124 lines
4.7 KiB
Python
124 lines
4.7 KiB
Python
import uuid
|
|
from datetime import datetime
|
|
from typing import Set
|
|
|
|
from flask import g
|
|
from sqlalchemy.dialects.postgresql import UUID
|
|
from sqlalchemy.sql import expression
|
|
from sqlalchemy_utils import LtreeType
|
|
from sqlalchemy_utils.types.ltree import LQUERY
|
|
|
|
from ereuse_devicehub.db import db
|
|
from ereuse_devicehub.resources.device.models import Device
|
|
from ereuse_devicehub.resources.models import STR_SIZE, Thing
|
|
from ereuse_devicehub.resources.user.models import User
|
|
from teal.db import UUIDLtree
|
|
|
|
|
|
class Lot(Thing):
|
|
id = db.Column(UUID(as_uuid=True), primary_key=True) # uuid is generated on init by default
|
|
name = db.Column(db.Unicode(STR_SIZE), nullable=False)
|
|
closed = db.Column(db.Boolean, default=False, nullable=False)
|
|
closed.comment = """
|
|
A closed lot cannot be modified anymore.
|
|
"""
|
|
devices = db.relationship(Device,
|
|
backref=db.backref('parents', lazy=True, collection_class=set),
|
|
secondary=lambda: LotDevice.__table__,
|
|
collection_class=set)
|
|
|
|
def __init__(self, name: str, closed: bool = closed.default.arg) -> None:
|
|
"""
|
|
Initializes a lot
|
|
:param name:
|
|
:param closed:
|
|
"""
|
|
super().__init__(id=uuid.uuid4(), name=name, closed=closed)
|
|
Edge(self) # Lots have always one edge per default.
|
|
|
|
def add_child(self, child: 'Lot'):
|
|
"""Adds a child to this lot."""
|
|
Edge.add(self.id, child.id)
|
|
db.session.refresh(self) # todo is this useful?
|
|
db.session.refresh(child)
|
|
|
|
def remove_child(self, child: 'Lot'):
|
|
Edge.delete(self.id, child.id)
|
|
|
|
def __contains__(self, child: 'Lot'):
|
|
return Edge.has_lot(self.id, child.id)
|
|
|
|
@classmethod
|
|
def roots(cls):
|
|
"""Gets the lots that are not under any other lot."""
|
|
return set(cls.query.join(cls.edges).filter(db.func.nlevel(Edge.path) == 1).all())
|
|
|
|
def __repr__(self) -> str:
|
|
return '<Lot {0.name} devices={0.devices!r}>'.format(self)
|
|
|
|
|
|
class LotDevice(db.Model):
|
|
device_id = db.Column(db.BigInteger, db.ForeignKey(Device.id), primary_key=True)
|
|
lot_id = db.Column(UUID(as_uuid=True), db.ForeignKey(Lot.id), primary_key=True)
|
|
created = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
|
|
author_id = db.Column(UUID(as_uuid=True),
|
|
db.ForeignKey(User.id),
|
|
nullable=False,
|
|
default=lambda: g.user.id)
|
|
author = db.relationship(User, primaryjoin=author_id == User.id)
|
|
author_id.comment = """
|
|
The user that put the device in the lot.
|
|
"""
|
|
|
|
|
|
class Edge(db.Model):
|
|
id = db.Column(db.UUID(as_uuid=True),
|
|
primary_key=True,
|
|
server_default=db.text('gen_random_uuid()'))
|
|
lot_id = db.Column(db.UUID(as_uuid=True), db.ForeignKey(Lot.id), nullable=False)
|
|
lot = db.relationship(Lot,
|
|
backref=db.backref('edges', lazy=True, collection_class=set),
|
|
primaryjoin=Lot.id == lot_id)
|
|
path = db.Column(LtreeType, nullable=False)
|
|
created = db.Column(db.TIMESTAMP(timezone=True), server_default=db.text('CURRENT_TIMESTAMP'))
|
|
created.comment = """
|
|
When Devicehub created this.
|
|
"""
|
|
|
|
__table_args__ = (
|
|
db.UniqueConstraint(path, name='edge_path_unique', deferrable=True, initially='immediate'),
|
|
db.Index('path_gist', path, postgresql_using='gist'),
|
|
db.Index('path_btree', path, postgresql_using='btree')
|
|
)
|
|
|
|
def __init__(self, lot: Lot) -> None:
|
|
super().__init__(lot=lot)
|
|
self.path = UUIDLtree(lot.id)
|
|
|
|
def children(self) -> Set['Edge']:
|
|
"""Get the children edges."""
|
|
# todo is it useful? test it when first usage
|
|
# From https://stackoverflow.com/a/41158890
|
|
exp = '*.{}.*{{1}}'.format(self.lot_id)
|
|
return set(self.query
|
|
.filter(self.path.lquery(expression.cast(exp, LQUERY)))
|
|
.distinct(self.__class__.lot_id)
|
|
.all())
|
|
|
|
@classmethod
|
|
def add(cls, parent_id: uuid.UUID, child_id: uuid.UUID):
|
|
"""Creates an edge between parent and child."""
|
|
db.session.execute(db.func.add_edge(str(parent_id), str(child_id)))
|
|
|
|
@classmethod
|
|
def delete(cls, parent_id: uuid.UUID, child_id: uuid.UUID):
|
|
"""Deletes the edge between parent and child."""
|
|
db.session.execute(db.func.delete_edge(str(parent_id), str(child_id)))
|
|
|
|
@classmethod
|
|
def has_lot(cls, parent_id: uuid.UUID, child_id: uuid.UUID) -> bool:
|
|
return bool(db.session.execute(
|
|
"SELECT 1 from edge where path ~ '*.{}.*.{}.*'".format(
|
|
str(parent_id).replace('-', '_'), str(child_id).replace('-', '_'))
|
|
).first())
|