Source code for aiida.backends.sqlalchemy.utils

# -*- coding: utf-8 -*-
###########################################################################
# Copyright (c), The AiiDA team. All rights reserved.                     #
# This file is part of the AiiDA code.                                    #
#                                                                         #
# The code is hosted on GitHub at https://github.com/aiidateam/aiida_core #
# For further information on the license, see the LICENSE.txt file        #
# For further information please visit http://www.aiida.net               #
###########################################################################


try:
    import ultrajson as json
    from functools import partial

    # double_precision = 15, to replicate what PostgreSQL numerical type is
    # using
    json_dumps = partial(json.dumps, double_precision=15)
    json_loads = partial(json.loads, precise_float=True)
except ImportError:
    import json

    json_dumps = json.dumps
    json_loads = json.loads

import datetime

import re
from alembic import command
from alembic.config import Config
from alembic.runtime.environment import EnvironmentContext
from alembic.script import ScriptDirectory
from dateutil import parser
from sqlalchemy import create_engine
from sqlalchemy.orm import scoped_session
from sqlalchemy.orm import sessionmaker

from aiida.backends import sqlalchemy as sa, settings
from aiida.common.exceptions import ConfigurationError
from aiida.common.setup import (get_profile_config)

ALEMBIC_FILENAME = "alembic.ini"
ALEMBIC_REL_PATH = "migrations"


# def is_dbenv_loaded():
#     """
#     Return if the environment has already been loaded or not.
#     """
#     return sa.get_scoped_session() is not None

[docs]def recreate_after_fork(engine): """ :param engine: the engine that will be used by the sessionmaker Callback called after a fork. Not only disposes the engine, but also recreates a new scoped session to use independent sessions in the forked process. """ sa.engine.dispose() sa.scopedsessionclass = scoped_session(sessionmaker(bind=sa.engine, expire_on_commit=True))
[docs]def reset_session(config): """ :param config: the configuration of the profile from the configuration file Resets (global) engine and sessionmaker classes, to create a new one (or creates a new one from scratch if not already available) """ from multiprocessing.util import register_after_fork engine_url = ( "postgresql://{AIIDADB_USER}:{AIIDADB_PASS}@" "{AIIDADB_HOST}:{AIIDADB_PORT}/{AIIDADB_NAME}" ).format(**config) sa.engine = create_engine(engine_url, json_serializer=dumps_json, json_deserializer=loads_json) sa.scopedsessionclass = scoped_session(sessionmaker(bind=sa.engine, expire_on_commit=True)) register_after_fork(sa.engine, recreate_after_fork)
[docs]def load_dbenv(process=None, profile=None, connection=None): """ Load the database environment (SQLAlchemy) and perform some checks. :param process: the process that is calling this command ('verdi', or 'daemon') :param profile: the string with the profile to use. If not specified, use the default one specified in the AiiDA configuration file. """ _load_dbenv_noschemacheck(process=process, profile=profile) # Check schema version and the existence of the needed tables check_schema_version()
[docs]def _load_dbenv_noschemacheck(process=None, profile=None, connection=None): """ Load the SQLAlchemy database. """ config = get_profile_config(settings.AIIDADB_PROFILE) reset_session(config)
_aiida_autouser_cache = None
[docs]def get_automatic_user(): # global _aiida_autouser_cache # if _aiida_autouser_cache is not None: # return _aiida_autouser_cache from aiida.backends.sqlalchemy.models.user import DbUser from aiida.common.utils import get_configured_user_email email = get_configured_user_email() _aiida_autouser_cache = DbUser.query.filter(DbUser.email == email).first() if not _aiida_autouser_cache: raise ConfigurationError("No aiida user with email {}".format( email)) return _aiida_autouser_cache
[docs]def get_daemon_user(): """ Return the username (email) of the user that should run the daemon, or the default AiiDA user in case no explicit configuration is found in the DbSetting table. """ from aiida.backends.sqlalchemy.globalsettings import get_global_setting from aiida.common.setup import DEFAULT_AIIDA_USER try: return get_global_setting('daemon|user') except KeyError: return DEFAULT_AIIDA_USER
[docs]def set_daemon_user(user_email): """ Return the username (email) of the user that should run the daemon, or the default AiiDA user in case no explicit configuration is found in the DbSetting table. """ from aiida.backends.sqlalchemy.globalsettings import set_global_setting set_global_setting("daemon|user", user_email, description="The only user that is allowed to run the " "AiiDA daemon on this DB instance")
[docs]def dumps_json(d): """ Transforms all datetime object into isoformat and then returns the JSON """ def f(v): if isinstance(v, list): return [f(_) for _ in v] elif isinstance(v, dict): return dict((key, f(val)) for key, val in v.iteritems()) elif isinstance(v, datetime.datetime): return v.isoformat() return v return json_dumps(f(d))
date_reg = re.compile(r'^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\.\d+(\+\d{2}:\d{2})?$')
[docs]def loads_json(s): """ Loads the json and try to parse each basestring as a datetime object """ ret = json_loads(s) def f(d): if isinstance(d, list): for i, val in enumerate(d): d[i] = f(val) return d elif isinstance(d, dict): for k, v in d.iteritems(): d[k] = f(v) return d elif isinstance(d, basestring): if date_reg.match(d): try: return parser.parse(d) except (ValueError, TypeError): return d return d return d return f(ret)
# XXX the code here isn't different from the one use in Django. We may be able # to refactor it in some way
[docs]def install_tc(session): """ Install the transitive closure table with SqlAlchemy. """ links_table_name = "db_dblink" links_table_input_field = "input_id" links_table_output_field = "output_id" closure_table_name = "db_dbpath" closure_table_parent_field = "parent_id" closure_table_child_field = "child_id" session.execute(get_pg_tc(links_table_name, links_table_input_field, links_table_output_field, closure_table_name, closure_table_parent_field, closure_table_child_field))
[docs]def get_pg_tc(links_table_name, links_table_input_field, links_table_output_field, closure_table_name, closure_table_parent_field, closure_table_child_field): """ Return the transitive closure table template """ from string import Template pg_tc = Template(""" DROP TRIGGER IF EXISTS autoupdate_tc ON $links_table_name; DROP FUNCTION IF EXISTS update_tc(); CREATE OR REPLACE FUNCTION update_tc() RETURNS trigger AS $$BODY$$ DECLARE new_id INTEGER; old_id INTEGER; num_rows INTEGER; BEGIN IF tg_op = 'INSERT' THEN IF EXISTS ( SELECT Id FROM $closure_table_name WHERE $closure_table_parent_field = new.$links_table_input_field AND $closure_table_child_field = new.$links_table_output_field AND depth = 0 ) THEN RETURN null; END IF; IF new.$links_table_input_field = new.$links_table_output_field OR EXISTS ( SELECT id FROM $closure_table_name WHERE $closure_table_parent_field = new.$links_table_output_field AND $closure_table_child_field = new.$links_table_input_field ) THEN RETURN null; END IF; INSERT INTO $closure_table_name ( $closure_table_parent_field, $closure_table_child_field, depth) VALUES ( new.$links_table_input_field, new.$links_table_output_field, 0); new_id := lastval(); UPDATE $closure_table_name SET entry_edge_id = new_id , exit_edge_id = new_id , direct_edge_id = new_id WHERE id = new_id; INSERT INTO $closure_table_name ( entry_edge_id, direct_edge_id, exit_edge_id, $closure_table_parent_field, $closure_table_child_field, depth) SELECT id , new_id , new_id , $closure_table_parent_field , new.$links_table_output_field , depth + 1 FROM $closure_table_name WHERE $closure_table_child_field = new.$links_table_input_field; INSERT INTO $closure_table_name ( entry_edge_id, direct_edge_id, exit_edge_id, $closure_table_parent_field, $closure_table_child_field, depth) SELECT new_id , new_id , id , new.$links_table_input_field , $closure_table_child_field , depth + 1 FROM $closure_table_name WHERE $closure_table_parent_field = new.$links_table_output_field; INSERT INTO $closure_table_name ( entry_edge_id, direct_edge_id, exit_edge_id, $closure_table_parent_field, $closure_table_child_field, depth) SELECT A.id , new_id , B.id , A.$closure_table_parent_field , B.$closure_table_child_field , A.depth + B.depth + 2 FROM $closure_table_name A CROSS JOIN $closure_table_name B WHERE A.$closure_table_child_field = new.$links_table_input_field AND B.$closure_table_parent_field = new.$links_table_output_field; END IF; IF tg_op = 'DELETE' THEN IF NOT EXISTS( SELECT id FROM $closure_table_name WHERE $closure_table_parent_field = old.$links_table_input_field AND $closure_table_child_field = old.$links_table_output_field AND depth = 0 ) THEN RETURN NULL; END IF; CREATE TABLE PurgeList (Id int); INSERT INTO PurgeList SELECT id FROM $closure_table_name WHERE $closure_table_parent_field = old.$links_table_input_field AND $closure_table_child_field = old.$links_table_output_field AND depth = 0; WHILE (1 = 1) loop INSERT INTO PurgeList SELECT id FROM $closure_table_name WHERE depth > 0 AND ( entry_edge_id IN ( SELECT Id FROM PurgeList ) OR direct_edge_id IN ( SELECT Id FROM PurgeList ) OR exit_edge_id IN ( SELECT Id FROM PurgeList ) ) AND Id NOT IN (SELECT Id FROM PurgeList ); GET DIAGNOSTICS num_rows = ROW_COUNT; if (num_rows = 0) THEN EXIT; END IF; end loop; DELETE FROM $closure_table_name WHERE Id IN ( SELECT Id FROM PurgeList); DROP TABLE PurgeList; END IF; RETURN NULL; END $$BODY$$ LANGUAGE plpgsql VOLATILE COST 100; CREATE TRIGGER autoupdate_tc AFTER INSERT OR DELETE OR UPDATE ON $links_table_name FOR each ROW EXECUTE PROCEDURE update_tc(); """) return pg_tc.substitute(links_table_name=links_table_name, links_table_input_field=links_table_input_field, links_table_output_field=links_table_output_field, closure_table_name=closure_table_name, closure_table_parent_field=closure_table_parent_field, closure_table_child_field=closure_table_child_field)
[docs]def check_schema_version(force_migration=False, alembic_cfg=None): """ Check if the version stored in the database is the same of the version of the code. :note: if the DbSetting table does not exist, this function does not fail. The reason is to avoid to have problems before running the first migrate call. :note: if no version is found, the version is set to the version of the code. This is useful to have the code automatically set the DB version at the first code execution. :raise ConfigurationError: if the two schema versions do not match. Otherwise, just return. """ import sys from aiida.common.utils import query_yes_no from aiida.backends import sqlalchemy as sa from aiida.backends.settings import IN_DOC_MODE # Early exit if we compile the documentation since the schema # check is not needed and it creates problems with the sqlalchemy # migrations if IN_DOC_MODE: return # If an alembic configuration file is given then use that one. if alembic_cfg is None: alembic_cfg = get_alembic_conf() # Getting the version of the code and the database # Reusing the existing engine (initialized by AiiDA) with sa.engine.begin() as connection: alembic_cfg.attributes['connection'] = connection code_schema_version = get_migration_head(alembic_cfg) db_schema_version = get_db_schema_version(alembic_cfg) if code_schema_version != db_schema_version: if db_schema_version is None: print("It is time to perform your first SQLAlchemy migration.") else: print("The code schema version is {}, but the version stored in " "the database is {}." .format(code_schema_version, db_schema_version)) if force_migration or query_yes_no("Would you like to migrate to the " "latest version?", "yes"): print("Migrating to the last version") # Reusing the existing engine (initialized by AiiDA) with sa.engine.begin() as connection: alembic_cfg.attributes['connection'] = connection command.upgrade(alembic_cfg, "head") else: print("No migration is performed. Exiting since database is out " "of sync with the code.") sys.exit(1)
[docs]def get_migration_head(config): """ This function returns the head of the migration scripts. :param config: The alembic configuration. :return: The version of the head. """ script = ScriptDirectory.from_config(config) return script.get_current_head()
[docs]def get_db_schema_version(config): """ This function returns the current version of the database. :param config: The alembic configuration. :return: The version of the database. """ if config is None: return None script = ScriptDirectory.from_config(config) def get_db_version(rev, _): if isinstance(rev, tuple) and len(rev) > 0: config.attributes['rev'] = rev[0] else: config.attributes['rev'] = None return [] with EnvironmentContext( config, script, fn=get_db_version ): script.run_env() return config.attributes['rev']
[docs]def get_alembic_conf(): """ This function returns the alembic configuration file contents by doing the necessary updates in the 'script_location' name. :return: The alembic configuration. """ # Constructing the alembic full path & getting the configuration import os dir_path = os.path.dirname(os.path.realpath(__file__)) alembic_fpath = os.path.join(dir_path, ALEMBIC_FILENAME) alembic_cfg = Config(alembic_fpath) # Set the alembic script directory location alembic_dpath = os.path.join(dir_path, ALEMBIC_REL_PATH) alembic_cfg.set_main_option('script_location', alembic_dpath) return alembic_cfg
[docs]def alembic_command(selected_command, *args, **kwargs): """ This function calls the necessary alembic command with the provided arguments. :param selected_command: The command that should be called from the alembic commands. :param args: The arguments. :param kwargs: The keyword arguments. :return: Nothing. """ if selected_command is None: return # Get the requested alembic command from the available commands al_command = getattr(command, selected_command) alembic_cfg = get_alembic_conf() with sa.engine.begin() as connection: alembic_cfg.attributes['connection'] = connection if selected_command in ['current', 'history']: if 'verbose' in args: al_command(alembic_cfg, verbose=True) else: al_command(alembic_cfg, *args, **kwargs) elif selected_command == 'revision': al_command(alembic_cfg, message=args[0][0]) else: al_command(alembic_cfg, *args, **kwargs)
[docs]def delete_nodes_and_connections_sqla(pks_to_delete): """ Delete all nodes corresponding to pks in the input. :param pks_to_delete: A list, tuple or set of pks that should be deleted. """ from aiida.backends import sqlalchemy as sa from aiida.backends.sqlalchemy.models.node import DbNode, DbLink from aiida.backends.sqlalchemy.models.group import table_groups_nodes session = sa.get_scoped_session() try: # I am first making a statement to delete the membership of these nodes to groups. # Since table_groups_nodes is a sqlalchemy.schema.Table, I am using expression language to compile # a stmt to be executed by the session. It works, but it's not nice that two different ways are used! # Can this be changed? stmt = table_groups_nodes.delete().where(table_groups_nodes.c.dbnode_id.in_(list(pks_to_delete))) session.execute(stmt) # First delete links, then the Nodes, since we are not cascading deletions. # Here I delete the links coming out of the nodes marked for deletion. session.query(DbLink).filter(DbLink.input_id.in_(list(pks_to_delete))).delete(synchronize_session='fetch') # Here I delete the links pointing to the nodes marked for deletion. session.query(DbLink).filter(DbLink.output_id.in_(list(pks_to_delete))).delete(synchronize_session='fetch') # Now I am deleting the nodes session.query(DbNode).filter(DbNode.id.in_(list(pks_to_delete))).delete(synchronize_session='fetch') # Here I commit this scoped session! session.commit() except Exception as e: # If there was any exception, I roll back the session. session.rollback() raise e finally: session.close()