django - ジャンゴでGmail APIを使用する

Question

私はDjangoに少し慣れていないので、pythonスクリプト（認証、gmailサービスの構築、gmailのクエリ）をdjangoアプリに変換するのに助けが必要です。Google django サンプルと、ここで指定したクラスhttps://developers.google.com/api-client-library/python/guide/djangoを使用しようとしていますが、少し混乱しています。どんな助けでも大歓迎です！以下のコードは、インデックスにアクセスしたときの認証フローを示していますが、Google プロファイルをクリックすると、結果のページにエラーが表示され"ValueError at /app/ ます。

Traceback:
File "/Library/Python/2.7/site-packages/django/core/handlers/base.py" in get_response
  112.                     response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/Users/sachinshukla/Desktop/gmail/customer_support/views.py" in index
  70.       credentials = run(flow, storage, http=http)
File "/Library/Python/2.7/site-packages/oauth2client/util.py" in positional_wrapper
  132.       return wrapped(*args, **kwargs)
File "/Library/Python/2.7/site-packages/oauth2client/old_run.py" in run
  156.   storage.put(credential)
File "/Library/Python/2.7/site-packages/oauth2client/client.py" in put
  325.       self.locked_put(credentials)
File "/Library/Python/2.7/site-packages/oauth2client/django_orm.py" in locked_put
  126.     entity = self.model_class(**args)
File "/Library/Python/2.7/site-packages/django/db/models/base.py" in __init__
  405.                 setattr(self, field.name, rel_obj)
File "/Library/Python/2.7/site-packages/django/db/models/fields/related.py" in __set__
  335.                                 (instance._meta.object_name, self.field.name))

Exception Type: ValueError at /customer_support/
Exception Value: Cannot assign None: "CredentialsModel.id" does not allow null values.

ビューのコード:

CLIENT_SECRETS = os.path.join(os.path.dirname(__file__), '..', 'client_secret.json')
REDIRECT_URI = 'http://localhost:8080/'
SCOPES = [
'https://www.googleapis.com/auth/gmail.modify',
]


def index(request):
    storage = Storage(CredentialsModel, 'id', request.user.id, 'credential')
    credentials = storage.get()

    flow = flow_from_clientsecrets(CLIENT_SECRETS, scope=SCOPES)
    http = httplib2.Http()

    if credentials is None or credentials.invalid:
        credentials = run(flow, storage, http=http)

    # Authorize the httplib2.Http object with our credentials
    http = credentials.authorize(http)

    # Build the Gmail service from discovery
    gmail_service = build('gmail', 'v1', http=http)

    # then do something, query threads, messages, etc, 
    and return them to a template - not sure where exactly to put the methods for querying     threads, messages, etc.

モデル：

from django.db import models

import pickle
import base64

from django.contrib import admin
from django.contrib.auth.models import User
from django.db import models

from oauth2client.django_orm import FlowField
from oauth2client.django_orm import CredentialsField


class CredentialsModel(models.Model):
  id = models.ForeignKey(User, primary_key=True)
  credential = CredentialsField()


class CredentialsAdmin(admin.ModelAdmin):
  pass


admin.site.register(CredentialsModel, CredentialsAdmin)