pyApp - SQLAlchemy
Let us handle the boring stuff!
This extension provides a Connection and Session factory for SQLAlchemy to allow database connections to be configured via pyApp settings.
Engine instances are created from a singleton factory to ensure that connection pooling is utilised.
The extension also provides checks to confirm the settings are correct and that the application is able to connect to the database host.
Installation
Install using pip:
pip install pyapp-sqlalchemy
Install using pipenv:
pipenv install pyapp-sqlalchemy
Add pyapp_ext.sqlalchemy into the EXT list in your applications default_settings.py.
Add the DATABASE_ENGINES block into your runtime settings file:
DATABASE_ENGINES = {
"default": {
"url": "postgres://user:pass@host:port/database",
},
}
Note
The URI is a defined by SQLAlchemy see the documentation. In addition to the url any argument that can be provided to sqlalchemy.engines.create_engine can be provided.
Usage
The following example creates both Connection and Session instances:
from pyapp_ext.sqlalchemy import get_connection, get_session
# Get connection from default connection pool
cnn = get_connection()
# Get connection from an alternate pool
session = get_session("Alternate")
API
pyapp_ext.sqlalchemy.get_engine(default: str = None) -> Engine
Get named Engine instance (singleton)
pyapp_ext.sqlalchemy.get_connection(default: str = None) -> Connection
Get named Connection instance.
pyapp_ext.sqlalchemy.get_raw_connection(default: str = None)
Get named raw connection, this is the underlying Python DBAPI object.
pyapp_ext.sqlalchemy.get_session(default: str = None) -> Session
Get named Session instance.
