SignalWire Python SDK

2.1.1 verified Mon Apr 27 auth: no python

Official Python client library for the SignalWire telecom platform, providing voice, video, messaging, and task router capabilities. Current version 2.1.1 requires Python >=3.6. Released under MIT license.

pip install signalwire

Common errors

error ModuleNotFoundError: No module named 'signalwire.voice' ↓

cause Installed an older version (pre-2.0) that used flat structure.

fix

Upgrade to latest: pip install --upgrade signalwire

error twisted.internet.error.ReactorNotRestartable ↓

cause Calling client.connect() or similar twice in the same process.

fix

Reuse the same client instance across calls, or stop the reactor before restarting.

Warnings

breaking In version 2.0, the package was restructured from flat module to submodules. Old import paths (e.g., from signalwire import Voice) no longer work. ↓

fix Use from signalwire.voice import Voice

gotcha The library requires Twisted as an event loop; it does not work with asyncio out of the box. Running in an asyncio context may block or cause errors. ↓

fix Use Twisted's reactor or run in a separate thread.

deprecated The signalwire.rest submodule for REST API calls is deprecated. Use signalwire.voice or signalwire.messaging methods instead. ↓

fix Use voice.calls.create() or messaging.send() instead of manual REST requests.

Imports

Voice
wrong
```
from signalwire import Voice
```
correct
```
from signalwire.voice import Voice
```
Top-level import fails due to package structure; classes live in submodules.

Messaging

wrong

from signalwire import Messaging

correct

from signalwire.messaging import Messaging

Same issue; must import from submodule.

TaskRouter

wrong

from signalwire import TaskRouter

correct

from signalwire.task_router import TaskRouter

TaskRouter is not exposed at top level.

Quickstart

Initialize a Voice client using environment variables for credentials.

import os
from signalwire.voice import Voice

client = Voice(
    project=os.environ.get('SIGNALWIRE_PROJECT', ''),
    token=os.environ.get('SIGNALWIRE_TOKEN', '')
)
print(client)