GraphQL queries in Django returning None

2019-07-23 08:06发布

问题:

Hi guys,

so i'm trying to use graphQL queries in django. Basically i have two apps, my 'api' app which contains everything i need to make the queries and another one called 'frontend' from which i call the api to use these queries.

I can use the GraphQL view to type queries in it and it works perfectly, but whenever i try to make the query, i get this : "OrderedDict([('users', None)])"

Result of my query in the GraphQl view

And for the code :

In 'api' my 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)

And the views.py that calls the app 'api' in my app frontend :

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})

The template :

<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>

and finally :

The web page result

and the error in the console :

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'

Any help is welcome guys, i just can't figure out why it isn't working since i'm logged and everything works just perfectly in the graphql view

ps : sorry if i made some mistake, english isn't my mother tongue

回答1:

Unless you're writing a test client, you probably should not be calling schema.execute from inside a Django view. But assuming that you have your reasons for doing this, your specific problem is that you're not passing the user when you invoke schema.execute in accueil view.

Have a look at the execute documentation and you'll see that you'll need to supply an optional argument for the context. Your code is not supplying a context, hence the info.context is None, as per your exception. Unfortunately, the example

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

is not Django-specific. But I think what works in a Django functional view is:

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