EvidentSource Client for Python

Python client for the EvidentSource event sourcing database.

Installation

pip install evidentsource-client

Usage

import asyncio
from evidentsource_client import EvidentSource
from evidentsource_core import DatabaseName, Selector, ProspectiveEvent, StringEventData

async def main():
    # Connect to the server
    async with await EvidentSource.connect("localhost:50051") as es:
        # Create a database
        db_name = DatabaseName("my-app")
        await es.create_database(db_name)

        # Connect to the database
        conn = await es.connect_database(db_name)

        # Transact events
        events = [
            ProspectiveEvent(
                id="evt-1",
                stream="orders",
                event_type="OrderCreated",
                data=StringEventData('{"orderId": "123"}'),
            )
        ]
        db = await conn.transact(events)
        print(f"Committed at revision: {db.revision}")

        # Query events
        db = await conn.latest_database()
        async for event in db.query_events(Selector.stream("orders")):
            print(f"Event: {event.id} - {event.event_type}")

asyncio.run(main())

API

EvidentSource

The main entry point for connecting to an EvidentSource server.

• EvidentSource.connect(address) - Connect to a server
• create_database(name) - Create a new database
• connect_database(name) - Connect to an existing database

Connection

Represents a connection to a specific database.

• transact(events, constraints?) - Commit events atomically
• latest_database() - Get the latest database state

DatabaseAtRevision

A point-in-time view of the database.

• query_events(selector) - Query events matching a selector
• view_state(name, version, params) - Get a state view

License

MIT OR Apache-2.0