alt-python-pynosqlc-redis 1.0.0

Redis driver for pynosqlc

pynosqlc-redis

Redis 7 driver for pynosqlc — a JDBC-inspired unified async NoSQL access layer for Python.

Install this driver to connect pynosqlc to a Redis 7 instance using the redis-py async client. All pynosqlc operations — store, get, insert, update, delete, and find — are supported.

Requirements

• Python 3.12+
• Redis 7.0+ instance (local or remote)
• pynosqlc-core and pynosqlc-memory (installed automatically as dependencies)

Installation

pip install alt-python-pynosqlc-redis

Quick Start

import asyncio
from pynosqlc.core import DriverManager, Filter
import pynosqlc.redis  # auto-registers RedisDriver on import

async def main():
    async with await DriverManager.get_client('pynosqlc:redis://localhost:6379') as client:
        col = client.get_collection('orders')

        # Store a document at a known key (upsert semantics)
        await col.store('order-001', {'item': 'widget', 'qty': 5, 'status': 'pending'})

        # Retrieve a document by key
        doc = await col.get('order-001')
        print(doc)  # {'item': 'widget', 'qty': 5, 'status': 'pending'}

        # Insert a document with a driver-assigned key
        key = await col.insert({'item': 'gadget', 'qty': 2, 'status': 'pending'})
        print(key)  # e.g. 'a1b2c3d4-...'

        # Update fields (shallow merge — only listed fields change)
        await col.update('order-001', {'qty': 10, 'status': 'shipped'})

        # Find documents matching a filter
        f = Filter.where('status').eq('pending').build()
        async for doc in await col.find(f):
            print(doc)

        # Delete a document
        await col.delete('order-001')

asyncio.run(main())

URL Scheme

pynosqlc:redis://<host>:<port>

The pynosqlc: prefix is stripped before the URL is passed to redis-py, so redis:// becomes the effective scheme. Any format accepted by redis.asyncio.from_url can be used, including rediss:// for TLS:

URL	Description
pynosqlc:redis://localhost:6379	Local Redis on the default port
pynosqlc:redis://redis.example.com:6379	Remote Redis instance
pynosqlc:rediss://redis.example.com:6380	Remote Redis with TLS (rediss://)

Storage Layout

Each document and collection index is stored as a separate Redis key:

Redis key	Type	Contents
pynosqlc:<collection>:<doc_key>	String	JSON-serialised document
pynosqlc:<collection>:_keys	Set	All doc keys in the collection

For example, storing a document in the orders collection under key order-001 creates:

• pynosqlc:orders:order-001 → {"item": "widget", "qty": 5}
• pynosqlc:orders:_keys → {"order-001"}

Filtering

Filters are evaluated in-process after fetching all documents from Redis. find() retrieves the entire collection in a single pipeline batch GET, then applies the pynosqlc filter AST in memory using MemoryFilterEvaluator.

There is no server-side query translation. For collections expected to hold large numbers of documents, consider partitioning data into smaller collections or evaluating Redis Search as a complementary tool.

All filter operators are supported: eq, ne, gt, gte, lt, lte, contains, in_, nin, exists, and their and_ / or_ / not_ combinators.

Connection Notes

• All connections use decode_responses=True — values are returned as str, so there is no byte-decoding step before json.loads.
• redis-py's default connection pool is used; pool size is not currently configurable through pynosqlc's properties argument.
• find() uses a Redis pipeline with transaction=False to batch-GET all documents in a single round trip without acquiring a MULTI/EXEC lock.

Troubleshooting

ConnectionError: Error 111 connecting to localhost:6379 Redis is not running or is not reachable on the configured host and port. Verify with redis-cli -h <host> -p <port> ping — you should receive PONG.

ImportError: No module named 'pynosqlc.redis' The package is not installed. Run pip install alt-python-pynosqlc-redis.

ValueError: No driver found for URL ... The import import pynosqlc.redis was not executed before calling DriverManager.get_client(...). The import is what triggers driver registration — it must come before any get_client call.

Filter returns no results despite documents being present Confirm you called .build() at the end of your filter chain: Filter.where('field').eq('value').build(). Passing an unbuilt FieldCondition object instead of the built dict will match nothing.

Further Reading

• pynosqlc API reference — complete method signatures
• Driver implementation guide — how pynosqlc drivers work
• Getting started tutorial — step-by-step introduction