✨ Support for voxtral realtime stt

[cameledev]

Purpose

Add support for voxtral realtime stt (live transcription).

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[lebaudantoine]

should we make it an env variable?

[lebaudantoine]

we could refactor it to use a factory pattern with a declarative approach based on a decorator.

from typing import Callable, Dict
import os

# Registry of STT provider factories
_STT_PROVIDERS: Dict[str, Callable] = {}


def register_stt_provider(name: str):
    """Decorator to register an STT provider factory."""
    def decorator(func: Callable) -> Callable:
        _STT_PROVIDERS[name] = func
        return func
    return decorator


@register_stt_provider("deepgram")
def _create_deepgram_stt():
    # Note: Not all Deepgram API parameters are supported by the LiveKit plugin.
    # detect_language is NOT supported for real-time streaming.
    # Use language="multi" instead for automatic multilingual support.
    return deepgram.STT(
        model=os.getenv("DEEPGRAM_STT_MODEL", "nova-3"),
        language=os.getenv("DEEPGRAM_STT_LANGUAGE", "multi"),
    )


@register_stt_provider("kyutai")
def _create_kyutai_stt():
    return kyutai.STT(base_url=os.getenv("KYUTAI_STT_BASE_URL"))


@register_stt_provider("voxtral-realtime")
def _create_voxtral_realtime_stt():
    client = Mistral(
        api_key=os.getenv("VOXTRAL_REALTIME_STT_API_KEY"),
        server_url=os.getenv("VOXTRAL_REALTIME_STT_BASE_URL"),
    )
    return mistralai.STT(
        client=client,
        model=os.getenv("VOXTRAL_REALTIME_STT_MODEL", "voxtral-mini-latest"),
    )


def create_stt_provider():
    """Create STT provider based on environment configuration."""
    try:
        factory = _STT_PROVIDERS[STT_PROVIDER]
    except KeyError:
        raise ValueError(
            f"Unknown STT provider: {STT_PROVIDER!r}. "
            f"Available providers: {sorted(_STT_PROVIDERS)}"
        )
    return factory()