from enum import Enum as PyEnum
import inspect
from functools import partial
from graphql import (
default_type_resolver,
get_introspection_query,
graphql,
graphql_sync,
introspection_types,
parse,
print_schema,
subscribe,
validate,
ExecutionResult,
GraphQLArgument,
GraphQLBoolean,
GraphQLError,
GraphQLEnumValue,
GraphQLField,
GraphQLFloat,
GraphQLID,
GraphQLInputField,
GraphQLInt,
GraphQLList,
GraphQLNonNull,
GraphQLObjectType,
GraphQLSchema,
GraphQLString,
)
from ..utils.str_converters import to_camel_case
from ..utils.get_unbound_function import get_unbound_function
from .definitions import (
GrapheneEnumType,
GrapheneGraphQLType,
GrapheneInputObjectType,
GrapheneInterfaceType,
GrapheneObjectType,
GrapheneScalarType,
GrapheneUnionType,
)
from .dynamic import Dynamic
from .enum import Enum
from .field import Field
from .inputobjecttype import InputObjectType
from .interface import Interface
from .objecttype import ObjectType
from .resolver import get_default_resolver
from .scalars import ID, Boolean, Float, Int, Scalar, String
from .structures import List, NonNull
from .union import Union
from .utils import get_field_as
introspection_query = get_introspection_query()
IntrospectionSchema = introspection_types["__Schema"]
def assert_valid_root_type(type_):
if type_ is None:
return
is_graphene_objecttype = inspect.isclass(type_) and issubclass(type_, ObjectType)
is_graphql_objecttype = isinstance(type_, GraphQLObjectType)
assert (
is_graphene_objecttype or is_graphql_objecttype
), f"Type {type_} is not a valid ObjectType."
def is_graphene_type(type_):
if isinstance(type_, (List, NonNull)):
return True
if inspect.isclass(type_) and issubclass(
type_, (ObjectType, InputObjectType, Scalar, Interface, Union, Enum)
):
return True
def is_type_of_from_possible_types(possible_types, root, _info):
return isinstance(root, possible_types)
# We use this resolver for subscriptions
def identity_resolve(root, info, **arguments):
return root
class TypeMap(dict):
def __init__(
self,
query=None,
mutation=None,
subscription=None,
types=None,
auto_camelcase=True,
):
assert_valid_root_type(query)
assert_valid_root_type(mutation)
assert_valid_root_type(subscription)
if types is None:
types = []
for type_ in types:
assert is_graphene_type(type_)
self.auto_camelcase = auto_camelcase
create_graphql_type = self.add_type
self.query = create_graphql_type(query) if query else None
self.mutation = create_graphql_type(mutation) if mutation else None
self.subscription = create_graphql_type(subscription) if subscription else None
self.types = [create_graphql_type(graphene_type) for graphene_type in types]
def add_type(self, graphene_type):
if inspect.isfunction(graphene_type):
graphene_type = graphene_type()
if isinstance(graphene_type, List):
return GraphQLList(self.add_type(graphene_type.of_type))
if isinstance(graphene_type, NonNull):
return GraphQLNonNull(self.add_type(graphene_type.of_type))
try:
name = graphene_type._meta.name
except AttributeError:
raise TypeError(f"Expected Graphene type, but received: {graphene_type}.")
graphql_type = self.get(name)
if graphql_type:
return graphql_type
if issubclass(graphene_type, ObjectType):
graphql_type = self.create_objecttype(graphene_type)
elif issubclass(graphene_type, InputObjectType):
graphql_type = self.create_inputobjecttype(graphene_type)
elif issubclass(graphene_type, Interface):
graphql_type = self.create_interface(graphene_type)
elif issubclass(graphene_type, Scalar):
graphql_type = self.create_scalar(graphene_type)
elif issubclass(graphene_type, Enum):
graphql_type = self.create_enum(graphene_type)
elif issubclass(graphene_type, Union):
graphql_type = self.construct_union(graphene_type)
else:
raise TypeError(f"Expected Graphene type, but received: {graphene_type}.")
self[name] = graphql_type
return graphql_type
@staticmethod
def create_scalar(graphene_type):
# We have a mapping to the original GraphQL types
# so there are no collisions.
_scalars = {
String: GraphQLString,
Int: GraphQLInt,
Float: GraphQLFloat,
Boolean: GraphQLBoolean,
ID: GraphQLID,
}
if graphene_type in _scalars:
return _scalars[graphene_type]
return GrapheneScalarType(
graphene_type=graphene_type,
name=graphene_type._meta.name,
description=graphene_type._meta.description,
serialize=getattr(graphene_type, "serialize", None),
parse_value=getattr(graphene_type, "parse_value", None),
parse_literal=getattr(graphene_type, "parse_literal", None),
)
@staticmethod
def create_enum(graphene_type):
values = {}
for name, value in graphene_type._meta.enum.__members__.items():
description = getattr(value, "description", None)
# if the "description" attribute is an Enum, it is likely an enum member
# called description, not a description property
if isinstance(description, PyEnum):
description = None
if not description and callable(graphene_type._meta.description):
description = graphene_type._meta.description(value)
deprecation_reason = getattr(value, "deprecation_reason", None)
if isinstance(deprecation_reason, PyEnum):
deprecation_reason = None
if not deprecation_reason and callable(
graphene_type._meta.deprecation_reason
):
deprecation_reason = graphene_type._meta.deprecation_reason(value)
values[name] = GraphQLEnumValue(
value=value,
description=description,
deprecation_reason=deprecation_reason,
)
type_description = (
graphene_type._meta.description(None)
if callable(graphene_type._meta.description)
else graphene_type._meta.description
)
return GrapheneEnumType(
graphene_type=graphene_type,
values=values,
name=graphene_type._meta.name,
description=type_description,
)
def create_objecttype(self, graphene_type):
create_graphql_type = self.add_type
def interfaces():
interfaces = []
for graphene_interface in graphene_type._meta.interfaces:
interface = create_graphql_type(graphene_interface)
assert interface.graphene_type == graphene_interface
interfaces.append(interface)
return interfaces
if graphene_type._meta.possible_types:
is_type_of = partial(
is_type_of_from_possible_types, graphene_type._meta.possible_types
)
else:
is_type_of = graphene_type.is_type_of
return GrapheneObjectType(
graphene_type=graphene_type,
name=graphene_type._meta.name,
description=graphene_type._meta.description,
fields=partial(self.create_fields_for_type, graphene_type),
is_type_of=is_type_of,
interfaces=interfaces,
)
def create_interface(self, graphene_type):
resolve_type = (
partial(
self.resolve_type, graphene_type.resolve_type, graphene_type._meta.name
)
if graphene_type.resolve_type
else None
)
def interfaces():
interfaces = []
for graphene_interface in graphene_type._meta.interfaces:
interface = self.add_type(graphene_interface)
assert interface.graphene_type == graphene_interface
interfaces.append(interface)
return interfaces
return GrapheneInterfaceType(
graphene_type=graphene_type,
name=graphene_type._meta.name,
description=graphene_type._meta.description,
fields=partial(self.create_fields_for_type, graphene_type),
interfaces=interfaces,
resolve_type=resolve_type,
)
def create_inputobjecttype(self, graphene_type):
return GrapheneInputObjectType(
graphene_type=graphene_type,
name=graphene_type._meta.name,
description=graphene_type._meta.description,
out_type=graphene_type._meta.container,
fields=partial(
self.create_fields_for_type, graphene_type, is_input_type=True
),
)
def construct_union(self, graphene_type):
create_graphql_type = self.add_type
def types():
union_types = []
for graphene_objecttype in graphene_type._meta.types:
object_type = create_graphql_type(graphene_objecttype)
assert object_type.graphene_type == graphene_objecttype
union_types.append(object_type)
return union_types
resolve_type = (
partial(
self.resolve_type, graphene_type.resolve_type, graphene_type._meta.name
)
if graphene_type.resolve_type
else None
)
return GrapheneUnionType(
graphene_type=graphene_type,
name=graphene_type._meta.name,
description=graphene_type._meta.description,
types=types,
resolve_type=resolve_type,
)
def get_name(self, name):
if self.auto_camelcase:
return to_camel_case(name)
return name
def create_fields_for_type(self, graphene_type, is_input_type=False):
create_graphql_type = self.add_type
fields = {}
for name, field in graphene_type._meta.fields.items():
if isinstance(field, Dynamic):
field = get_field_as(field.get_type(self), _as=Field)
if not field:
continue
field_type = create_graphql_type(field.type)
if is_input_type:
_field = GraphQLInputField(
field_type,
default_value=field.default_value,
out_name=name,
description=field.description,
deprecation_reason=field.deprecation_reason,
)
else:
args = {}
for arg_name, arg in field.args.items():
arg_type = create_graphql_type(arg.type)
processed_arg_name = arg.name or self.get_name(arg_name)
args[processed_arg_name] = GraphQLArgument(
arg_type,
out_name=arg_name,
description=arg.description,
default_value=arg.default_value,
deprecation_reason=arg.deprecation_reason,
)
subscribe = field.wrap_subscribe(
self.get_function_for_type(
graphene_type, f"subscribe_{name}", name, field.default_value
)
)
# If we are in a subscription, we use (by default) an
# identity-based resolver for the root, rather than the
# default resolver for objects/dicts.
if subscribe:
field_default_resolver = identity_resolve
elif issubclass(graphene_type, ObjectType):
default_resolver = (
graphene_type._meta.default_resolver or get_default_resolver()
)
field_default_resolver = partial(
default_resolver, name, field.default_value
)
else:
field_default_resolver = None
resolve = field.wrap_resolve(
self.get_function_for_type(
graphene_type, f"resolve_{name}", name, field.default_value
)
or field_default_resolver
)
_field = GraphQLField(
field_type,
args=args,
resolve=resolve,
subscribe=subscribe,
deprecation_reason=field.deprecation_reason,
description=field.description,
)
field_name = field.name or self.get_name(name)
fields[field_name] = _field
return fields
def get_function_for_type(self, graphene_type, func_name, name, default_value):
"""Gets a resolve or subscribe function for a given ObjectType"""
if not issubclass(graphene_type, ObjectType):
return
resolver = getattr(graphene_type, func_name, None)
if not resolver:
# If we don't find the resolver in the ObjectType class, then try to
# find it in each of the interfaces
interface_resolver = None
for interface in graphene_type._meta.interfaces:
if name not in interface._meta.fields:
continue
interface_resolver = getattr(interface, func_name, None)
if interface_resolver:
break
resolver = interface_resolver
# Only if is not decorated with classmethod
if resolver:
return get_unbound_function(resolver)
def resolve_type(self, resolve_type_func, type_name, root, info, _type):
type_ = resolve_type_func(root, info)
if inspect.isclass(type_) and issubclass(type_, ObjectType):
return type_._meta.name
return_type = self[type_name]
return default_type_resolver(root, info, return_type)
[docs]class Schema:
"""Schema Definition.
A Graphene Schema can execute operations (query, mutation, subscription) against the defined
types. For advanced purposes, the schema can be used to lookup type definitions and answer
questions about the types through introspection.
Args:
query (Type[ObjectType]): Root query *ObjectType*. Describes entry point for fields to *read*
data in your Schema.
mutation (Optional[Type[ObjectType]]): Root mutation *ObjectType*. Describes entry point for
fields to *create, update or delete* data in your API.
subscription (Optional[Type[ObjectType]]): Root subscription *ObjectType*. Describes entry point
for fields to receive continuous updates.
types (Optional[List[Type[ObjectType]]]): List of any types to include in schema that
may not be introspected through root types.
directives (List[GraphQLDirective], optional): List of custom directives to include in the
GraphQL schema. Defaults to only include directives defined by GraphQL spec (@include
and @skip) [GraphQLIncludeDirective, GraphQLSkipDirective].
auto_camelcase (bool): Fieldnames will be transformed in Schema's TypeMap from snake_case
to camelCase (preferred by GraphQL standard). Default True.
"""
def __init__(
self,
query=None,
mutation=None,
subscription=None,
types=None,
directives=None,
auto_camelcase=True,
):
self.query = query
self.mutation = mutation
self.subscription = subscription
type_map = TypeMap(
query, mutation, subscription, types, auto_camelcase=auto_camelcase
)
self.graphql_schema = GraphQLSchema(
type_map.query,
type_map.mutation,
type_map.subscription,
type_map.types,
directives,
)
def __str__(self):
return print_schema(self.graphql_schema)
def __getattr__(self, type_name):
"""
This function let the developer select a type in a given schema
by accessing its attrs.
Example: using schema.Query for accessing the "Query" type in the Schema
"""
_type = self.graphql_schema.get_type(type_name)
if _type is None:
raise AttributeError(f'Type "{type_name}" not found in the Schema')
if isinstance(_type, GrapheneGraphQLType):
return _type.graphene_type
return _type
def lazy(self, _type):
return lambda: self.get_type(_type)
[docs] def execute(self, *args, **kwargs):
"""Execute a GraphQL query on the schema.
Use the `graphql_sync` function from `graphql-core` to provide the result
for a query string. Most of the time this method will be called by one of the Graphene
:ref:`Integrations` via a web request.
Args:
request_string (str or Document): GraphQL request (query, mutation or subscription)
as string or parsed AST form from `graphql-core`.
root_value (Any, optional): Value to use as the parent value object when resolving
root types.
context_value (Any, optional): Value to be made available to all resolvers via
`info.context`. Can be used to share authorization, dataloaders or other
information needed to resolve an operation.
variable_values (dict, optional): If variables are used in the request string, they can
be provided in dictionary form mapping the variable name to the variable value.
operation_name (str, optional): If multiple operations are provided in the
request_string, an operation name must be provided for the result to be provided.
middleware (List[SupportsGraphQLMiddleware]): Supply request level middleware as
defined in `graphql-core`.
execution_context_class (ExecutionContext, optional): The execution context class
to use when resolving queries and mutations.
Returns:
:obj:`ExecutionResult` containing any data and errors for the operation.
"""
kwargs = normalize_execute_kwargs(kwargs)
return graphql_sync(self.graphql_schema, *args, **kwargs)
[docs] async def execute_async(self, *args, **kwargs):
"""Execute a GraphQL query on the schema asynchronously.
Same as `execute`, but uses `graphql` instead of `graphql_sync`.
"""
kwargs = normalize_execute_kwargs(kwargs)
return await graphql(self.graphql_schema, *args, **kwargs)
[docs] async def subscribe(self, query, *args, **kwargs):
"""Execute a GraphQL subscription on the schema asynchronously."""
# Do parsing
try:
document = parse(query)
except GraphQLError as error:
return ExecutionResult(data=None, errors=[error])
# Do validation
validation_errors = validate(self.graphql_schema, document)
if validation_errors:
return ExecutionResult(data=None, errors=validation_errors)
# Execute the query
kwargs = normalize_execute_kwargs(kwargs)
return await subscribe(self.graphql_schema, document, *args, **kwargs)
def introspect(self):
introspection = self.execute(introspection_query)
if introspection.errors:
raise introspection.errors[0]
return introspection.data
def normalize_execute_kwargs(kwargs):
"""Replace alias names in keyword arguments for graphql()"""
if "root" in kwargs and "root_value" not in kwargs:
kwargs["root_value"] = kwargs.pop("root")
if "context" in kwargs and "context_value" not in kwargs:
kwargs["context_value"] = kwargs.pop("context")
if "variables" in kwargs and "variable_values" not in kwargs:
kwargs["variable_values"] = kwargs.pop("variables")
if "operation" in kwargs and "operation_name" not in kwargs:
kwargs["operation_name"] = kwargs.pop("operation")
return kwargs