etesync-server/django_etebase/models.py
2020-12-14 16:47:47 +02:00

248 lines
8.7 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/>.
from pathlib import Path
from django.db import models, transaction
from django.conf import settings
from django.core.validators import RegexValidator
from django.db.models import Max, Value as V
from django.db.models.functions import Coalesce, Greatest
from django.utils.functional import cached_property
from django.utils.crypto import get_random_string
from . import app_settings
UidValidator = RegexValidator(regex=r"^[a-zA-Z0-9\-_]{20,}$", message="Not a valid UID")
def stoken_annotation_builder(stoken_id_fields):
aggr_fields = [Coalesce(Max(field), V(0)) for field in stoken_id_fields]
return Greatest(*aggr_fields) if len(aggr_fields) > 1 else aggr_fields[0]
class CollectionType(models.Model):
owner = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
uid = models.BinaryField(editable=True, blank=False, null=False, db_index=True, unique=True)
class Collection(models.Model):
main_item = models.OneToOneField("CollectionItem", related_name="parent", null=True, on_delete=models.SET_NULL)
# The same as main_item.uid, we just also save it here so we have DB constraints for uniqueness (and efficiency)
uid = models.CharField(db_index=True, unique=True, blank=False, max_length=43, validators=[UidValidator])
owner = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
stoken_annotation = stoken_annotation_builder(["items__revisions__stoken", "members__stoken"])
def __str__(self):
return self.uid
@property
def content(self):
return self.main_item.content
@property
def etag(self):
return self.content.uid
@cached_property
def stoken(self):
stoken_id = (
self.__class__.objects.filter(main_item=self.main_item)
.annotate(max_stoken=self.stoken_annotation)
.values("max_stoken")
.first()["max_stoken"]
)
if stoken_id == 0:
raise Exception("stoken is None. Should never happen")
return Stoken.objects.get(id=stoken_id).uid
class CollectionItem(models.Model):
uid = models.CharField(db_index=True, blank=False, max_length=43, validators=[UidValidator])
collection = models.ForeignKey(Collection, related_name="items", on_delete=models.CASCADE)
version = models.PositiveSmallIntegerField()
encryptionKey = models.BinaryField(editable=True, blank=False, null=True)
stoken_annotation = stoken_annotation_builder(["revisions__stoken"])
class Meta:
unique_together = ("uid", "collection")
def __str__(self):
return "{} {}".format(self.uid, self.collection.uid)
@cached_property
def content(self):
return self.revisions.get(current=True)
@property
def etag(self):
return self.content.uid
def chunk_directory_path(instance, filename):
custom_func = app_settings.CHUNK_PATH_FUNC
if custom_func is not None:
return custom_func(instance, filename)
col = instance.collection
user_id = col.owner.id
uid_prefix = instance.uid[:2]
uid_rest = instance.uid[2:]
return Path("user_{}".format(user_id), col.uid, uid_prefix, uid_rest)
class CollectionItemChunk(models.Model):
uid = models.CharField(db_index=True, blank=False, null=False, max_length=60, validators=[UidValidator])
collection = models.ForeignKey(Collection, related_name="chunks", on_delete=models.CASCADE)
chunkFile = models.FileField(upload_to=chunk_directory_path, max_length=150, unique=True)
def __str__(self):
return self.uid
class Meta:
unique_together = ("collection", "uid")
def generate_stoken_uid():
return get_random_string(32, allowed_chars="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-_")
class Stoken(models.Model):
uid = models.CharField(
db_index=True,
unique=True,
blank=False,
null=False,
default=generate_stoken_uid,
max_length=43,
validators=[UidValidator],
)
class CollectionItemRevision(models.Model):
stoken = models.OneToOneField(Stoken, on_delete=models.PROTECT)
uid = models.CharField(
db_index=True, unique=True, blank=False, null=False, max_length=43, validators=[UidValidator]
)
item = models.ForeignKey(CollectionItem, related_name="revisions", on_delete=models.CASCADE)
meta = models.BinaryField(editable=True, blank=False, null=False)
current = models.BooleanField(db_index=True, default=True, null=True)
deleted = models.BooleanField(default=False)
class Meta:
unique_together = ("item", "current")
def __str__(self):
return "{} {} current={}".format(self.uid, self.item.uid, self.current)
class RevisionChunkRelation(models.Model):
chunk = models.ForeignKey(CollectionItemChunk, related_name="revisions_relation", on_delete=models.CASCADE)
revision = models.ForeignKey(CollectionItemRevision, related_name="chunks_relation", on_delete=models.CASCADE)
class Meta:
ordering = ("id",)
class AccessLevels(models.IntegerChoices):
READ_ONLY = 0
ADMIN = 1
READ_WRITE = 2
class CollectionMember(models.Model):
stoken = models.OneToOneField(Stoken, on_delete=models.PROTECT, null=True)
collection = models.ForeignKey(Collection, related_name="members", on_delete=models.CASCADE)
user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
encryptionKey = models.BinaryField(editable=True, blank=False, null=False)
collectionType = models.ForeignKey(CollectionType, on_delete=models.PROTECT, null=True)
accessLevel = models.IntegerField(
choices=AccessLevels.choices,
default=AccessLevels.READ_ONLY,
)
stoken_annotation = stoken_annotation_builder(["stoken"])
class Meta:
unique_together = ("user", "collection")
def __str__(self):
return "{} {}".format(self.collection.uid, self.user)
def revoke(self):
with transaction.atomic():
CollectionMemberRemoved.objects.update_or_create(
collection=self.collection,
user=self.user,
defaults={
"stoken": Stoken.objects.create(),
},
)
self.delete()
class CollectionMemberRemoved(models.Model):
stoken = models.OneToOneField(Stoken, on_delete=models.PROTECT, null=True)
collection = models.ForeignKey(Collection, related_name="removed_members", on_delete=models.CASCADE)
user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
class Meta:
unique_together = ("user", "collection")
def __str__(self):
return "{} {}".format(self.collection.uid, self.user)
class CollectionInvitation(models.Model):
uid = models.CharField(db_index=True, blank=False, null=False, max_length=43, validators=[UidValidator])
version = models.PositiveSmallIntegerField(default=1)
fromMember = models.ForeignKey(CollectionMember, on_delete=models.CASCADE)
# FIXME: make sure to delete all invitations for the same collection once one is accepted
# Make sure to not allow invitations if already a member
user = models.ForeignKey(settings.AUTH_USER_MODEL, related_name="incoming_invitations", on_delete=models.CASCADE)
signedEncryptionKey = models.BinaryField(editable=False, blank=False, null=False)
accessLevel = models.IntegerField(
choices=AccessLevels.choices,
default=AccessLevels.READ_ONLY,
)
class Meta:
unique_together = ("user", "fromMember")
def __str__(self):
return "{} {}".format(self.fromMember.collection.uid, self.user)
@cached_property
def collection(self):
return self.fromMember.collection
class UserInfo(models.Model):
owner = models.OneToOneField(settings.AUTH_USER_MODEL, on_delete=models.CASCADE, primary_key=True)
version = models.PositiveSmallIntegerField(default=1)
loginPubkey = models.BinaryField(editable=True, blank=False, null=False)
pubkey = models.BinaryField(editable=True, blank=False, null=False)
encryptedContent = models.BinaryField(editable=True, blank=False, null=False)
salt = models.BinaryField(editable=True, blank=False, null=False)
def __str__(self):
return "UserInfo<{}>".format(self.owner)