Constants and Enums
- class falcon_sqla.constants.EngineRole(value)
Engine role in
Manager
.- READ = 'r'
This engine is only suitable for reading (e.g., a read replica).
- READ_WRITE = 'rw'
This engine is suitable for all types of queries.
When
choosing
, this engine will participate in balancing load in bothREAD
andWRITE
contexts (unlessread_from_rw_engines
is set toTrue
).
- WRITE = 'w'
This engine is only preferred for writing.
- class falcon_sqla.constants.SessionCleanup(value)
Session cleanup behavior.
Sessions are automatically cleaned up and returned to the pool when using
Manager
'ssession_scope()
ormiddleware
. In addition to closing the session, to the mode-specific behavior is governed by the below constants.Unless configured otherwise, the default behavior throughout this add-on is
COMMIT_ON_SUCCESS
.Note
Customizable session cleanup complements SQLAlchemy’s “reset on return” behaviour, see also: https://docs.sqlalchemy.org/en/20/core/pooling.html#pool-reset-on-return.
- CLOSE_ONLY = 'close'
Close only.
This mode only closes the session. Any commit or rollback should be performed explicitly in the code.
- COMMIT = 'commit'
Always commit.
This mode always attempts to commit regardless of any exceptions raised.
Even if the commit attempt raises an exception, no rollback is performed.
- COMMIT_ON_SUCCESS = 'default'
Commit on success (the default behavior).
This mode attempts to commit in the case there was no exception raised in the block in question (or in the case of middleware, request-response cycle), otherwise rollback.
In this mode, in the case the attempt to commit results in an exception itself, it is also followed up with a rollback.
- ROLLBACK = 'rollback'
Rollback.
This mode always attempts to roll back regardless of any exceptions raised.