mirror of
https://github.com/sqlalchemy/sqlalchemy.git
synced 2026-05-10 02:39:59 -04:00
Mike Bayer
106 lines
3.0 KiB
Python
106 lines
3.0 KiB
Python
"""Model. We are modeling Person objects with a collection
|
|
of Address objects. Each Address has a PostalCode, which
|
|
in turn references a City and then a Country:
|
|
|
|
Person --(1..n)--> Address
|
|
Address --(has a)--> PostalCode
|
|
PostalCode --(has a)--> City
|
|
City --(has a)--> Country
|
|
|
|
"""
|
|
from sqlalchemy import Column, Integer, String, ForeignKey
|
|
from sqlalchemy.orm import relationship
|
|
from caching_query import FromCache, RelationshipCache
|
|
from environment import Base, bootstrap
|
|
|
|
class Country(Base):
|
|
__tablename__ = 'country'
|
|
|
|
id = Column(Integer, primary_key=True)
|
|
name = Column(String(100), nullable=False)
|
|
|
|
def __init__(self, name):
|
|
self.name = name
|
|
|
|
class City(Base):
|
|
__tablename__ = 'city'
|
|
|
|
id = Column(Integer, primary_key=True)
|
|
name = Column(String(100), nullable=False)
|
|
country_id = Column(Integer, ForeignKey('country.id'), nullable=False)
|
|
country = relationship(Country)
|
|
|
|
def __init__(self, name, country):
|
|
self.name = name
|
|
self.country = country
|
|
|
|
class PostalCode(Base):
|
|
__tablename__ = 'postal_code'
|
|
|
|
id = Column(Integer, primary_key=True)
|
|
code = Column(String(10), nullable=False)
|
|
city_id = Column(Integer, ForeignKey('city.id'), nullable=False)
|
|
city = relationship(City)
|
|
|
|
@property
|
|
def country(self):
|
|
return self.city.country
|
|
|
|
def __init__(self, code, city):
|
|
self.code = code
|
|
self.city = city
|
|
|
|
class Address(Base):
|
|
__tablename__ = 'address'
|
|
|
|
id = Column(Integer, primary_key=True)
|
|
person_id = Column(Integer, ForeignKey('person.id'), nullable=False)
|
|
street = Column(String(200), nullable=False)
|
|
postal_code_id = Column(Integer, ForeignKey('postal_code.id'))
|
|
postal_code = relationship(PostalCode)
|
|
|
|
@property
|
|
def city(self):
|
|
return self.postal_code.city
|
|
|
|
@property
|
|
def country(self):
|
|
return self.postal_code.country
|
|
|
|
def __str__(self):
|
|
return "%s\t"\
|
|
"%s, %s\t"\
|
|
"%s" % (self.street, self.city.name,
|
|
self.postal_code.code, self.country.name)
|
|
|
|
class Person(Base):
|
|
__tablename__ = 'person'
|
|
|
|
id = Column(Integer, primary_key=True)
|
|
name = Column(String(100), nullable=False)
|
|
addresses = relationship(Address, collection_class=set)
|
|
|
|
def __init__(self, name, *addresses):
|
|
self.name = name
|
|
self.addresses = set(addresses)
|
|
|
|
def __str__(self):
|
|
return self.name
|
|
|
|
def __repr__(self):
|
|
return "Person(name=%r)" % self.name
|
|
|
|
def format_full(self):
|
|
return "\t".join([str(x) for x in [self] + list(self.addresses)])
|
|
|
|
# Caching options. A set of three RelationshipCache options
|
|
# which can be applied to Query(), causing the "lazy load"
|
|
# of these attributes to be loaded from cache.
|
|
cache_address_bits = RelationshipCache("default", "byid", PostalCode.city).\
|
|
and_(
|
|
RelationshipCache("default", "byid", City.country)
|
|
).and_(
|
|
RelationshipCache("default", "byid", Address.postal_code)
|
|
)
|
|
|
|
bootstrap() |