tts-voice-creator-clone-and.../routes/conversation.py
mARTin-B78 b3a408bfd9 Fix 422 on text-only conversation turns
UploadFile | None = File(None) with from __future__ import annotations
caused FastAPI to still treat audio as required when omitted.
Changed to Optional[UploadFile] = None (no File() wrapper) so the
field is genuinely optional for text-input turns.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-05-29 14:30:06 +02:00

806 lines
32 KiB
Python

"""Conversation playground, LLM refinement, audio effects, export/import, speak, MCP."""
from __future__ import annotations
import asyncio
import base64
import io
import json
import time
import uuid
import wave
from pathlib import Path
import requests
from typing import Optional
from fastapi import APIRouter, Form, HTTPException, Request, UploadFile
from fastapi.responses import Response, StreamingResponse
from core.config import _load_settings, _save_settings, _clean_preview_backend
from core.constants import _VOICES_DIR_DEFAULT, _MAX_UPLOAD_BYTES
from core.registry import _registry_get, TEMP_DIR
from core.validation import _copy_limited
from core.audio import _to_wav_16k
from core.voice import (
_AUDIO_EXTS, _UPLOAD_EXTS, _PICTURE_EXTS,
_find_voice_audio, _load_meta, _active_voices_dir,
_voice_audio_files, _is_internal_voice_file,
)
from core.tts_helpers import _preview_request_audio
from routes.stt import _transcribe_audio, _clean_stt_backend
router = APIRouter()
# ── LLM helpers ───────────────────────────────────────────────────────────────
def _rewrite_with_persona_sync(text: str, persona: str, llm_url: str, model: str = "") -> str:
"""Inline synchronous persona rewrite; raises RuntimeError on failure."""
system = (
f"Rephrase the user's text as if spoken by this character: {persona}\n"
"Keep the same meaning but adapt vocabulary, tone, and style to the character. "
"Return ONLY the rephrased text — no quotes, no explanation."
)
payload: dict = {
"messages": [
{"role": "system", "content": system},
{"role": "user", "content": text},
],
"temperature": 0.3,
"max_tokens": 512,
}
if model:
payload["model"] = model
resp = requests.post(
f"{llm_url.rstrip('/')}/chat/completions",
json=payload,
headers={"Authorization": "Bearer no-key"},
timeout=60,
)
resp.raise_for_status()
result = resp.json()["choices"][0]["message"]["content"].strip()
if result.startswith('"') and result.endswith('"'):
result = result[1:-1].strip()
return result
def _resolve_speak_voice(settings: dict, client_id: str, explicit_voice: str) -> str:
if explicit_voice:
return explicit_voice
bindings: dict = settings.get("client_voice_bindings") or {}
if client_id and client_id in bindings:
return bindings[client_id]
return settings.get("captures_default_voice") or ""
# ── Routes ────────────────────────────────────────────────────────────────────
@router.post("/api/refine-text")
async def refine_text(request: Request):
"""Clean up raw STT transcription using a local OpenAI-compatible LLM."""
data = await request.json()
text: str = (data.get("text") or "").strip()
llm_url: str = (data.get("llm_url") or "http://localhost:11434/v1").rstrip("/")
model: str = (data.get("model") or "").strip()
toggles: dict = data.get("toggles") or {}
if not text:
raise HTTPException(400, "No text to refine")
rules = []
if toggles.get("fillers", True):
rules.append("Remove filler words (um, uh, like, you know, basically, literally, I mean, so, right, etc.)")
if toggles.get("repetitions", True):
rules.append("Remove repeated words and false starts (e.g. 'the the dog''the dog', 'I was- I was going''I was going')")
if toggles.get("corrections", True):
rules.append("Remove self-corrections and restarts, keeping only the final intended phrasing")
if toggles.get("punctuation", True):
rules.append("Fix punctuation, capitalisation, and sentence boundaries")
if not rules:
return {"text": text, "original": text}
system = (
"You are a transcription cleanup assistant. "
"Apply ONLY the following rules to the user's text. "
"Return ONLY the cleaned text — no explanations, no quotes, no markdown:\n"
+ "\n".join(f"- {r}" for r in rules)
)
payload: dict = {
"messages": [
{"role": "system", "content": system},
{"role": "user", "content": text},
],
"temperature": 0.1,
"max_tokens": 2048,
}
if model:
payload["model"] = model
try:
resp = requests.post(
f"{llm_url}/chat/completions",
json=payload,
headers={"Authorization": "Bearer no-key"},
timeout=60,
)
resp.raise_for_status()
refined = resp.json()["choices"][0]["message"]["content"].strip()
if refined.startswith('"') and refined.endswith('"'):
refined = refined[1:-1].strip()
return {"text": refined, "original": text}
except Exception as e:
raise HTTPException(502, f"LLM refinement failed: {e}")
@router.post("/api/rewrite-with-persona")
async def rewrite_with_persona(request: Request):
"""Rewrite user text in a voice persona's character using a local LLM."""
data = await request.json()
text: str = (data.get("text") or "").strip()
persona: str = (data.get("persona") or "").strip()
llm_url: str = (data.get("llm_url") or "http://localhost:11434/v1").rstrip("/")
model: str = (data.get("model") or "").strip()
mode: str = (data.get("mode") or "rewrite").strip()
if not persona:
raise HTTPException(400, "No persona defined for this voice")
if not text and mode != "compose":
raise HTTPException(400, "No text provided")
if mode == "compose":
system = (
f"You are a voice assistant with this character: {persona}\n"
"Write a single natural utterance in this character's voice about the topic given. "
"Return ONLY the utterance — no quotes, no explanation."
)
user_msg = text or "Introduce yourself briefly."
temp = 0.9
else:
system = (
f"Rephrase the user's text as if spoken by this character: {persona}\n"
"Keep the same meaning but adapt vocabulary, tone, and style to the character. "
"Return ONLY the rephrased text — no quotes, no explanation."
)
user_msg = text
temp = 0.3
payload: dict = {
"messages": [
{"role": "system", "content": system},
{"role": "user", "content": user_msg},
],
"temperature": temp,
"max_tokens": 512,
}
if model:
payload["model"] = model
try:
resp = requests.post(
f"{llm_url}/chat/completions",
json=payload,
headers={"Authorization": "Bearer no-key"},
timeout=60,
)
resp.raise_for_status()
result = resp.json()["choices"][0]["message"]["content"].strip()
if result.startswith('"') and result.endswith('"'):
result = result[1:-1].strip()
return {"text": result, "original": text, "persona": persona}
except Exception as e:
raise HTTPException(502, f"LLM persona rewrite failed: {e}")
# ── Audio effects ─────────────────────────────────────────────────────────────
def _apply_audio_effects(audio_bytes: bytes, effects: list) -> bytes:
try:
from pedalboard import Pedalboard, Reverb, Chorus, Delay, Compressor, Gain, HighpassFilter, LowpassFilter, PitchShift # type: ignore
import numpy as np # type: ignore
except ImportError:
raise RuntimeError("pedalboard is not installed — run: pip install pedalboard numpy")
with io.BytesIO(audio_bytes) as buf:
with wave.open(buf, "rb") as wf:
n_channels = wf.getnchannels()
sample_rate = wf.getframerate()
n_frames = wf.getnframes()
raw = wf.readframes(n_frames)
sampwidth = wf.getsampwidth()
import numpy as np # noqa: F811
dtype = {1: np.int8, 2: np.int16, 4: np.int32}.get(sampwidth, np.int16)
samples = np.frombuffer(raw, dtype=dtype).astype(np.float32) / float(np.iinfo(dtype).max)
samples = samples.reshape(1, -1) if n_channels == 1 else samples.reshape(-1, n_channels).T
board = []
for fx in effects:
t = fx.get("type", "")
p = fx.get("params", {})
if t == "reverb":
board.append(Reverb(
room_size=float(p.get("room_size", 0.35)),
damping=float(p.get("damping", 0.5)),
wet_level=float(p.get("wet", 0.25)),
dry_level=float(p.get("dry", 0.8)),
))
elif t == "chorus":
board.append(Chorus(
rate_hz=float(p.get("rate_hz", 1.0)),
depth=float(p.get("depth", 0.25)),
mix=float(p.get("mix", 0.5)),
))
elif t == "delay":
board.append(Delay(
delay_seconds=float(p.get("delay_s", 0.25)),
feedback=float(p.get("feedback", 0.3)),
mix=float(p.get("mix", 0.4)),
))
elif t == "compressor":
board.append(Compressor(
threshold_db=float(p.get("threshold_db", -20.0)),
ratio=float(p.get("ratio", 4.0)),
attack_ms=float(p.get("attack_ms", 10.0)),
release_ms=float(p.get("release_ms", 100.0)),
))
elif t == "gain":
board.append(Gain(gain_db=float(p.get("gain_db", 0.0))))
elif t == "highpass":
board.append(HighpassFilter(cutoff_frequency_hz=float(p.get("cutoff_hz", 80.0))))
elif t == "lowpass":
board.append(LowpassFilter(cutoff_frequency_hz=float(p.get("cutoff_hz", 8000.0))))
elif t == "pitch_shift":
board.append(PitchShift(semitones=float(p.get("semitones", 0.0))))
if board:
samples = Pedalboard(board)(samples, sample_rate)
out = np.clip(samples, -1.0, 1.0)
pcm = ((out[0] if out.shape[0] == 1 else out.T.reshape(-1)) * 32767).astype(np.int16).tobytes()
buf_out = io.BytesIO()
with wave.open(buf_out, "wb") as wf:
wf.setnchannels(n_channels)
wf.setsampwidth(2)
wf.setframerate(sample_rate)
wf.writeframes(pcm)
return buf_out.getvalue()
@router.post("/api/audio/effects")
async def audio_effects(request: Request):
"""Apply an effects chain to a WAV file."""
form = await request.form()
audio_file = form.get("audio")
effects_json = str(form.get("effects") or "[]")
if audio_file is None:
raise HTTPException(400, "No audio file provided")
audio_bytes = await audio_file.read()
try:
effects = json.loads(effects_json)
except Exception:
raise HTTPException(400, "Invalid effects JSON")
try:
result = await asyncio.to_thread(_apply_audio_effects, audio_bytes, effects)
return Response(content=result, media_type="audio/wav")
except RuntimeError as e:
raise HTTPException(501, str(e))
except Exception as e:
raise HTTPException(500, f"Effects processing failed: {e}")
# ── Voices export / import ────────────────────────────────────────────────────
_EXPORT_SKIP_KEYS = {"groq_api_key", "whisper_api_key", "tts_api_key", "voice_design_api_key", "elevenlabs_api_key"}
_IMPORT_ALLOWED_SUFFIXES = set(_AUDIO_EXTS + [".reference.txt", ".meta.json", ".jpg", ".jpeg", ".png", ".webp"])
@router.get("/api/voices/export")
async def voices_export():
"""Export all voices + non-sensitive settings as a ZIP archive."""
import zipfile
from datetime import datetime
settings = _load_settings()
scan_dir = Path(settings.get("voices_scan_dir", _VOICES_DIR_DEFAULT))
buf = io.BytesIO()
with zipfile.ZipFile(buf, "w", zipfile.ZIP_DEFLATED) as zf:
safe_settings = {k: v for k, v in settings.items() if k not in _EXPORT_SKIP_KEYS}
zf.writestr("settings.json", json.dumps(safe_settings, indent=2))
if scan_dir.exists():
for f in scan_dir.rglob("*"):
if f.is_file():
try:
zf.write(f, str(f.relative_to(scan_dir.parent)))
except Exception:
pass
buf.seek(0)
ts = datetime.now().strftime("%Y%m%d_%H%M%S")
return Response(
content=buf.read(),
media_type="application/zip",
headers={"Content-Disposition": f'attachment; filename="voices_export_{ts}.zip"'},
)
@router.post("/api/voices/import")
async def voices_import(file: UploadFile = File(...)):
"""Import voices from a ZIP archive (skips settings.json and unsafe paths)."""
import zipfile
settings = _load_settings()
scan_dir = Path(settings.get("voices_scan_dir", _VOICES_DIR_DEFAULT))
scan_dir.mkdir(parents=True, exist_ok=True)
content = await file.read()
if len(content) > _MAX_UPLOAD_BYTES:
raise HTTPException(413, "ZIP file too large")
try:
imported = 0
with zipfile.ZipFile(io.BytesIO(content)) as zf:
for info in zf.infolist():
if info.is_dir():
continue
parts = Path(info.filename).parts
if any(p in ("..", "") for p in parts) or Path(info.filename).name == "settings.json":
continue
if Path(info.filename).suffix.lower() not in _IMPORT_ALLOWED_SUFFIXES:
continue
rel = parts[1:] if len(parts) > 1 else parts
dest = scan_dir / Path(*rel)
dest.parent.mkdir(parents=True, exist_ok=True)
dest.write_bytes(zf.read(info))
imported += 1
except zipfile.BadZipFile:
raise HTTPException(400, "Not a valid ZIP file")
except Exception as e:
raise HTTPException(500, f"Import failed: {e}")
return {"ok": True, "imported": imported}
# ── /speak REST endpoint ──────────────────────────────────────────────────────
@router.post("/speak")
async def speak(request: Request):
data = await request.json()
text: str = str(data.get("text") or "").strip()
if not text:
raise HTTPException(400, "text is required")
explicit_voice: str = str(data.get("voice") or data.get("profile_id") or data.get("profile") or "").strip()
backend: str = _clean_preview_backend(str(data.get("backend") or "voice_clone"))
apply_persona: bool = bool(data.get("apply_persona") or data.get("personality"))
client_id: str = request.headers.get("X-Voice-Creator-Client-Id", "").strip()
settings = _load_settings()
voice = _resolve_speak_voice(settings, client_id, explicit_voice)
if not voice:
raise HTTPException(400, "No voice specified and no default voice configured")
if apply_persona:
scan_dir = Path(settings.get("voices_scan_dir", _VOICES_DIR_DEFAULT))
wav = _find_voice_audio(voice, scan_dir)
if wav:
persona = _load_meta(wav).get("persona", "")
if persona:
llm_url = (settings.get("llm_url") or "http://localhost:11434/v1").rstrip("/")
try:
text = await asyncio.to_thread(_rewrite_with_persona_sync, text, persona, llm_url)
except Exception as e:
raise HTTPException(502, f"Persona rewrite failed: {e}")
instruct = str(data.get("instruct") or "")
try:
audio, media_type = await asyncio.to_thread(
_preview_request_audio, text, voice, settings, instruct, backend
)
except Exception as e:
raise HTTPException(502, f"TTS error: {e}")
return Response(content=audio, media_type=media_type)
@router.get("/speak/bindings")
async def get_speak_bindings():
s = _load_settings()
return {"bindings": s.get("client_voice_bindings") or {}}
@router.put("/speak/bindings/{client_id}")
async def put_speak_binding(client_id: str, request: Request):
data = await request.json()
voice = str(data.get("voice") or "").strip()
if not voice:
raise HTTPException(400, "voice is required")
s = _load_settings()
bindings: dict = dict(s.get("client_voice_bindings") or {})
bindings[client_id] = voice
s["client_voice_bindings"] = bindings
_save_settings(s)
return {"ok": True, "client_id": client_id, "voice": voice}
@router.delete("/speak/bindings/{client_id}")
async def delete_speak_binding(client_id: str):
s = _load_settings()
bindings: dict = dict(s.get("client_voice_bindings") or {})
if client_id not in bindings:
raise HTTPException(404, f"No binding for client '{client_id}'")
del bindings[client_id]
s["client_voice_bindings"] = bindings
_save_settings(s)
return {"ok": True, "client_id": client_id}
# ── MCP JSON-RPC 2.0 server ───────────────────────────────────────────────────
_MCP_SERVER_INFO = {"name": "tts-voice-creator", "version": "1.0.0"}
_MCP_TOOLS = [
{
"name": "speak",
"description": "Generate speech audio from text using a cloned voice. Returns a data URI with the WAV audio.",
"inputSchema": {
"type": "object",
"properties": {
"text": {"type": "string", "description": "Text to synthesize"},
"voice": {"type": "string", "description": "Voice ID (optional — uses per-client binding or default if omitted)"},
"apply_persona": {"type": "boolean", "description": "Rewrite text through the voice's persona before synthesis"},
},
"required": ["text"],
},
},
{
"name": "transcribe",
"description": "Transcribe base64-encoded WAV audio to text.",
"inputSchema": {
"type": "object",
"properties": {
"audio_base64": {"type": "string", "description": "Base64-encoded audio bytes (WAV preferred)"},
},
"required": ["audio_base64"],
},
},
{
"name": "list_captures",
"description": "List the 20 most recently generated audio files.",
"inputSchema": {"type": "object", "properties": {}},
},
{
"name": "list_profiles",
"description": "List all available voice profiles with their language, persona, and enabled state.",
"inputSchema": {"type": "object", "properties": {}},
},
]
async def _mcp_tool_speak(args: dict, client_id: str) -> dict:
text = str(args.get("text") or "").strip()
if not text:
raise ValueError("text is required")
explicit_voice = str(args.get("voice") or "").strip()
apply_persona = bool(args.get("apply_persona", False))
settings = _load_settings()
voice = _resolve_speak_voice(settings, client_id, explicit_voice)
if not voice:
raise ValueError("No voice specified and no default voice configured")
if apply_persona:
scan_dir = Path(settings.get("voices_scan_dir", _VOICES_DIR_DEFAULT))
wav = _find_voice_audio(voice, scan_dir)
if wav:
persona = _load_meta(wav).get("persona", "")
if persona:
llm_url = (settings.get("llm_url") or "http://localhost:11434/v1").rstrip("/")
text = await asyncio.to_thread(_rewrite_with_persona_sync, text, persona, llm_url)
audio, _media_type = await asyncio.to_thread(
_preview_request_audio, text, voice, settings, "", "voice_clone"
)
audio_b64 = base64.b64encode(audio).decode()
return {
"content": [
{"type": "text", "text": f"Generated {len(audio)} bytes of speech audio for voice '{voice}'."},
{"type": "resource", "resource": {"uri": f"data:audio/wav;base64,{audio_b64}", "mimeType": "audio/wav"}},
]
}
async def _mcp_tool_transcribe(args: dict) -> dict:
raw = args.get("audio_base64") or ""
try:
audio_bytes = base64.b64decode(raw)
except Exception:
raise ValueError("audio_base64 is not valid base64")
tmp = TEMP_DIR / f"{uuid.uuid4().hex}_mcp_transcribe.wav"
tmp.write_bytes(audio_bytes)
settings = _load_settings()
try:
text, used_backend = await asyncio.to_thread(_transcribe_audio, tmp, settings, "configured")
finally:
try:
tmp.unlink(missing_ok=True)
except Exception:
pass
return {"content": [{"type": "text", "text": text}], "backend": used_backend}
async def _mcp_tool_list_captures() -> dict:
settings = _load_settings()
out_dir = _active_voices_dir(settings)
if not out_dir.exists():
return {"content": [{"type": "text", "text": "[]"}]}
files = sorted(
(p for p in out_dir.rglob("*.wav") if not _is_internal_voice_file(p)),
key=lambda p: p.stat().st_mtime,
reverse=True,
)[:20]
result = [{"name": p.stem, "path": str(p), "mtime": p.stat().st_mtime} for p in files]
return {"content": [{"type": "text", "text": json.dumps(result)}]}
async def _mcp_tool_list_profiles() -> dict:
settings = _load_settings()
scan_dir = Path(settings.get("voices_scan_dir", _VOICES_DIR_DEFAULT))
profiles = []
seen: set[str] = set()
for audio in sorted(_voice_audio_files(scan_dir), key=lambda p: p.stem.lower()):
if audio.stem in seen:
continue
seen.add(audio.stem)
meta = _load_meta(audio)
parts = audio.stem.split("_", 2)
lang = parts[0].upper() if parts else ""
profiles.append({
"id": audio.stem,
"name": audio.stem,
"lang": lang,
"persona": meta.get("persona", ""),
"enabled": meta.get("enabled", True),
})
return {"content": [{"type": "text", "text": json.dumps(profiles)}]}
def _mcp_error_response(code: int, message: str, rpc_id) -> Response:
import logging
body = {"jsonrpc": "2.0", "error": {"code": code, "message": message}, "id": rpc_id}
return Response(content=json.dumps(body), media_type="application/json")
@router.post("/mcp")
async def mcp_jsonrpc(request: Request):
import logging
logger = logging.getLogger("uvicorn.error")
try:
body = await request.json()
except Exception:
return _mcp_error_response(-32700, "Parse error", None)
rpc_id = body.get("id")
method = body.get("method", "")
params = body.get("params") or {}
client_id = request.headers.get("X-Voice-Creator-Client-Id", "").strip()
try:
if method == "initialize":
result = {
"protocolVersion": "2024-11-05",
"serverInfo": _MCP_SERVER_INFO,
"capabilities": {"tools": {}},
}
elif method == "notifications/initialized":
return Response(status_code=204)
elif method == "tools/list":
result = {"tools": _MCP_TOOLS}
elif method == "tools/call":
tool_name = str(params.get("name") or "")
tool_args = params.get("arguments") or {}
if tool_name == "speak":
result = await _mcp_tool_speak(tool_args, client_id)
elif tool_name == "transcribe":
result = await _mcp_tool_transcribe(tool_args)
elif tool_name == "list_captures":
result = await _mcp_tool_list_captures()
elif tool_name == "list_profiles":
result = await _mcp_tool_list_profiles()
else:
return _mcp_error_response(-32601, f"Unknown tool: {tool_name}", rpc_id)
else:
return _mcp_error_response(-32601, f"Method not found: {method}", rpc_id)
except ValueError as e:
return _mcp_error_response(-32602, str(e), rpc_id)
except Exception as e:
logger.exception("MCP tool error in method %s", method)
return _mcp_error_response(-32000, f"Server error: {e}", rpc_id)
return Response(
content=json.dumps({"jsonrpc": "2.0", "result": result, "id": rpc_id}),
media_type="application/json",
)
@router.get("/mcp")
async def mcp_sse(request: Request):
"""SSE keep-alive stream (satisfies MCP spec GET /mcp requirement)."""
from typing import AsyncGenerator
async def _keepalive() -> AsyncGenerator[str, None]:
yield ": mcp-sse-ready\n\n"
while True:
await asyncio.sleep(15)
yield ": ping\n\n"
return StreamingResponse(
_keepalive(),
media_type="text/event-stream",
headers={"Cache-Control": "no-cache", "X-Accel-Buffering": "no"},
)
# ── Conversation playground ───────────────────────────────────────────────────
@router.get("/api/conversation/llm-models")
async def conversation_llm_models(url: str = ""):
"""List models from a local LLM endpoint (Ollama / vLLM / LM Studio)."""
from core.validation import _validate_http_url
settings = _load_settings()
base = (url or settings.get("llm_url") or "http://localhost:11434/v1").rstrip("/")
try:
base = _validate_http_url(base, allow_private=True)
r = requests.get(f"{base}/models", timeout=5, headers={"Authorization": "Bearer no-key"})
if r.status_code == 200:
payload = r.json()
data = payload.get("data", []) if isinstance(payload, dict) else []
models = [
str(item["id"]) if isinstance(item, dict) and item.get("id") else str(item)
for item in data if item
]
return {"models": models, "url": base}
except Exception:
pass
return {"models": [], "url": base}
@router.post("/api/conversation/turn")
async def conversation_turn(
audio: Optional[UploadFile] = None,
text: str = Form(""),
stt_backend: str = Form("configured"),
llm_url: str = Form(""),
llm_model: str = Form(""),
tts_backend: str = Form("voice_clone"),
tts_voice: str = Form(""),
system_prompt: str = Form("You are a helpful voice assistant. Keep replies short and conversational."),
history: str = Form("[]"),
):
"""Stream a full conversation turn (STT → LLM → TTS) as Server-Sent Events.
Pass either an audio file (runs STT first) or a plain text string (skips STT).
"""
direct_text = text.strip()
if not direct_text and (audio is None or not getattr(audio, "filename", None)):
raise HTTPException(400, "Provide either an audio file or a text field")
settings = _load_settings()
eff_llm_url = (llm_url or settings.get("llm_url") or "http://localhost:11434/v1").rstrip("/")
# Prepare audio temp files only when an audio upload was provided
_tmp: Path | None = None
_wav: Path | None = None
if not direct_text and audio is not None:
suffix = Path(audio.filename or "audio.webm").suffix.lower() or ".webm"
if suffix not in _UPLOAD_EXTS:
suffix = ".webm"
_tmp = TEMP_DIR / f"{uuid.uuid4().hex}_conv{suffix}"
try:
with _tmp.open("wb") as f:
_copy_limited(audio.file, f, _MAX_UPLOAD_BYTES)
_wav = _to_wav_16k(_tmp)
except Exception as e:
_tmp.unlink(missing_ok=True)
raise HTTPException(400, f"Audio upload failed: {e}")
try:
hist = json.loads(history) if history else []
if not isinstance(hist, list):
hist = []
except Exception:
hist = []
stt_be = _clean_stt_backend(stt_backend)
tts_be = _clean_preview_backend(tts_backend)
async def generate():
t0 = time.monotonic()
stt_ms = llm_ttft_ms = llm_total_ms = tts_ms = None
transcript = llm_text = ""
def sse(obj: dict) -> str:
return f"data: {json.dumps(obj)}\n\n"
# 1. STT — skipped when caller sends direct text
if direct_text:
transcript = direct_text
yield sse({"type": "transcript", "text": transcript, "stt_ms": None})
else:
try:
t_stt = time.monotonic()
transcript, _ = await asyncio.to_thread(_transcribe_audio, _wav, settings, stt_be)
stt_ms = int((time.monotonic() - t_stt) * 1000)
yield sse({"type": "transcript", "text": transcript, "stt_ms": stt_ms})
except Exception as e:
yield sse({"type": "error", "stage": "stt", "message": str(e)})
return
finally:
for p in filter(None, {_tmp, _wav}):
with contextlib.suppress(Exception):
p.unlink(missing_ok=True)
if not transcript.strip():
yield sse({"type": "error", "stage": "stt", "message": "No speech detected."})
return
# 2. LLM stream
messages = [{"role": "system", "content": system_prompt}]
messages.extend(hist[-20:])
messages.append({"role": "user", "content": transcript})
llm_payload: dict = {"messages": messages, "stream": True, "temperature": 0.7, "max_tokens": 512}
if llm_model:
llm_payload["model"] = llm_model
try:
t_llm = time.monotonic()
llm_resp = await asyncio.to_thread(lambda: requests.post(
f"{eff_llm_url}/chat/completions", json=llm_payload,
headers={"Authorization": "Bearer no-key"}, stream=True, timeout=120,
))
llm_resp.raise_for_status()
ttft_done = False
for raw_line in llm_resp.iter_lines():
if not raw_line:
continue
line = raw_line.decode("utf-8") if isinstance(raw_line, bytes) else str(raw_line)
if not line.startswith("data:"):
continue
chunk = line[5:].strip()
if chunk == "[DONE]":
break
try:
obj = json.loads(chunk)
delta = ((obj.get("choices") or [{}])[0].get("delta") or {}).get("content") or ""
if not delta and isinstance(obj.get("message"), dict):
delta = obj["message"].get("content") or ""
if delta:
if not ttft_done:
llm_ttft_ms = int((time.monotonic() - t_llm) * 1000)
ttft_done = True
llm_text += delta
yield sse({"type": "token", "delta": delta})
except Exception:
continue
llm_total_ms = int((time.monotonic() - t_llm) * 1000)
yield sse({"type": "llm_done", "text": llm_text,
"llm_ttft_ms": llm_ttft_ms, "llm_total_ms": llm_total_ms})
except Exception as e:
yield sse({"type": "error", "stage": "llm", "message": str(e)})
return
if not llm_text.strip():
yield sse({"type": "error", "stage": "llm", "message": "LLM returned empty response."})
return
# 3. TTS
try:
t_tts = time.monotonic()
audio_bytes, mime = await asyncio.to_thread(
_preview_request_audio, llm_text, tts_voice, settings, "", tts_be
)
tts_ms = int((time.monotonic() - t_tts) * 1000)
total_ms = int((time.monotonic() - t0) * 1000)
yield sse({"type": "audio", "b64": base64.b64encode(audio_bytes).decode(), "mime": mime})
yield sse({"type": "stats", "stt_ms": stt_ms, "llm_ttft_ms": llm_ttft_ms,
"llm_total_ms": llm_total_ms, "tts_ms": tts_ms, "total_ms": total_ms})
except Exception as e:
yield sse({"type": "error", "stage": "tts", "message": str(e)})
return
yield sse({"type": "done"})
return StreamingResponse(generate(), media_type="text/event-stream",
headers={"Cache-Control": "no-cache", "X-Accel-Buffering": "no"})