def __init__(self):
"""Construct the backend instance by initializing all the collections."""
self._authinfos = authinfos.DjangoAuthInfoCollection(self)
self._comments = comments.DjangoCommentCollection(self)
self._computers = computers.DjangoComputerCollection(self)
self._groups = groups.DjangoGroupCollection(self)
self._logs = logs.DjangoLogCollection(self)
self._nodes = nodes.DjangoNodeCollection(self)
self._query_manager = DjangoQueryManager(self)
self._backend_manager = DjangoBackendManager()
self._users = users.DjangoUserCollection(self)
def get_backend_manager(backend):
"""Get an instance of the `BackendManager` for the current backend.
:param backend: the type of the database backend
:return: `BackendManager`
"""
if backend == BACKEND_DJANGO:
from aiida.backends.djsite.manager import DjangoBackendManager
return DjangoBackendManager()
if backend == BACKEND_SQLA:
from aiida.backends.sqlalchemy.manager import SqlaBackendManager
return SqlaBackendManager()
raise Exception(f'unknown backend type `{backend}`')
class DjangoBackend(SqlBackend[models.Model]):
"""Django implementation of `aiida.orm.implementation.backends.Backend`."""
def __init__(self):
"""Construct the backend instance by initializing all the collections."""
self._authinfos = authinfos.DjangoAuthInfoCollection(self)
self._comments = comments.DjangoCommentCollection(self)
self._computers = computers.DjangoComputerCollection(self)
self._groups = groups.DjangoGroupCollection(self)
self._logs = logs.DjangoLogCollection(self)
self._nodes = nodes.DjangoNodeCollection(self)
self._query_manager = DjangoQueryManager(self)
self._backend_manager = DjangoBackendManager()
self._users = users.DjangoUserCollection(self)
def migrate(self):
self._backend_manager.migrate()
@property
def authinfos(self):
return self._authinfos
@property
def comments(self):
return self._comments
@property
def computers(self):
return self._computers
@property
def groups(self):
return self._groups
@property
def logs(self):
return self._logs
@property
def nodes(self):
return self._nodes
@property
def query_manager(self):
return self._query_manager
def query(self):
return querybuilder.DjangoQueryBuilder(self)
@property
def users(self):
return self._users
@staticmethod
def transaction():
"""Open a transaction to be used as a context manager."""
return transaction.atomic()
# Below are abstract methods inherited from `aiida.orm.implementation.sql.backends.SqlBackend`
def get_backend_entity(self, model):
"""Return a `BackendEntity` instance from a `DbModel` instance."""
return convert.get_backend_entity(model, self)
@contextmanager
def cursor(self):
"""Return a psycopg cursor to be used in a context manager.
:return: a psycopg cursor
:rtype: :class:`psycopg2.extensions.cursor`
"""
try:
yield self.get_connection().cursor()
finally:
pass
def execute_raw(self, query):
"""Execute a raw SQL statement and return the result.
:param query: a string containing a raw SQL statement
:return: the result of the query
"""
with self.cursor() as cursor:
cursor.execute(query)
results = cursor.fetchall()
return results
@staticmethod
def get_connection():
"""
Get the Django connection
:return: the django connection
"""
# pylint: disable=import-error,no-name-in-module
from django.db import connection
# For now we just return the global but if we ever support multiple Django backends
# being loaded this should be specific to this backend
return connection