asynch

Introduction

asynch is an asyncio ClickHouse Python Driver with native (TCP) interface support, which reuse most of clickhouse-driver and comply with PEP249.

Install

> pip install asynch

or if you want to install clickhouse-cityhash to enable transport compression

> pip install asynch[compression]

Usage

Connect to ClickHouse

from asynch import connect

async def connect_database():
    conn = await connect(
        host = "127.0.0.1",
        port = 9000,
        database = "default",
        user = "default",
        password = "",
    )

Create table by sql

async def create_table():
    async with conn.cursor(cursor=DictCursor) as cursor:
        await cursor.execute('create database if not exists test')
        await cursor.execute("""
        CREATE TABLE if not exists test.asynch
            (
                `id`       Int32,
                `decimal`  Decimal(10, 2),
                `date`     Date,
                `datetime` DateTime,
                `float`    Float32,
                `uuid`     UUID,
                `string`   String,
                `ipv4`     IPv4,
                `ipv6`     IPv6

            )
            ENGINE = MergeTree
                ORDER BY id"""
        )

Use fetchone

async def fetchone():
    async with conn.cursor() as cursor:
        await cursor.execute("SELECT 1")
        ret = await cursor.fetchone()
        assert ret == (1,)

Use fetchmany

async def fetchall():
    async with conn.cursor() as cursor:
        await cursor.execute("SELECT 1")
        ret = await cursor.fetchall()
        assert ret == [(1,)]

Use DictCursor to get result with dict

async def dict_cursor():
    async with conn.cursor(cursor=DictCursor) as cursor:
        await cursor.execute("SELECT 1")
        ret = await cursor.fetchall()
        assert ret == [{"1": 1}]

Insert data with dict

from asynch.cursors import DictCursor

async def insert_dict():
    async with conn.cursor(cursor=DictCursor) as cursor:
        ret = await cursor.execute(
            """INSERT INTO test.asynch(id,decimal,date,datetime,float,uuid,string,ipv4,ipv6) VALUES""",
            [
                {
                    "id": 1,
                    "decimal": 1,
                    "date": "2020-08-08",
                    "datetime": "2020-08-08 00:00:00",
                    "float": 1,
                    "uuid": "59e182c4-545d-4f30-8b32-cefea2d0d5ba",
                    "string": "1",
                    "ipv4": "0.0.0.0",
                    "ipv6": "::",
                }
            ],
        )
        assert ret == 1

Insert data with tuple

async def insert_tuple():
    async with conn.cursor(cursor=DictCursor) as cursor:
        ret = await cursor.execute(
            """INSERT INTO test.asynch(id,decimal,date,datetime,float,uuid,string,ipv4,ipv6) VALUES""",
            [
                (
                    1,
                    1,
                    "2020-08-08",
                    "2020-08-08 00:00:00",
                    1,
                    "59e182c4-545d-4f30-8b32-cefea2d0d5ba",
                    "1",
                    "0.0.0.0",
                    "::",
                )
            ],
        )
        assert ret == 1

Use connection pool

async def use_pool():
    pool = await asynch.create_pool()
    async with pool.acquire() as conn:
        async with conn.cursor() as cursor:
            await cursor.execute("SELECT 1")
            ret = await cursor.fetchone()
            assert ret == (1,)
    pool.close()
    await pool.wait_closed()

ThanksTo

• clickhouse-driver, ClickHouse Python Driver with native interface support.

License

This project is licensed under the Apache-2.0 License.