested_field.attribute(obj)
else:
raise fields.ApiFieldError(
"The model '%r' has an empty attribute '%s' \
and doesn't allow a null value." % (
obj,
nested_field.attribute
)
)
except ObjectDoesNotExist:
pass
kwargs['nested_name'] = nested_name
kwargs['parent_resource'] = self
kwargs['parent_object'] = obj
if manager is None or not hasattr(manager, 'all'):
dispatch_type = 'detail'
kwargs['child_object'] = manager
else:
dispatch_type = 'list'
kwargs['related_manager'] = manager
return nested_resource.dispatch(
dispatch_type,
request,
**kwargs
)
# MPD: fixup upstream module
def is_authorized(self, request):
auth = getattr(self._meta, 'authorization')
if auth is not None:
return auth.is_authorized(request)
return False
def is_authorized_nested(self, request, nested_name,
parent_resource, parent_object, object=None):
"""
Handles checking of permissions to see if the user has authorization
to GET, POST, PUT, or DELETE this resource. If ``object`` is provided,
the authorization backend can apply additional row-level permissions
checking.
"""
# We use the authorization of the parent resource
method_name = 'is_authorized_nested_%s' % nested_name
if hasattr(parent_resource._meta.authorization, method_name):
method = getattr(parent_resource._meta.authorization, method_name)
auth_result = method(request, parent_object, object)
if isinstance(auth_result, HttpResponse):
raise ImmediateHttpResponse(response=auth_result)
if not auth_result is True:
raise ImmediateHttpResponse(response=http.HttpUnauthorized())
def dispatch(self, request_type, request, **kwargs):
"""
Same as the usual dispatch, but knows if its being called from a nested
resource.
"""
allowed_methods = getattr(self._meta,
"%s_allowed_methods" % request_type, None)
request_method = self.method_check(request, allowed=allowed_methods)
method = getattr(self, "%s_%s" % (request_method, request_type), None)
if method is None:
raise ImmediateHttpResponse(response=http.HttpNotImplemented())
self.is_authenticated(request)
self.throttle_check(request)
nested_name = kwargs.get('nested_name', None)
parent_resource = kwargs.get('parent_resource', None)
parent_object = kwargs.get('parent_object', None)
if nested_name is None:
self.is_authorized(request)
else:
self.is_authorized_nested(request, nested_name,
parent_resource,
parent_object)
# All clear. Process the request.
request = convert_post_to_put(request)
# MPD: fixup
response = method(request, **kwargs)
# Add the throttled request.
self.log_throttled_access(request)
# If what comes back isn't a ``HttpResponse``, assume that the
# request was accepted and that some action occurred. This also
# prevents Django from freaking out.
if not isinstance(response, HttpResponse):
return http.HttpNoContent()
return response
def obj_create(self, bundle, request=None, **kwargs):
related_manager = kwargs.pop('related_manager', None)
# Remove the other parameters used for the nested resources, if they
# are present.
kwargs.pop('nested_name', None)
kwargs.pop('parent_resource', None)
kwargs.pop('parent_object', None)
bundle.obj = self._meta.object_class()
for key, value in kwargs.items():
setattr(bundle.obj, key, value)
bundle = self.full_hydrate(bundle)
# Save FKs just in case.
self.save_related(bundle)
if related_manager is not None:
related_manager.add(bundle.obj)
# Save the main object.
bundle.obj.save()
# Now pick up the M2M bits.
m2m_bundle = self.hydrate_m2m(bundle)
self.save_m2m(m2m_bundle)
return bundle
def get_list(self, request, **kwargs):
"""
Returns a serialized list of resources.
Calls ``obj_get_list`` to provide the data, then handles that result
set and serializes it.
Should return a HttpResponse (200 OK).
"""
if 'related_manager' in kwargs:
manager = kwargs.pop('related_manager')
base_objects = manager.all()
nested_name = kwargs.pop('nested_name', None)
parent_resource = kwargs.pop('parent_resource', None)
parent_object = kwargs.pop('parent_object', None)
objects = self.apply_nested_authorization_limits(request,
nested_name, parent_resource, parent_object,
base_objects)
else:
# MPD: fixup compat with tastypie
basic_bundle = self.build_bundle(request=request)
objects = self.obj_get_list(
basic_bundle, # WAS: request=request,
**self.remove_api_resource_names(kwargs)
)
sorted_objects = self.apply_sorting(objects, options=request.GET)
paginator = self._meta.paginator_class(
request.GET, sorted_objects,
resource_uri=self.get_resource_uri(),
limit=self._meta.limit,
max_limit=self._meta.max_limit,
collection_name=self._meta.collection_name
)
to_be_serialized = paginator.page()
# Dehydrate the bundles in preparation for serialization.
bundles = []
for obj in to_be_serialized['objects']:
bundles.append(
self.full_dehydrate(
self.build_bundle(obj=obj, request=request)
)
)
to_be_serialized['objects'] = bundles
to_be_serialized = self.alter_list_data_to_serialize(request,
to_be_serialized)
return self.create_response(request, to_be_serialized)
def get_detail(self, request, **kwargs):
"""
Returns a single serialized resource.
Calls ``cached_obj_get/obj_get`` to provide the data, then handles that
result set and serializes it.
Should return a HttpResponse (200 OK).
"""
try:
# If call was made through Nested we should already have the
# child object.
if 'child_object' in kwargs:
obj = kwargs.pop('child_object', None)
if obj is None:
return http.HttpNotFound()
else:
# MPD: fixed up
basic_bundle = self.build_bundle(request=request)
# MPD: fixup
if 'bundle' in kwargs:
kwargs.pop('bundle')
obj = self.cached_obj_get(basic_bundle, **self.remove_api_resource_names(kwargs))
except AttributeError:
return http.HttpNotFound()
except ObjectDoesNotExist:
return http.HttpNotFound()
except MultipleObjectsReturned:
return http.HttpMultipleChoices("More than one resource is found "
"at this URI.")
bundle = self.build_bundle(obj=obj, request=request)
bundle = self.full_dehydrate(bundle)
bundle = self.alter_detail_data_to_serialize(request, bundle)
return self.create_response(request, bundle)