etesync-server/django_etesync/serializers.py
Tom Hacohen 9c63f8d674 Rename stoken to etag and cstoken to stoken.
This conforms better with what people know from HTTP and properly
differentiates from CSToken which is now renamed to stoken.
2020-05-27 10:30:22 +03:00

416 lines
14 KiB
Python

# Copyright © 2017 Tom Hacohen
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, version 3.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import base64
from django.core.files.base import ContentFile
from django.contrib.auth import get_user_model
from django.db import transaction
from rest_framework import serializers
from . import models
User = get_user_model()
def process_revisions_for_item(item, revision_data):
chunks_objs = []
chunks = revision_data.pop('chunks_relation')
for chunk in chunks:
uid = chunk[0]
if len(chunk) > 1:
content = chunk[1]
chunk = models.CollectionItemChunk(uid=uid, item=item)
chunk.chunkFile.save('IGNORED', ContentFile(content))
chunk.save()
chunks_objs.append(chunk)
else:
chunk = models.CollectionItemChunk.objects.get(uid=uid)
chunks_objs.append(chunk)
stoken = models.Stoken.objects.create()
revision = models.CollectionItemRevision.objects.create(**revision_data, item=item, stoken=stoken)
for chunk in chunks_objs:
models.RevisionChunkRelation.objects.create(chunk=chunk, revision=revision)
return revision
def b64encode(value):
return base64.urlsafe_b64encode(value).decode('ascii').strip('=')
def b64decode(data):
data += "=" * ((4 - len(data) % 4) % 4)
return base64.urlsafe_b64decode(data)
class BinaryBase64Field(serializers.Field):
def to_representation(self, value):
return b64encode(value)
def to_internal_value(self, data):
return b64decode(data)
class CollectionEncryptionKeyField(BinaryBase64Field):
def get_attribute(self, instance):
request = self.context.get('request', None)
if request is not None:
return instance.members.get(user=request.user).encryptionKey
return None
class CollectionContentField(BinaryBase64Field):
def get_attribute(self, instance):
request = self.context.get('request', None)
if request is not None:
return instance.members.get(user=request.user).encryptionKey
return None
class ChunksField(serializers.RelatedField):
def to_representation(self, obj):
obj = obj.chunk
inline = self.context.get('inline', False)
if inline:
with open(obj.chunkFile.path, 'rb') as f:
return (obj.uid, b64encode(f.read()))
else:
return (obj.uid, )
def to_internal_value(self, data):
return (data[0], b64decode(data[1]))
class CollectionItemChunkSerializer(serializers.ModelSerializer):
class Meta:
model = models.CollectionItemChunk
fields = ('uid', 'chunkFile')
class CollectionItemRevisionSerializer(serializers.ModelSerializer):
chunks = ChunksField(
source='chunks_relation',
queryset=models.RevisionChunkRelation.objects.all(),
many=True
)
meta = BinaryBase64Field()
class Meta:
model = models.CollectionItemRevision
fields = ('chunks', 'meta', 'uid', 'deleted')
class CollectionItemSerializer(serializers.ModelSerializer):
encryptionKey = BinaryBase64Field()
etag = serializers.CharField(allow_null=True)
content = CollectionItemRevisionSerializer(many=False)
class Meta:
model = models.CollectionItem
fields = ('uid', 'version', 'encryptionKey', 'content', 'etag')
def create(self, validated_data):
"""Function that's called when this serializer creates an item"""
validate_etag = self.context.get('validate_etag', False)
etag = validated_data.pop('etag')
revision_data = validated_data.pop('content')
uid = validated_data.pop('uid')
Model = self.__class__.Meta.model
with transaction.atomic():
instance, created = Model.objects.get_or_create(uid=uid, defaults=validated_data)
cur_etag = instance.etag if not created else None
if validate_etag and cur_etag != etag:
raise serializers.ValidationError('Wrong etag. Expected {} got {}'.format(cur_etag, etag))
if not created:
# We don't have to use select_for_update here because the unique constraint on current guards against
# the race condition. But it's a good idea because it'll lock and wait rather than fail.
current_revision = instance.revisions.filter(current=True).select_for_update().first()
current_revision.current = None
current_revision.save()
process_revisions_for_item(instance, revision_data)
return instance
def update(self, instance, validated_data):
# We never update, we always update in the create method
raise NotImplementedError()
class CollectionItemDepSerializer(serializers.ModelSerializer):
etag = serializers.CharField()
class Meta:
model = models.CollectionItem
fields = ('uid', 'etag')
def validate(self, data):
item = self.__class__.Meta.model.objects.get(uid=data['uid'])
etag = data['etag']
if item.etag != etag:
raise serializers.ValidationError('Wrong etag. Expected {} got {}'.format(item.etag, etag))
return data
class CollectionItemBulkGetSerializer(serializers.ModelSerializer):
etag = serializers.CharField(required=False)
class Meta:
model = models.CollectionItem
fields = ('uid', 'etag')
class CollectionSerializer(serializers.ModelSerializer):
encryptionKey = CollectionEncryptionKeyField()
accessLevel = serializers.SerializerMethodField('get_access_level_from_context')
stoken = serializers.CharField(read_only=True)
etag = serializers.CharField(allow_null=True)
content = CollectionItemRevisionSerializer(many=False)
class Meta:
model = models.Collection
fields = ('uid', 'version', 'accessLevel', 'encryptionKey', 'content', 'stoken', 'etag')
def get_access_level_from_context(self, obj):
request = self.context.get('request', None)
if request is not None:
return obj.members.get(user=request.user).accessLevel
return None
def create(self, validated_data):
"""Function that's called when this serializer creates an item"""
etag = validated_data.pop('etag')
revision_data = validated_data.pop('content')
encryption_key = validated_data.pop('encryptionKey')
instance = self.__class__.Meta.model(**validated_data)
with transaction.atomic():
if etag is not None:
raise serializers.ValidationError('Stoken is not None')
instance.save()
main_item = models.CollectionItem.objects.create(
uid=None, encryptionKey=None, version=instance.version, collection=instance)
process_revisions_for_item(main_item, revision_data)
models.CollectionMember(collection=instance,
user=validated_data.get('owner'),
accessLevel=models.AccessLevels.ADMIN,
encryptionKey=encryption_key,
).save()
return instance
def update(self, instance, validated_data):
"""Function that's called when this serializer is meant to update an item"""
etag = validated_data.pop('etag')
revision_data = validated_data.pop('content')
with transaction.atomic():
if etag != instance.etag:
raise serializers.ValidationError('Wrong etag. Expected {} got {}'.format(instance.etag, etag))
main_item = instance.main_item
# We don't have to use select_for_update here because the unique constraint on current guards against
# the race condition. But it's a good idea because it'll lock and wait rather than fail.
current_revision = main_item.revisions.filter(current=True).select_for_update().first()
current_revision.current = None
current_revision.save()
process_revisions_for_item(main_item, revision_data)
return instance
class CollectionMemberSerializer(serializers.ModelSerializer):
username = serializers.SlugRelatedField(
source='user',
slug_field=User.USERNAME_FIELD,
queryset=User.objects
)
encryptionKey = BinaryBase64Field()
class Meta:
model = models.CollectionMember
fields = ('username', 'encryptionKey', 'accessLevel')
def create(self, validated_data):
raise NotImplementedError()
def update(self, instance, validated_data):
with transaction.atomic():
# We only allow updating accessLevel
instance.accessLevel = validated_data.pop('accessLevel')
instance.save()
return instance
class CollectionInvitationSerializer(serializers.ModelSerializer):
username = serializers.SlugRelatedField(
source='user',
slug_field=User.USERNAME_FIELD,
queryset=User.objects
)
collection = serializers.CharField(source='collection.uid')
fromPubkey = BinaryBase64Field(source='fromMember.user.userinfo.pubkey', read_only=True)
signedEncryptionKey = BinaryBase64Field()
class Meta:
model = models.CollectionInvitation
fields = ('username', 'uid', 'collection', 'signedEncryptionKey', 'accessLevel', 'fromPubkey', 'version')
def validate_user(self, value):
request = self.context['request']
if request.user == value.lower():
raise serializers.ValidationError('Inviting yourself is not allowed')
return value
def create(self, validated_data):
request = self.context['request']
collection = validated_data.pop('collection')
member = collection.members.get(user=request.user)
with transaction.atomic():
return type(self).Meta.model.objects.create(**validated_data, fromMember=member)
def update(self, instance, validated_data):
with transaction.atomic():
instance.accessLevel = validated_data.pop('accessLevel')
instance.signedEncryptionKey = validated_data.pop('signedEncryptionKey')
instance.save()
return instance
class InvitationAcceptSerializer(serializers.Serializer):
encryptionKey = BinaryBase64Field()
def create(self, validated_data):
with transaction.atomic():
invitation = self.context['invitation']
encryption_key = validated_data.get('encryptionKey')
member = models.CollectionMember.objects.create(
collection=invitation.collection,
user=invitation.user,
accessLevel=invitation.accessLevel,
encryptionKey=encryption_key,
)
invitation.delete()
return member
def update(self, instance, validated_data):
raise NotImplementedError()
class UserSerializer(serializers.ModelSerializer):
pubkey = BinaryBase64Field(source='userinfo.pubkey')
encryptedSeckey = BinaryBase64Field(source='userinfo.encryptedSeckey')
class Meta:
model = User
fields = (User.USERNAME_FIELD, User.EMAIL_FIELD, 'pubkey', 'encryptedSeckey')
class UserQuerySerializer(serializers.ModelSerializer):
class Meta:
model = User
fields = (User.USERNAME_FIELD, User.EMAIL_FIELD)
class UserInfoPubkeySerializer(serializers.ModelSerializer):
pubkey = BinaryBase64Field()
class Meta:
model = models.UserInfo
fields = ('pubkey', )
class AuthenticationSignupSerializer(serializers.Serializer):
user = UserQuerySerializer(many=False)
salt = BinaryBase64Field()
loginPubkey = BinaryBase64Field()
pubkey = BinaryBase64Field()
encryptedSeckey = BinaryBase64Field()
def create(self, validated_data):
"""Function that's called when this serializer creates an item"""
user_data = validated_data.pop('user')
with transaction.atomic():
instance, _ = User.objects.get_or_create(**user_data)
if hasattr(instance, 'userinfo'):
raise serializers.ValidationError('User already exists')
instance.set_unusable_password()
# FIXME: send email verification
models.UserInfo.objects.create(**validated_data, owner=instance)
return instance
def update(self, instance, validated_data):
raise NotImplementedError()
class AuthenticationLoginChallengeSerializer(serializers.Serializer):
username = serializers.CharField(required=False)
email = serializers.EmailField(required=False)
def validate(self, data):
if not data.get('email') and not data.get('username'):
raise serializers.ValidationError('Either email or username must be set')
return data
def create(self, validated_data):
raise NotImplementedError()
def update(self, instance, validated_data):
raise NotImplementedError()
class AuthenticationLoginSerializer(serializers.Serializer):
response = BinaryBase64Field()
signature = BinaryBase64Field()
def create(self, validated_data):
raise NotImplementedError()
def update(self, instance, validated_data):
raise NotImplementedError()
class AuthenticationLoginInnerSerializer(AuthenticationLoginChallengeSerializer):
challenge = BinaryBase64Field()
host = serializers.CharField()
def create(self, validated_data):
raise NotImplementedError()
def update(self, instance, validated_data):
raise NotImplementedError()