cassandra-asyncio-driver 0.1.4

Wrapper for cassandra-driver that makes queries awaitable using asyncio

Cassandra AsyncIO Driver

Wrapper for cassandra-driver that makes blocking calls awaitable using asyncio

Installation

$ pip install cassandra-asyncio-driver

Usage

To adapt existing code to use the asyncio driver, replace:

from cassandra.cluster import Cluster

with:

from cassandra_asyncio.cluster import Cluster

Queries can be executed asynchronously using await session.aexecute().

For synchronous queries, session.execute() can still be used as normal.

All other Cassandra classes should continue to be imported from the usual paths.

For example:

import csv
import asyncio
from cassandra_asyncio.cluster import Cluster
from cassandra.auth import PlainTextAuthProvider
from cassandra.query import dict_factory

async def main():
    with open('movies.csv', 'w', newline='') as output_file:
        # Prepare CSV writer
        fieldnames = ['genre', 'name', 'rating', 'seen']
        writer = csv.DictWriter(output_file, fieldnames=fieldnames, dialect='excel')
        writer.writeheader()

        # Connect to Cassandra using `cassandra_asyncio.cluster.Cluster`
        auth_provider = PlainTextAuthProvider(username='cassandra', password='cassandra')
        cluster = Cluster(auth_provider=auth_provider)
        session = cluster.connect('lists')
        session.row_factory = dict_factory

        # Execute query asynchronously using `session.aexecute()`
        rows = await session.aexecute('SELECT genre, name, rating, seen FROM movies_to_watch')

        # Write rows to output file
        for row in rows:
            writer.writerow(row)

if __name__ == '__main__':
    asyncio.run(main())