PostgreSQL

Supported drivers:

dbapi	default	driver	connection class
psycopg2		postgresql+psycopg2	psycopg2.extensions.connection
psycopg3		postgresql+psycopg	psycopg.Connection
aiopg		postgresql+aiopg	aiopg.connection.Connection

psycopg2

psycopg2 is the default dbapi driver for PostgreSQL in pydapper.

Installation

pippoetry

pip install pydapper[psycopg2]

poetry add pydapper -E psycopg2

DSN format

TemplateExampleExample (Default Driver)

dsn = f"postgresql+psycopg2://{user}:{password}@{host}:{port}/{dbname}"

dsn = "postgresql+psycopg2://myuser:mypassword:1521@localhost/mydb"

dsn = "postgresql://myuser:mypassword:1521@localhost/mydb"

Example - connect

Please see the psycopg2 docs for a full description of the context manager behavior.

import pydapper

with pydapper.connect("postgresql://pydapper:pydapper@localhost/pydapper") as commands:
    print(type(commands))
    # <class 'pydapper.postgresql.psycopg2.Psycopg2Commands'>

    print(type(commands.connection))
    # <class 'psycopg2.extensions.connection'>

    with commands.cursor() as raw_cursor:
        print(type(raw_cursor))
        # <class 'psycopg2.extensions.cursor'>

The `psycopg2` context manager does not close your connection...

You must close it explicitly after exiting the context block:

with connect("postgresql://pydapper:pydapper@localhost/pydapper") as commands:
    # do stuff

# connection is still open, lets close it
commands.connection.close()

Example - using

Use pydapper with a psycopg2 connection pool.

from psycopg2.pool import SimpleConnectionPool

import pydapper

my_pool = SimpleConnectionPool(1, 10, "postgresql://pydapper:pydapper@localhost/pydapper")


commands = pydapper.using(my_pool.getconn())
print(type(commands))
# <class 'pydapper.postgresql.psycopg2.Psycopg2Commands'>

print(type(commands.connection))
# <class 'psycopg2.extensions.connection'>

my_pool.putconn(commands.connection)

psycopg3

Installation

pippoetry

pip install pydapper[psycopg]

poetry add pydapper -E psycopg

DSN format

TemplateExample

dsn = f"postgresql+psycopg://{user}:{password}@{host}:{port}/{dbname}"

dsn = "postgresql+psycopg://myuser:mypassword:1521@localhost/mydb"

Example - connect

Please see the psycopg docs for a full description of the context manager behavior.

import pydapper

with pydapper.connect("postgresql+psycopg://pydapper:pydapper@localhost/pydapper") as commands:
    print(type(commands))
    # <class 'pydapper.postgresql.psycopg3.Psycopg3Commands'>

    print(type(commands.connection))
    # <class 'psycopg.Connection'>

    with commands.cursor() as raw_cursor:
        print(type(raw_cursor))
        # <class 'psycopg.Cursor'>

Example - using

Use pydapper with a psycopg connection pool. Package that handles connection pools is distributed separately from the main package.

pippoetry

pip install psycopg_pool

poetry add psycopg_pool

from psycopg_pool import ConnectionPool

import pydapper

my_pool = ConnectionPool("postgresql://pydapper:pydapper@localhost/pydapper", min_size=1, max_size=10)

commands = pydapper.using(my_pool.getconn())
print(type(commands))
# <class 'pydapper.postgresql.psycopg3.Psycopg3Commands'>

print(type(commands.connection))
# <class 'psycopg.Connection'>

my_pool.putconn(commands.connection)

aiopg

Installation

pippoetry

pip install pydapper[aiopg]

poetry add pydapper -E aiopg

DSN format

TemplateExample

dsn = f"postgresql+aiopg://{user}:{password}@{host}:{port}/{dbname}"

dsn = "postgresql+aiopg://myuser:mypassword:1521@localhost/mydb"

Example - connect_async

Please see the aiopg docs for a full description of the context manager behavior.

import asyncio

import pydapper


async def main():
    async with pydapper.connect_async("postgresql+aiopg://pydapper:pydapper@localhost/pydapper") as commands:
        print(type(commands))
        # <class 'pydapper.postgresql.aiopg.AiopgCommands'>

        print(type(commands.connection))
        # <class 'aiopg.connection.Connection'>

        async with commands.cursor() as raw_cursor:
            print(type(raw_cursor))
            # <class 'aiopg.connection.Cursor'>


asyncio.run(main())

Note

aiopg always runs in autocommit mode.

Example - using_async

Use pydapper with a aiopg connection pool.

import asyncio

import aiopg

import pydapper


async def main():
    async with aiopg.create_pool("postgresql://pydapper:pydapper@localhost/pydapper") as pool:
        conn = await pool.acquire()
        async with pydapper.using_async(conn) as commands:
            print(type(commands))
            # <class 'pydapper.postgresql.aiopg.AiopgCommands'>

            print(type(commands.connection))
            # <class 'aiopg.connection.Connection'>


asyncio.run(main())