dograh/api/services/pipecat/realtime/ultravox_realtime.py
Abhishek 01acf6ac30
fix: fix speech to speech model transitions (#545)
* fix: fix transition logic for realtime providers

* chore: run formatter

* chore: generate SDK and fix other realtime providers

* fix: fix ultravox node transitions
2026-07-15 18:36:36 +05:30

516 lines
20 KiB
Python

"""Dograh subclass of pipecat's Ultravox realtime LLM service.
Ultravox is audio-native and realtime. Its native call stages allow a client
tool result to atomically change the system prompt and tools while preserving
the call's server-side conversation history. This wrapper adapts that model to
the Dograh engine contract by:
- deferring the first call creation until the engine queues the initial node
opening via ``TTSSpeakFrame`` or ``LLMContextFrame``
- returning node-transition tool results with ``responseType="new-stage"`` so
the existing call keeps its complete audio-native history
- updating the next stage's system prompt and selected tools without a
disconnect/reconnect cycle
- deferring workflow-control tools until any active Ultravox response ends
- handling Dograh-only frames such as user mute and idle append prompts
- tagging user transcripts with ``finalized=True`` for downstream parity
"""
import hashlib
import json
from typing import Any
from loguru import logger
from pydantic import Field
from websockets.exceptions import ConnectionClosed
from pipecat.frames.frames import (
Frame,
LLMMessagesAppendFrame,
TranscriptionFrame,
TTSSpeakFrame,
UserMuteStartedFrame,
UserMuteStoppedFrame,
)
from pipecat.processors.aggregators.llm_context import LLMContext, is_given
from pipecat.processors.frame_processor import FrameDirection
from pipecat.services.llm_service import LLMService
from pipecat.services.settings import _NotGiven, assert_given
from pipecat.services.ultravox.llm import (
OneShotInputParams,
UltravoxRealtimeLLMService,
websocket_client,
)
from pipecat.utils.time import time_now_iso8601
class DograhUltravoxOneShotInputParams(OneShotInputParams):
"""Dograh-friendly OneShot params with string voice support."""
voice: str | None = Field(default=None)
_ULTRAVOX_MAX_TOOL_TIMEOUT_SECS = 40.0
class DograhUltravoxRealtimeLLMService(UltravoxRealtimeLLMService):
"""Ultravox realtime with Dograh engine integration quirks."""
def __init__(self, **kwargs):
super().__init__(**kwargs)
self._context: LLMContext | None = None
self._selected_tools = None
self._user_is_muted: bool = False
self._call_started: bool = False
self._stage_update_required: bool = False
# Ultravox applies a stage update on the matching client tool result,
# so retain the provider invocation ID until that result reaches us via
# the context aggregator. Unlike Gemini, this ID is part of the wire
# protocol needed to update the existing call without reconnecting.
self._pending_node_transition_tool_call_ids: set[str] = set()
# A stage result can replace the active prompt and tools immediately.
# Hold transition invocations separately so ordinary tools can still
# run during speech while workflow control waits for response end.
self._deferred_node_transition_tool_invocations: list[
tuple[str, str, dict[str, Any]]
] = []
self._pending_user_text_messages: list[str] = []
async def start(self, frame):
# Dograh defers call creation until the engine queues the node opening.
await LLMService.start(self, frame)
async def process_frame(self, frame: Frame, direction: FrameDirection):
if isinstance(frame, UserMuteStartedFrame):
self._user_is_muted = True
await self.push_frame(frame, direction)
return
if isinstance(frame, UserMuteStoppedFrame):
self._user_is_muted = False
await self.push_frame(frame, direction)
return
if isinstance(frame, TTSSpeakFrame):
if not self._socket:
await self._connect_call(
greeting_text=frame.text,
agent_speaks_first=True,
)
else:
logger.warning(
f"{self}: TTSSpeakFrame received after the Ultravox call was "
"already created; ignoring because Ultravox owns speech output"
)
return
if isinstance(frame, LLMMessagesAppendFrame):
await self._handle_messages_append(frame)
return
await super().process_frame(frame, direction)
async def _update_settings(self, delta: UltravoxRealtimeLLMService.Settings):
changed = await super(UltravoxRealtimeLLMService, self)._update_settings(delta)
if "output_medium" in changed:
await self._update_output_medium(assert_given(self._settings.output_medium))
if "system_instruction" in changed and self._socket:
# The updated instruction is included in the native new-stage
# response when the transition tool result reaches _handle_context.
self._stage_update_required = True
handled = {"output_medium", "system_instruction"}
self._warn_unhandled_updated_settings(changed.keys() - handled)
return changed
async def _disconnect(self):
self._disconnecting = True
await self.stop_all_metrics()
if self._socket:
await self._socket.close()
self._socket = None
if self._receive_task:
await self.cancel_task(self._receive_task, timeout=1.0)
self._receive_task = None
self._completed_tool_calls = set()
self._call_started = False
self._started_placeholder_sent = set()
self._pending_node_transition_tool_call_ids = set()
self._deferred_node_transition_tool_invocations = []
self._disconnecting = False
async def _send_user_audio(self, frame):
if self._user_is_muted:
return
await super()._send_user_audio(frame)
async def _handle_context(self, context: LLMContext):
self._context = context
if not self._socket:
await self._connect_call(
greeting_text=None,
agent_speaks_first=True,
)
return
current_tools = self._current_tools_schema(context)
if self._pending_node_transition_tool_call_ids and self._tools_changed(
current_tools
):
self._stage_update_required = True
await super()._handle_context(context)
async def _handle_messages_append(self, frame: LLMMessagesAppendFrame):
texts = [
text
for text in (
self._extract_text_content(message.get("content"))
for message in frame.messages
if isinstance(message, dict)
)
if text
]
if not texts:
return
if not self._socket:
self._pending_user_text_messages.extend(texts)
await self._connect_call(
greeting_text=None,
agent_speaks_first=False,
)
return
if not self._call_started:
self._pending_user_text_messages.extend(texts)
logger.debug(
f"{self}: queueing {len(texts)} user text message(s) until call_started"
)
return
for text in texts:
await self._send_user_text(text)
async def _handle_user_transcript(self, text: str):
transcript = text.strip() if text else ""
if not transcript:
return
await self.broadcast_frame(
TranscriptionFrame,
user_id=self._last_user_id or "",
timestamp=time_now_iso8601(),
result=text,
text=transcript,
finalized=True,
)
def _requires_node_transition_context_aggregation(self) -> bool:
"""Commit any received final user transcript before changing stages.
Ultravox preserves its own audio-native history across a stage change,
but Dograh's local context still needs the final transcript before the
transition handler updates the workflow node.
"""
return True
async def _handle_tool_invocation(
self, tool_name: str, invocation_id: str, parameters: dict[str, Any]
):
if self._function_is_node_transition(tool_name):
self._pending_node_transition_tool_call_ids.add(invocation_id)
if self._bot_responding:
self._deferred_node_transition_tool_invocations.append(
(tool_name, invocation_id, parameters)
)
logger.debug(
f"{self}: deferring workflow-control call {tool_name} "
"until bot turn ends"
)
return
await super()._handle_tool_invocation(tool_name, invocation_id, parameters)
async def _handle_response_end(self):
"""Close the current response before applying queued workflow control."""
await super()._handle_response_end()
await self._run_deferred_node_transition_tool_invocations()
async def _run_deferred_node_transition_tool_invocations(self):
if not self._deferred_node_transition_tool_invocations:
return
invocations = self._deferred_node_transition_tool_invocations
self._deferred_node_transition_tool_invocations = []
logger.debug(
f"{self}: executing {len(invocations)} deferred workflow-control "
"call(s) after bot turn ended"
)
for tool_name, invocation_id, parameters in invocations:
await super()._handle_tool_invocation(
tool_name, invocation_id, parameters
)
async def _send_tool_result(self, tool_call_id: str, result: str):
is_node_transition = tool_call_id in self._pending_node_transition_tool_call_ids
try:
if is_node_transition and self._stage_update_required:
await self._send_node_transition_stage_result(tool_call_id, result)
else:
await super()._send_tool_result(tool_call_id, result)
finally:
if is_node_transition:
self._pending_node_transition_tool_call_ids.discard(tool_call_id)
async def _send_node_transition_stage_result(self, tool_call_id: str, result: str):
"""Apply node settings using Ultravox's native call-stage protocol."""
next_tools = self._current_tools_schema(self._context)
stage = {
"systemPrompt": self._current_system_instruction(),
"selectedTools": self._selected_tools_payload(next_tools),
# Keep the workflow handler's result as the tool-result message in
# the inherited conversation history for the next generation.
"toolResultText": result,
}
logger.debug(
f"{self}: updating Ultravox call stage for tool_call_id={tool_call_id} "
f"with {len(stage['selectedTools'])} selected tool(s)"
)
await self._send(
{
"type": "client_tool_result",
"invocationId": tool_call_id,
"result": json.dumps(stage, ensure_ascii=True, default=str),
"responseType": "new-stage",
}
)
self._selected_tools = next_tools
self._stage_update_required = False
async def _connect_call(
self,
*,
greeting_text: str | None,
agent_speaks_first: bool,
):
params = self._build_one_shot_params(
greeting_text=greeting_text,
agent_speaks_first=agent_speaks_first,
)
self._params = params
self._selected_tools = self._current_tools_schema(self._context)
tool_names = (
[tool.name for tool in self._selected_tools.standard_tools]
if self._selected_tools
else []
)
prompt = params.system_prompt or ""
prompt_hash = hashlib.sha256(prompt.encode("utf-8")).hexdigest()[:12]
try:
logger.info(
f"{self}: creating Ultravox call "
f"(agent_speaks_first={agent_speaks_first}, "
f"voice={params.voice!r}, "
f"tools={tool_names}, "
f"system_prompt_len={len(prompt)}, "
f"system_prompt_sha256={prompt_hash})"
)
join_url = await self._start_one_shot_call(params)
logger.info(f"Joining Ultravox Realtime call via URL: {join_url}")
self._socket = await websocket_client.connect(join_url)
self._receive_task = self.create_task(self._receive_messages())
self._call_started = False
except Exception as e:
logger.error(
f"{self}: Ultravox call creation/join failed "
f"for tools={tool_names}: {e}"
)
await self.push_error(f"Failed to connect to Ultravox: {e}", e, fatal=True)
async def _receive_messages(self):
"""Receive messages from the Ultravox Realtime WebSocket.
Upstream handles exceptions raised while processing individual messages,
but websocket close exceptions are raised by the async iterator itself.
During user hangup / pipeline teardown that close is expected, so treat
normal websocket shutdown as a debug condition rather than a pipeline
error.
"""
if not self._socket:
return
try:
async for message in self._socket:
try:
if isinstance(message, bytes):
await self._handle_audio(message)
continue
data = json.loads(message)
match data.get("type"):
case "call_started":
self._call_started = True
logger.debug(
f"{self}: Ultravox call_started received for callId="
f"{data.get('callId')}"
)
await self._flush_pending_user_text_messages()
case "state":
if self._bot_responding and data.get("state") != "speaking":
await self._handle_response_end()
case "client_tool_invocation":
await self._handle_tool_invocation(
data.get("toolName"),
data.get("invocationId"),
data.get("parameters"),
)
case "transcript":
match data.get("role"):
case "user":
if not data.get("final"):
logger.warning(
"Unexpected non-final user transcript from Ultravox Realtime; ignoring."
)
else:
await self._handle_user_transcript(
data.get("text")
)
case "agent":
await self._handle_agent_transcript(
data.get("medium"),
data.get("text"),
data.get("delta"),
data.get("final", False),
)
case _:
logger.debug(
f"Received transcript with unknown role from Ultravox Realtime: {data}"
)
case _:
logger.debug(f"Received unhandled Ultravox message: {data}")
except Exception as e:
if self._disconnecting or not self._socket:
return
await self.push_error(
"Ultravox websocket receive error", e, fatal=True
)
except ConnectionClosed as e:
if (
self._disconnecting
or not self._socket
or self._is_benign_websocket_close(e)
):
logger.debug(f"{self}: Ultravox websocket closed: {e}")
return
await self.push_error("Ultravox websocket receive error", e, fatal=True)
async def _flush_pending_user_text_messages(self):
if (
not self._socket
or not self._call_started
or not self._pending_user_text_messages
):
return
pending_texts = self._pending_user_text_messages
self._pending_user_text_messages = []
for pending_text in pending_texts:
await self._send_user_text(pending_text)
def _build_one_shot_params(
self,
*,
greeting_text: str | None,
agent_speaks_first: bool,
) -> DograhUltravoxOneShotInputParams:
current_params = self._params
extra = {
key: value
for key, value in current_params.extra.items()
if key != "firstSpeakerSettings"
}
if greeting_text is not None:
extra["firstSpeakerSettings"] = {"agent": {"text": greeting_text}}
elif agent_speaks_first:
extra["firstSpeakerSettings"] = {"agent": {}}
else:
extra["firstSpeakerSettings"] = {"user": {}}
output_medium = self._settings.output_medium
if isinstance(output_medium, _NotGiven):
output_medium = current_params.output_medium
return DograhUltravoxOneShotInputParams(
api_key=current_params.api_key,
system_prompt=self._current_system_instruction(),
temperature=current_params.temperature,
model=assert_given(self._settings.model),
voice=current_params.voice,
metadata=current_params.metadata,
output_medium=output_medium,
max_duration=current_params.max_duration,
extra=extra,
)
def _current_tools_schema(self, context: LLMContext | None):
if context is None or not is_given(context.tools):
return None
return context.tools
def _selected_tools_payload(self, tools: Any) -> list[dict[str, Any]]:
return self._to_selected_tools(tools) if tools else []
def _tools_changed(self, tools: Any) -> bool:
return self._selected_tools_payload(tools) != self._selected_tools_payload(
self._selected_tools
)
def _to_selected_tools(self, tool: Any) -> list[dict[str, Any]]:
selected_tools = super()._to_selected_tools(tool)
for selected_tool in selected_tools:
temporary_tool = selected_tool.get("temporaryTool")
if not isinstance(temporary_tool, dict):
continue
tool_name = temporary_tool.get("modelToolName")
if not isinstance(tool_name, str):
continue
timeout = self._ultravox_timeout_for_tool(tool_name)
if timeout is not None:
temporary_tool["timeout"] = timeout
return selected_tools
def _current_system_instruction(self) -> str | None:
system_instruction = self._settings.system_instruction
if isinstance(system_instruction, _NotGiven):
return None
return system_instruction
def _ultravox_timeout_for_tool(self, function_name: str) -> str | None:
item = self._functions.get(function_name) or self._functions.get(None)
if item is None or item.timeout_secs is None or item.timeout_secs <= 0:
return None
timeout_secs = min(float(item.timeout_secs), _ULTRAVOX_MAX_TOOL_TIMEOUT_SECS)
return f"{timeout_secs:g}s"
@staticmethod
def _is_benign_websocket_close(exc: ConnectionClosed) -> bool:
return any(
close is not None and close.code in {1000, 1001}
for close in (exc.sent, exc.rcvd)
)
@staticmethod
def _extract_text_content(content: Any) -> str | None:
if isinstance(content, str):
return content
if isinstance(content, list):
parts: list[str] = []
for part in content:
if not isinstance(part, dict):
return None
if part.get("type") != "text":
return None
text = part.get("text")
if not isinstance(text, str):
return None
parts.append(text)
return "\n".join(parts) if parts else None
return None