def open(filename, backend_name=None, backend_args=None):
"""Open an existing database and return it.
- `filename`: Name of the file containing the database.
- `backend_name`: (optional) Name of the backend to use if
auto-detection is not desired.
- `backend_args`: (optional) Arguments to pass to the backend.
"""
backend = new_backend(filename, backend_name, backend_args)
# Make sure the database already exists.
root = backend.get_root()
if 'SCHEVO' not in root:
backend.close()
raise DatabaseDoesNotExist(filename)
# Determine the version of the database.
schevo = root['SCHEVO']
format = schevo['format']
# Determine database class based on format number.
Database = format_dbclass[format]
# Create the Database instance.
db = Database(backend)
db._sync()
# Install icon support and finalize opening of database.
icon.install(db)
return db
def create(filename, backend_name, backend_args={},
schema_source=None, schema_version=None, initialize=True,
format=None, label=u'Schevo Database'):
"""Create a new database and return it.
- `filename`: Filename of the new database.
- `backend_name`: Name of the backend to use when creating the
database.
- `backend_args`: (optional) Arguments to pass to the backend.
- `schema_source`: (optional) Schema source code to synchronize
the new database with. If `None` is given, the database will
exist but will contain no extents.
- `schema_version`: (optional) Version of the schema being used to
create the database. If `None` is given, `1` is assumed.
- `initialize`: `True` (default) if the new database should be
populated with initial values defined in the schema.
- `format`: (optional) Internal structure format to use. If
`None` is given, the latest format will be used.
- `label`: (optional) The label to give the new database.
"""
backend = new_backend(filename, backend_name, backend_args)
# Make sure the database doesn't already exist.
root = backend.get_root()
if 'SCHEVO' in root:
backend.close()
raise DatabaseAlreadyExists(filename)
# Continue creating the new database.
Database = format_dbclass[format]
db = Database(backend)
db._sync(
schema_source=schema_source,
schema_version=schema_version,
initialize=initialize,
)
# Apply label.
relabel(db, label)
# Install icon support.
icon.install(db)
return db
def open(url, backend_args=None):
"""Open an existing database and return it.
- `url`: URL of the database to open.
- `backend_args`: (optional) Additional arguments to pass to the backend.
"""
backend = new_backend(url, backend_args)
# Make sure the database already exists.
root = backend.get_root()
if 'SCHEVO' not in root:
backend.close()
raise DatabaseDoesNotExist(url)
# Determine the version of the database.
schevo = root['SCHEVO']
format = schevo['format']
# Determine database class based on format number.
Database = format_dbclass[format]
# Create the Database instance.
db = Database(backend)
db._sync()
# Install icon support and finalize opening of database.
icon.install(db)
return db
