mentat.services.sqlstorage module¶

Database storage abstraction layer. The current implementation is based on the awesome SQLAlchemy library accessed by flask_sqlalchemy.

Warning

Current implementation is for optimalization purposes using some advanced schema features provided by the PostgreSQL database and thus no other engines are currently supported.

class mentat.services.sqlstorage.RetryingQuery(entities, session=None)[source]¶

Bases: sqlalchemy.orm.query.Query

An override of SQLAlchemy’s Query class, allowing for recovery from a lost DB connection.

class mentat.services.sqlstorage.StorageService(**enginecfg)[source]¶

Bases: object

Proxy object for working with persistent SQL storages. Maintains and provides access to database engine, session maker and session proxies.

close()[source]¶: Close current database connection.

database_create()[source]¶: Create database SQL schema.

database_drop()[source]¶: Drop database SQL schema.

property session¶

session_close()[source]¶

session_new()[source]¶: Close existing session and create new fresh database session.

class mentat.services.sqlstorage.StorageServiceManager(core_config, updates=None)[source]¶

Bases: object

Class representing a custom _StorageServiceManager_ capable of understanding and parsing Mentat system core configurations and enabling easy access to preconfigured database collections via indirrect handles (identifiers).

close()[source]¶: Close internal storage connection.

service()[source]¶

Return handle to storage connection service according to internal configurations.

Returns: Reference to storage service.
Return type: mentat.services.sqlstorage.StorageService

mentat.services.sqlstorage.close()[source]¶: Close database connection on mentat.services.sqlstorage.StorageService instance from module level manager.

mentat.services.sqlstorage.init(core_config, updates=None)[source]¶

(Re-)Initialize mentat.services.sqlstorage.StorageServiceManager instance at module level and store the refence within module.

Parameters

core_config (dict) – Mentat core configuration structure.
updates (dict) – Optional configuration updates (same structure as core_config).

mentat.services.sqlstorage.manager()[source]¶

Obtain reference to mentat.services.sqlstorage.StorageServiceManager instance stored at module level.

Returns: Storage service manager reference.
Return type: mentat.services.sqlstorage.StorageServiceManager

mentat.services.sqlstorage.service()[source]¶

Obtain reference to mentat.services.sqlstorage.StorageService instance from module level manager.

Returns: Storage service reference.
Return type: mentat.services.sqlstorage.StorageServiceManager

mentat.services.sqlstorage.set_manager(manager)[source]¶: Set manager from outside of the module. This should be used only when you know exactly what you are doing.