| commit | author | age | ||
| 4b23c9 | 1 | from sqlalchemy import engine_from_config |
| MM | 2 | from sqlalchemy.orm import sessionmaker |
| 73c256 | 3 | from sqlalchemy.orm import configure_mappers |
| 4b23c9 | 4 | import zope.sqlalchemy |
| MM | 5 | |
| 6 | # import or define all models here to ensure they are attached to the | |
| 7 | # Base.metadata prior to any initialization routines | |
| ba7ab2 | 8 | from .page import Page # noqa |
| JB | 9 | from .user import User # noqa |
| 73c256 | 10 | |
| 4b23c9 | 11 | # run configure_mappers after defining all of the models to ensure |
| MM | 12 | # all relationships can be setup |
| 73c256 | 13 | configure_mappers() |
| 4b23c9 | 14 | |
| MM | 15 | |
| 16 | def get_engine(settings, prefix='sqlalchemy.'): | |
| 17 | return engine_from_config(settings, prefix) | |
| 18 | ||
| 19 | ||
| 20 | def get_session_factory(engine): | |
| 21 | factory = sessionmaker() | |
| 22 | factory.configure(bind=engine) | |
| 23 | return factory | |
| 24 | ||
| 25 | ||
| 26 | def get_tm_session(session_factory, transaction_manager): | |
| 27 | """ | |
| 28 | Get a ``sqlalchemy.orm.Session`` instance backed by a transaction. | |
| 29 | ||
| 30 | This function will hook the session to the transaction manager which | |
| 31 | will take care of committing any changes. | |
| 32 | ||
| 33 | - When using pyramid_tm it will automatically be committed or aborted | |
| 34 | depending on whether an exception is raised. | |
| 35 | ||
| 36 | - When using scripts you should wrap the session in a manager yourself. | |
| 37 | For example:: | |
| 38 | ||
| 39 | import transaction | |
| 40 | ||
| 41 | engine = get_engine(settings) | |
| 42 | session_factory = get_session_factory(engine) | |
| 43 | with transaction.manager: | |
| 44 | dbsession = get_tm_session(session_factory, transaction.manager) | |
| 45 | ||
| 46 | """ | |
| 47 | dbsession = session_factory() | |
| 48 | zope.sqlalchemy.register( | |
| 49 | dbsession, transaction_manager=transaction_manager) | |
| 50 | return dbsession | |
| 51 | ||
| 52 | ||
| 53 | def includeme(config): | |
| 54 | """ | |
| 55 | Initialize the model for a Pyramid app. | |
| 56 | ||
| 57 | Activate this setup using ``config.include('tutorial.models')``. | |
| 58 | ||
| 59 | """ | |
| 60 | settings = config.get_settings() | |
| d83888 | 61 | settings['tm.manager_hook'] = 'pyramid_tm.explicit_manager' |
| 4b23c9 | 62 | |
| MM | 63 | # use pyramid_tm to hook the transaction lifecycle to the request |
| 64 | config.include('pyramid_tm') | |
| 65 | ||
| 2c0e3e | 66 | # use pyramid_retry to retry a request when transient exceptions occur |
| SP | 67 | config.include('pyramid_retry') |
| 68 | ||
| 4b23c9 | 69 | session_factory = get_session_factory(get_engine(settings)) |
| 1c1080 | 70 | config.registry['dbsession_factory'] = session_factory |
| 4b23c9 | 71 | |
| MM | 72 | # make request.dbsession available for use in Pyramid |
| 73 | config.add_request_method( | |
| 74 | # r.tm is the transaction manager used by pyramid_tm | |
| 75 | lambda r: get_tm_session(session_factory, r.tm), | |
| 76 | 'dbsession', | |
| 77 | reify=True | |
| 78 | ) | |
