Decogres

(python Decorator for PostgresSQL)

Description

This is a small module for maintaining connection pools for an application that connect to a single or connect to multiple databases.

Motivation and Reasoning

Decorators are a crowd favorite for hiding silly things like global state. The idea is to be able to easily recall a database pool that you have already initialized, and continue to use the same pool as your code chugs along using a simple interface. The decorator makes it easy to see that a function touches a database and also implies a larger scope.

Use Cases

Simple stuff like this.

@postgres(**{'name': 'ppp', 'connection_url': "postgresql://postgres:postgres@localhost/"})
def get_42_from_the_database():
    with ppp.cursor() as c:
        c.execute("SELECT 42 AS AMAZING")
    return c.fetchone()['amazing']

@postgres(**{'name': 'black', 'connection_url': "postgresql://postgres:postgres@localhost/black"})
@postgres(**{'name': 'ppp', 'connection_url': "postgresql://postgres:postgres@localhost/"})
def give_me_some_databases():
    return [ppp, black]

"WOW THAT'S AMAZING" You might say. You're not incorrect.

Actual Documentation

the @postgres decorator can take the following keyword arguments

• connection_pool_type: a class of AbstractConnectionPool (defaults to ThreadedConnectionPool)
• connection_url: your postgres url (defaults to "postgresql://postgres:postgres@localhost/")
• name: the name of the connection (defualts to connection_url if not set. please set it)
• mincount: minimum number of connection pool connections (defaults to 2)
• maxcount: maximum number of connection pool connections (defaults to 40)
• cursor_factory: cursor factory to use when creating a cursor with cursor(). (defualts to RealDictCursor)

any other keywords can by found in the actualy psycopg2.pool page.

if I missed anything make a Pull request or something.