| # Copyright 2016 Google Inc. All rights reserved. |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); |
| # you may not use this file except in compliance with the License. |
| # You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| |
| """Contains classes used for the Django ORM storage.""" |
| |
| import base64 |
| import pickle |
| |
| from django.db import models |
| from django.utils import encoding |
| |
| import oauth2client |
| |
| |
| class CredentialsField(models.Field): |
| """Django ORM field for storing OAuth2 Credentials.""" |
| |
| def __init__(self, *args, **kwargs): |
| if 'null' not in kwargs: |
| kwargs['null'] = True |
| super(CredentialsField, self).__init__(*args, **kwargs) |
| |
| def get_internal_type(self): |
| return 'BinaryField' |
| |
| def from_db_value(self, value, expression, connection, context): |
| """Overrides ``models.Field`` method. This converts the value |
| returned from the database to an instance of this class. |
| """ |
| return self.to_python(value) |
| |
| def to_python(self, value): |
| """Overrides ``models.Field`` method. This is used to convert |
| bytes (from serialization etc) to an instance of this class""" |
| if value is None: |
| return None |
| elif isinstance(value, oauth2client.client.Credentials): |
| return value |
| else: |
| return pickle.loads(base64.b64decode(encoding.smart_bytes(value))) |
| |
| def get_prep_value(self, value): |
| """Overrides ``models.Field`` method. This is used to convert |
| the value from an instances of this class to bytes that can be |
| inserted into the database. |
| """ |
| if value is None: |
| return None |
| else: |
| return encoding.smart_text(base64.b64encode(pickle.dumps(value))) |
| |
| def value_to_string(self, obj): |
| """Convert the field value from the provided model to a string. |
| |
| Used during model serialization. |
| |
| Args: |
| obj: db.Model, model object |
| |
| Returns: |
| string, the serialized field value |
| """ |
| value = self._get_val_from_obj(obj) |
| return self.get_prep_value(value) |