Django 中的 GraphQL 查询返回 None

Question

我正在尝试在 django 中使用 graphQL 查询。基本上我有两个应用程序，我的“api”应用程序包含我进行查询所需的一切，另一个称为“前端”，我从中调用 api 以使用这些查询。

我可以使用 GraphQL 视图在其中键入查询并且它运行良好，但是每当我尝试进行查询时，我都会得到以下信息：“OrderedDict([('users', None)])”

我在 GraphQl 视图中的查询结果

编码：

在“api”中，我的schema.py：

import graphene
import graphql_jwt
from graphene import relay, ObjectType, AbstractType, List, String, Field,InputObjectType
from graphene_django import DjangoObjectType
from graphene_django.filter import DjangoFilterConnectionField
from datetime import date, datetime
from django.contrib.auth.models import User
from django.contrib.auth import get_user_model

....

class Query(graphene.ObjectType):
    me = graphene.Field(UserType)
    users = graphene.List(UserType)
    profile = relay.Node.Field(ProfileNode)
    all_profiles = DjangoFilterConnectionField(ProfileNode)

    def resolve_users(self, info):
        ### Returns all users ###
        user = info.context.user
        if user.is_anonymous:
            raise Exception('Not logged!')
        if not user.is_superuser:
            raise Exception('premission denied')
        return User.objects.all()

    def resolve_me(self, info):
        ### Returns logged user ###
        user = info.context.user
        if user.is_anonymous:
            raise Exception('Not logged!')
        return user

    def resolve_all_profiles(self, info, **kwargs):
        ### Returns all profiles ###
        return Profile.objects.all()

.....

def execute(my_query):
    schema = graphene.Schema(query=Query)
    return schema.execute(my_query)

以及在我的应用程序前端调用应用程序“api”的views.py：

from django.shortcuts import render
import graphene
from api import schema
from django.contrib.auth import authenticate


def accueil(request):

    if request.user.is_authenticated:
        check = "I am logged"
    else:
        check = "I am not logged"

    result = schema.execute("""query {
                                users {
                                    id
                                    username
                                }
                            }""")

    return render(request, 'frontend/accueil.html', {'result' : result.data, 'check' : check})

模板：

<h1>OTC</h1>
<p> the users are : {{result}}</p>
<br/>
<p>{{check}}</p>
<a href="{%url 'login'  %}">login</a>
<a href="{%url 'logout' %}">logout</a>

最后：

网页结果

以及控制台中的错误：

An error occurred while resolving field Query.users
Traceback (most recent call last):
  File "/home/victor/myenv/lib/python3.5/site-packages/graphql/execution/executor.py", line 311, in resolve_or_error
    return executor.execute(resolve_fn, source, info, **args)
  File "/home/victor/myenv/lib/python3.5/site-packages/graphql/execution/executors/sync.py", line 7, in execute
    return fn(*args, **kwargs)
  File "/home/victor/poc2/poc2/api/schema.py", line 67, in resolve_users
    user = info.context.user
AttributeError: 'NoneType' object has no attribute 'user'
Traceback (most recent call last):
  File "/home/victor/myenv/lib/python3.5/site-packages/graphql/execution/executor.py", line 330, in complete_value_catching_error
    exe_context, return_type, field_asts, info, result)
  File "/home/victor/myenv/lib/python3.5/site-packages/graphql/execution/executor.py", line 383, in complete_value
    raise GraphQLLocatedError(field_asts, original_error=result)
graphql.error.located_error.GraphQLLocatedError: 'NoneType' object has no attribute 'user'

Answer 1

除非您正在编写测试客户端，否则您可能不应该schema.execute从 Django 视图内部调用。但是，假设你有你的理由这样做，您的具体问题是，你没有通过用户在调用schema.execute的accueil视图。

查看执行文档，您会发现您需要为上下文提供一个可选参数。您的代码没有提供上下文，因此根据您的例外情况info.context是 is None。不幸的是，这个例子

result = schema.execute('{ name }', context_value={'name': 'Syrus'})

不是特定于 Django 的。但我认为在 Django 功能视图中起作用的是：

result = schema.execute(query, context_value=request)