asynctnt 0.1.2

A fast Tarantool Database connector for Python/asyncio.

asynctnt is a high-performance Tarantool database connector library for Python/asyncio. It was highly inspired by asyncpg module.

asynctnt requires Python 3.5 or later and is supported for Tarantool versions 1.6+.

Key features

• Support for all of the basic requests that Tarantool supports. This includes: insert, select, update, upsert, eval, call and call16. call16 is an old call method of Tarantool 1.6. call - simplifies return values of Tarantool procedures (please refer to Tarantool documentation for more details).

• Schema fetching on connection establishment, so you can use spaces and indexes names rather than their ids.

• Schema auto refetching. Tarantool has an option to check if “your” schema is up to date, and if not - returns an error. If such an error occurs on any request - new schema is refetched and the initial request is resent.

• Auto reconnect. If connection is lost for some reason - asynctnt will start automatic reconnection procedure (with authorization and schema fetching, of course).

• Ability to use dicts for tuples with field names as keys in DML requests (select, insert, replace, delete, update, upsert). This is possible only if space.format is specified in Tarantool. Field names can also be used in update operations instead of field numbers. Moreover, tuples can be decoded into dicts instead of arrays if tuple_as_dict is True either in Connection or a specific request.

• All requests support specification of timeout value, so if request is executed for too long, asyncio.TimeoutError is raised. It drastically simplifies your code, as you don’t need to use asyncio.wait_for(...) stuff anymore.

Performance

On all of the benchmarks below wal_mode = none

Sequential

RPS on running 40k requests (no uvloop):

Request	aiotarantool	asynctnt
ping	5010.60	9037.07
call	4575.98	9113.32
eval	4096.32	8921.95
select	4063.15	9681.12
insert	4038.04	9332.21
update	3945.12	10532.75

RPS on running 40k requests (with uvloop):

Request	aiotarantool	asynctnt
ping	7204.31	20372.59
call	6723.58	17279.21
eval	7001.27	16642.67
select	7028.03	17730.24
insert	7054.06	17384.26
update	6618.01	15990.12

Parallel coroutines

RPS on running 200k requests in 300 parallel coroutines (no uvloop):

Request	aiotarantool	asynctnt
ping	24961.12	28155.32
call	21748.06	22103.14
eval	20497.69	24417.38
select	19968.26	26151.00
insert	20604.61	22256.69
update	18852.46	23175.80

Let’s enable uvloop. This is where asynctnt shines. RPS on running 200k requests in 300 parallel coroutines (with uvloop):

Request	aiotarantool	asynctnt
ping	30050.55	131317.35
call	27995.62	92207.33
eval	25378.59	80539.26
select	22346.14	88748.47
insert	25811.84	82526.94
update	21914.15	80865.00

Installation

Use pip to install:

$ pip install asynctnt

Basic Usage

Tarantool config:

box.cfg {
    listen = '127.0.0.1:3301'
}

box.once('v1', function()
    box.schema.user.grant('guest', 'read,write,execute', 'universe')

    local s = box.schema.create_space('tester')
    s:create_index('primary')
end)

Python code:

import asyncio
import asynctnt


async def run():
    conn = asynctnt.Connection(host='127.0.0.1', port=3301)
    await conn.connect()

    for i in range(1, 11):
        await conn.insert('tester', [i, 'hello{}'.format(i)])

    values = await conn.select('tester', [])
    print('Code: {}'.format(values.code))
    print('Data: {}'.format(values.body))
    print(values.body2yaml())  # prints as yaml

    await conn.disconnect()

loop = asyncio.get_event_loop()
loop.run_until_complete(run())

License

asynctnt is developed and distributed under the Apache 2.0 license.