def init_db(self, db_path):
<EOL>self.database = '<STR_LIT>' % db_path<EOL>self.storage = SREGISTRY_STORAGE<EOL>bot.debug("<STR_LIT>" % self.database)<EOL>self.engine = create_engine(self.database, convert_unicode=True)<EOL>self.session = scoped_session(sessionmaker(autocommit=False,<EOL>autoflush=False,<EOL>bind=self.engine))<EOL>Base.query = self.session.query_property()<EOL>Base.metadata.create_all(bind=self.engine)<EOL>self.Base = Base<EOL>
initialize the database, with the default database path or custom of

       the format sqlite:////scif/data/expfactory.db

    The custom path can be set with the environment variable SREGISTRY_DATABASE
    when a user creates the client, we must initialize this db
    the database should use the .singularity cache folder to cache
    layers and images, and .singularity/sregistry.db as a database