psycopg2.pool – Connections pooling

Creating new PostgreSQL connections can be an expensive operation. This module offers a few pure Python classes implementing simple connection pooling directly in the client application.

class psycopg2.pool.AbstractConnectionPool(minconn, maxconn, *args, **kwargs)

Base class implementing generic key-based pooling code.

New minconn connections are created automatically. The pool will support a maximum of about maxconn connections. *args and **kwargs are passed to the connect() function.

The following methods are expected to be implemented by subclasses:

getconn(key=None)

Get a free connection and assign it to key if not None.

putconn(conn, key=None, close=False)

Put away a connection.

If close is True, discard the connection from the pool.

closeall()

Close all the connections handled by the pool.

Note that all the connections are closed, including ones eventually in use by the application.

The following classes are AbstractConnectionPool subclasses ready to be used.