Replit River

0.17.19 verified Mon Apr 27 auth: no python

Replit River is a Python toolkit for building reliable, bidirectional communication channels (RPC, streaming, etc.) between services, primarily used in the Replit environment. Current version 0.17.19 requires Python 3.12+ and is under active development with frequent releases.

pip install replit-river

Common errors

error ModuleNotFoundError: No module named 'replit_river' ↓

cause Package not installed or misspelled (e.g., 'replit-river' vs 'replit_river').

fix

Run pip install replit-river and use import replit_river (with underscore).

error ImportError: cannot import name 'RiverClient' from 'replit_river' ↓

cause RiverClient is not exported from top-level package; must import from submodule.

fix

Use from replit_river.client import RiverClient.

error TypeError: __init__() got an unexpected keyword argument 'scheme' ↓

cause API changed: `scheme` renamed to `transport` in version 0.17.0.

fix

Replace scheme='ws' with transport='ws'.

Warnings

breaking Python 3.12 minimum: river requires Python >=3.12 (as of 0.17.x). Install may fail on older versions. ↓

fix Upgrade Python to 3.12 or higher.

gotcha RiverClient and RiverServer are not top-level exports: importing from `replit_river` directly does not expose them. Must import from the respective submodules. ↓

fix Use `from replit_river.client import RiverClient` and `from replit_river.server import RiverServer`.

breaking Transport parameter change: in early 0.16.x versions, the transport was specified via `scheme` argument. As of 0.17.x, it's `transport` with values 'ws' or 'http'. ↓

fix Use `transport='ws'` instead of `scheme='ws'`.

Imports

RiverClient

wrong

from river.client import RiverClient

correct

from replit_river.client import RiverClient

Package name is replit_river, not river

RiverServer
wrong
```
from replit_river import RiverServer
```
correct
```
from replit_river.server import RiverServer
```
RiverServer is not in __init__; must import from server submodule

Quickstart

Minimal client example: create RiverClient with WebSocket transport, call a remote procedure.

import asyncio
from replit_river.client import RiverClient

async def main():
    client = RiverClient(url='https://your-service.com', transport='ws')
    # Example: call a remote method
    result = await client.call('greet', {'name': 'World'})
    print(result)

asyncio.run(main())