graphene-django/graphene_django/views.py

399 lines
14 KiB
Python

import inspect
import json
import re
from django.db import connection, transaction
from django.http import HttpResponse, HttpResponseNotAllowed
from django.http.response import HttpResponseBadRequest
from django.shortcuts import render
from django.utils.decorators import method_decorator
from django.views.decorators.csrf import ensure_csrf_cookie
from django.views.generic import View
from graphql import OperationType, get_operation_ast, parse, validate
from graphql.error import GraphQLError
from graphql.execution import ExecutionResult
from graphene import Schema
from graphql.execution.middleware import MiddlewareManager
from graphene_django.constants import MUTATION_ERRORS_FLAG
from graphene_django.utils.utils import set_rollback
from .settings import graphene_settings
class HttpError(Exception):
def __init__(self, response, message=None, *args, **kwargs):
self.response = response
self.message = message = message or response.content.decode()
super(HttpError, self).__init__(message, *args, **kwargs)
def get_accepted_content_types(request):
def qualify(x):
parts = x.split(";", 1)
if len(parts) == 2:
match = re.match(r"(^|;)q=(0(\.\d{,3})?|1(\.0{,3})?)(;|$)", parts[1])
if match:
return parts[0].strip(), float(match.group(2))
return parts[0].strip(), 1
raw_content_types = request.META.get("HTTP_ACCEPT", "*/*").split(",")
qualified_content_types = map(qualify, raw_content_types)
return list(
x[0] for x in sorted(qualified_content_types, key=lambda x: x[1], reverse=True)
)
def instantiate_middleware(middlewares):
for middleware in middlewares:
if inspect.isclass(middleware):
yield middleware()
continue
yield middleware
class GraphQLView(View):
graphiql_template = "graphene/graphiql.html"
# Polyfill for window.fetch.
whatwg_fetch_version = "3.6.2"
whatwg_fetch_sri = "sha256-+pQdxwAcHJdQ3e/9S4RK6g8ZkwdMgFQuHvLuN5uyk5c="
# React and ReactDOM.
react_version = "17.0.2"
react_sri = "sha256-Ipu/TQ50iCCVZBUsZyNJfxrDk0E2yhaEIz0vqI+kFG8="
react_dom_sri = "sha256-nbMykgB6tsOFJ7OdVmPpdqMFVk4ZsqWocT6issAPUF0="
# The GraphiQL React app.
graphiql_version = "1.4.1" # "1.0.3"
graphiql_sri = "sha256-JUMkXBQWZMfJ7fGEsTXalxVA10lzKOS9loXdLjwZKi4=" # "sha256-VR4buIDY9ZXSyCNFHFNik6uSe0MhigCzgN4u7moCOTk="
graphiql_css_sri = "sha256-Md3vdR7PDzWyo/aGfsFVF4tvS5/eAUWuIsg9QHUusCY=" # "sha256-LwqxjyZgqXDYbpxQJ5zLQeNcf7WVNSJ+r8yp2rnWE/E="
# The websocket transport library for subscriptions.
subscriptions_transport_ws_version = "0.9.18"
subscriptions_transport_ws_sri = (
"sha256-i0hAXd4PdJ/cHX3/8tIy/Q/qKiWr5WSTxMFuL9tACkw="
)
schema = None
graphiql = False
middleware = None
root_value = None
pretty = False
batch = False
subscription_path = None
execution_context_class = None
def __init__(
self,
schema=None,
middleware=None,
root_value=None,
graphiql=False,
pretty=False,
batch=False,
subscription_path=None,
execution_context_class=None,
):
if not schema:
schema = graphene_settings.SCHEMA
if middleware is None:
middleware = graphene_settings.MIDDLEWARE
self.schema = self.schema or schema
if middleware is not None:
if isinstance(middleware, MiddlewareManager):
self.middleware = middleware
else:
self.middleware = list(instantiate_middleware(middleware))
self.root_value = root_value
self.pretty = self.pretty or pretty
self.graphiql = self.graphiql or graphiql
self.batch = self.batch or batch
self.execution_context_class = execution_context_class
if subscription_path is None:
self.subscription_path = graphene_settings.SUBSCRIPTION_PATH
assert isinstance(
self.schema, Schema
), "A Schema is required to be provided to GraphQLView."
assert not all((graphiql, batch)), "Use either graphiql or batch processing"
# noinspection PyUnusedLocal
def get_root_value(self, request):
return self.root_value
def get_middleware(self, request):
return self.middleware
def get_context(self, request):
return request
@method_decorator(ensure_csrf_cookie)
def dispatch(self, request, *args, **kwargs):
try:
if request.method.lower() not in ("get", "post"):
raise HttpError(
HttpResponseNotAllowed(
["GET", "POST"], "GraphQL only supports GET and POST requests."
)
)
data = self.parse_body(request)
show_graphiql = self.graphiql and self.can_display_graphiql(request, data)
if show_graphiql:
return self.render_graphiql(
request,
# Dependency parameters.
whatwg_fetch_version=self.whatwg_fetch_version,
whatwg_fetch_sri=self.whatwg_fetch_sri,
react_version=self.react_version,
react_sri=self.react_sri,
react_dom_sri=self.react_dom_sri,
graphiql_version=self.graphiql_version,
graphiql_sri=self.graphiql_sri,
graphiql_css_sri=self.graphiql_css_sri,
subscriptions_transport_ws_version=self.subscriptions_transport_ws_version,
subscriptions_transport_ws_sri=self.subscriptions_transport_ws_sri,
# The SUBSCRIPTION_PATH setting.
subscription_path=self.subscription_path,
# GraphiQL headers tab,
graphiql_header_editor_enabled=graphene_settings.GRAPHIQL_HEADER_EDITOR_ENABLED,
graphiql_should_persist_headers=graphene_settings.GRAPHIQL_SHOULD_PERSIST_HEADERS,
)
if self.batch:
responses = [self.get_response(request, entry) for entry in data]
result = "[{}]".format(
",".join([response[0] for response in responses])
)
status_code = (
responses
and max(responses, key=lambda response: response[1])[1]
or 200
)
else:
result, status_code = self.get_response(request, data, show_graphiql)
return HttpResponse(
status=status_code, content=result, content_type="application/json"
)
except HttpError as e:
response = e.response
response["Content-Type"] = "application/json"
response.content = self.json_encode(
request, {"errors": [self.format_error(e)]}
)
return response
def get_response(self, request, data, show_graphiql=False):
query, variables, operation_name, id = self.get_graphql_params(request, data)
execution_result = self.execute_graphql_request(
request, data, query, variables, operation_name, show_graphiql
)
if getattr(request, MUTATION_ERRORS_FLAG, False) is True:
set_rollback()
status_code = 200
if execution_result:
response = {}
if execution_result.errors:
set_rollback()
response["errors"] = [
self.format_error(e) for e in execution_result.errors
]
if execution_result.errors and any(
not getattr(e, "path", None) for e in execution_result.errors
):
status_code = 400
else:
response["data"] = execution_result.data
if self.batch:
response["id"] = id
response["status"] = status_code
result = self.json_encode(request, response, pretty=show_graphiql)
else:
result = None
return result, status_code
def render_graphiql(self, request, **data):
return render(request, self.graphiql_template, data)
def json_encode(self, request, d, pretty=False):
if not (self.pretty or pretty) and not request.GET.get("pretty"):
return json.dumps(d, separators=(",", ":"))
return json.dumps(d, sort_keys=True, indent=2, separators=(",", ": "))
def parse_body(self, request):
content_type = self.get_content_type(request)
if content_type == "application/graphql":
return {"query": request.body.decode()}
elif content_type == "application/json":
# noinspection PyBroadException
try:
body = request.body.decode("utf-8")
except Exception as e:
raise HttpError(HttpResponseBadRequest(str(e)))
try:
request_json = json.loads(body)
if self.batch:
assert isinstance(request_json, list), (
"Batch requests should receive a list, but received {}."
).format(repr(request_json))
assert (
len(request_json) > 0
), "Received an empty list in the batch request."
else:
assert isinstance(
request_json, dict
), "The received data is not a valid JSON query."
return request_json
except AssertionError as e:
raise HttpError(HttpResponseBadRequest(str(e)))
except (TypeError, ValueError):
raise HttpError(HttpResponseBadRequest("POST body sent invalid JSON."))
elif content_type in [
"application/x-www-form-urlencoded",
"multipart/form-data",
]:
return request.POST
return {}
def execute_graphql_request(
self, request, data, query, variables, operation_name, show_graphiql=False
):
if not query:
if show_graphiql:
return None
raise HttpError(HttpResponseBadRequest("Must provide query string."))
try:
document = parse(query)
except Exception as e:
return ExecutionResult(errors=[e])
if request.method.lower() == "get":
operation_ast = get_operation_ast(document, operation_name)
if operation_ast and operation_ast.operation != OperationType.QUERY:
if show_graphiql:
return None
raise HttpError(
HttpResponseNotAllowed(
["POST"],
"Can only perform a {} operation from a POST request.".format(
operation_ast.operation.value
),
)
)
validation_errors = validate(self.schema.graphql_schema, document)
if validation_errors:
return ExecutionResult(data=None, errors=validation_errors)
try:
extra_options = {}
if self.execution_context_class:
extra_options["execution_context_class"] = self.execution_context_class
options = {
"source": query,
"root_value": self.get_root_value(request),
"variable_values": variables,
"operation_name": operation_name,
"context_value": self.get_context(request),
"middleware": self.get_middleware(request),
}
options.update(extra_options)
operation_ast = get_operation_ast(document, operation_name)
if (
operation_ast
and operation_ast.operation == OperationType.MUTATION
and (
graphene_settings.ATOMIC_MUTATIONS is True
or connection.settings_dict.get("ATOMIC_MUTATIONS", False) is True
)
):
with transaction.atomic():
result = self.schema.execute(**options)
if getattr(request, MUTATION_ERRORS_FLAG, False) is True:
transaction.set_rollback(True)
return result
return self.schema.execute(**options)
except Exception as e:
return ExecutionResult(errors=[e])
@classmethod
def can_display_graphiql(cls, request, data):
raw = "raw" in request.GET or "raw" in data
return not raw and cls.request_wants_html(request)
@classmethod
def request_wants_html(cls, request):
accepted = get_accepted_content_types(request)
accepted_length = len(accepted)
# the list will be ordered in preferred first - so we have to make
# sure the most preferred gets the highest number
html_priority = (
accepted_length - accepted.index("text/html")
if "text/html" in accepted
else 0
)
json_priority = (
accepted_length - accepted.index("application/json")
if "application/json" in accepted
else 0
)
return html_priority > json_priority
@staticmethod
def get_graphql_params(request, data):
query = request.GET.get("query") or data.get("query")
variables = request.GET.get("variables") or data.get("variables")
id = request.GET.get("id") or data.get("id")
if variables and isinstance(variables, str):
try:
variables = json.loads(variables)
except Exception:
raise HttpError(HttpResponseBadRequest("Variables are invalid JSON."))
operation_name = request.GET.get("operationName") or data.get("operationName")
if operation_name == "null":
operation_name = None
return query, variables, operation_name, id
@staticmethod
def format_error(error):
if isinstance(error, GraphQLError):
return error.formatted
return {"message": str(error)}
@staticmethod
def get_content_type(request):
meta = request.META
content_type = meta.get("CONTENT_TYPE", meta.get("HTTP_CONTENT_TYPE", ""))
return content_type.split(";", 1)[0].lower()