An implementation of repository pattern for SQLAlchemy.
install by pip:
$ pip install rebecca.repositoryImplement your model by SQLAlchemy:
from sqlalchemy import Column, Integer, Unicode
from sqlalchemy.ext.declarative import declarative_base
Base = declarative_base()
DBSession = scoped_session(sessionmaker())
class Person(Base):
__tablename__ = "person"
id = Column(Integer, primary_key=True)
name = Column(Unicode(255))
age = Column(Integer, default=0)
job = Column(Unicode(255))Get repository:
from rebecca.repository.sqla import SQLARepository
person_repository = SQALRepository(Person, Person.id, DBSession())this repository for Person model. To get person, use Person.id as key.
repository can configure to set condition:
person_repository = SQALRepository(Person, Person.id, DBSession(), condition=Person.age>30)If you pass the parameters during request time, use factory.
class JobPersonRepository(SQLARepository):
def __init__(self, db_session, job):
super(JobPersonRepository, self).__init__(Person, Person.id, dbsession,
condition=Person.job==job)The parameter job will be passed from request attribute.
To register repository factory, add_repository_factory directive:
config.add_repository_factory(JobPersonRepository, "job-person", args=(DBSession,))or repository_factory_config decorator:
@repository_factory_config("job-person", args=(DBSession,))
class JobPersonRepository(SQLARepository):
....To create repository from registered factory, call create_repository API:
job = request.matchdict["job"]
repository = create_repository("person", args=(job,))rebecca.repository.fs.FileSystemRepository is repository for FileSystem:
>>> repository = FileSystemRepository(directory="/path/to/data")
>>> item = repository.new_item("new-item")
>>> item.data = b"testing-binary-data"
>>> import transaction
>>> transaction.commit()FileSystemRepository.new_item is create new file system entry. item.data is binary data that saved in the file. That's transactional with transaction .
Note
FileSystemRepository uses repoze.filesafe that not supports py3k yet.
create object for demonstration:
person1 = Person(name=u"person1")
DBSession.add(person1)
DBSession.flush() # to generate person.idA repository has dict like interface:
person_repository[person.id]
person_repository.get(person.id)and utility methods:
person_repository.get_many([1, 2, 3])
new_person = person_repository.new_item()rebecca.repository provides directive for pyramid registry.:
config.include('rebecca.repository')
config.add_repository(person_repository, 'person')or using repository_config decorator:
@repository_config(name="person", args=(DBSession,))
class PersonRepository(SQLARepository):
def __init__(self, dbsession):
super(PersonRepository, self).__init__(Person, Person.id, dbsession)To get registered repositories, use get_repository:
get_repository(request, 'person')