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chatkit-python/chatkit

chatkit/server.py

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1import asyncio
2from abc import ABC, abstractmethod
3from collections.abc import AsyncIterator
4from contextlib import contextmanager
5from datetime import datetime
6from typing import (
7 Any,
8 AsyncGenerator,
9 AsyncIterable,
10 Callable,
11 Generic,
12)
13
14import agents
15from agents.models.chatcmpl_helpers import (
16 HEADERS_OVERRIDE as chat_completions_headers_override,
17)
18from agents.models.openai_responses import (
19 _HEADERS_OVERRIDE as responses_headers_override,
20)
21from pydantic import BaseModel, TypeAdapter
22from typing_extensions import TypeVar, assert_never
23
24from chatkit.errors import CustomStreamError, StreamError
25
26from .logger import logger
27from .store import AttachmentStore, Store, StoreItemType, default_generate_id
28from .types import (
29 Action,
30 AssistantMessageContent,
31 AssistantMessageContentPartAdded,
32 AssistantMessageContentPartAnnotationAdded,
33 AssistantMessageContentPartDone,
34 AssistantMessageContentPartTextDelta,
35 AssistantMessageItem,
36 AttachmentsCreateReq,
37 AttachmentsDeleteReq,
38 ChatKitReq,
39 ClientToolCallItem,
40 ErrorCode,
41 ErrorEvent,
42 FeedbackKind,
43 HiddenContextItem,
44 ItemsFeedbackReq,
45 ItemsListReq,
46 NonStreamingReq,
47 Page,
48 SDKHiddenContextItem,
49 StreamingReq,
50 StreamOptions,
51 StreamOptionsEvent,
52 Thread,
53 ThreadCreatedEvent,
54 ThreadItem,
55 ThreadItemAddedEvent,
56 ThreadItemDoneEvent,
57 ThreadItemRemovedEvent,
58 ThreadItemReplacedEvent,
59 ThreadItemUpdatedEvent,
60 ThreadMetadata,
61 ThreadsAddClientToolOutputReq,
62 ThreadsAddUserMessageReq,
63 ThreadsCreateReq,
64 ThreadsCustomActionReq,
65 ThreadsDeleteReq,
66 ThreadsGetByIdReq,
67 ThreadsListReq,
68 ThreadsRetryAfterItemReq,
69 ThreadStreamEvent,
70 ThreadsUpdateReq,
71 ThreadUpdatedEvent,
72 UserMessageInput,
73 UserMessageItem,
74 WidgetComponentUpdated,
75 WidgetItem,
76 WidgetRootUpdated,
77 WidgetStreamingTextValueDelta,
78 WorkflowItem,
79 WorkflowTaskAdded,
80 WorkflowTaskUpdated,
81 is_streaming_req,
82)
83from .version import __version__
84from .widgets import WidgetComponent, WidgetComponentBase, WidgetRoot
85
86DEFAULT_PAGE_SIZE = 20
87DEFAULT_ERROR_MESSAGE = "An error occurred when generating a response."
88
89
90def diff_widget(
91 before: WidgetRoot, after: WidgetRoot
92) -> list[WidgetStreamingTextValueDelta | WidgetRootUpdated | WidgetComponentUpdated]:
93 """
94 Compare two WidgetRoots and return a list of deltas.
95 """
96
97 def is_streaming_text(component: WidgetComponentBase) -> bool:
98 return getattr(component, "type", None) in {"Markdown", "Text"} and isinstance(
99 getattr(component, "value", None), str
100 )
101
102 def full_replace(before: WidgetComponentBase, after: WidgetComponentBase) -> bool:
103 if (
104 before.type != after.type
105 or before.id != after.id
106 or before.key != after.key
107 ):
108 return True
109
110 def full_replace_value(before_value: Any, after_value: Any) -> bool:
111 if isinstance(before_value, list) and isinstance(after_value, list):
112 if len(before_value) != len(after_value):
113 return True
114 for nth_before_value, nth_after_value in zip(before_value, after_value):
115 if full_replace_value(nth_before_value, nth_after_value):
116 return True
117 elif before_value != after_value:
118 if isinstance(before_value, WidgetComponentBase) and isinstance(
119 after_value, WidgetComponentBase
120 ):
121 return full_replace(before_value, after_value)
122 else:
123 return True
124 return False
125
126 for field in before.model_fields_set.union(after.model_fields_set):
127 if (
128 is_streaming_text(before)
129 and is_streaming_text(after)
130 and field == "value"
131 and getattr(after, "value", "").startswith(getattr(before, "value", ""))
132 ):
133 # Appends to the value prop of Markdown or Text do not trigger a full replace
134 continue
135 if full_replace_value(getattr(before, field), getattr(after, field)):
136 return True
137
138 return False
139
140 if full_replace(before, after):
141 return [WidgetRootUpdated(widget=after)]
142
143 deltas: list[
144 WidgetStreamingTextValueDelta | WidgetComponentUpdated | WidgetRootUpdated
145 ] = []
146
147 def find_all_streaming_text_components(
148 component: WidgetComponent | WidgetRoot,
149 ) -> dict[str, WidgetComponentBase]:
150 components = {}
151
152 def recurse(component: WidgetComponent | WidgetRoot):
153 if is_streaming_text(component) and component.id:
154 components[component.id] = component
155
156 if hasattr(component, "children"):
157 children = getattr(component, "children", None) or []
158 for child in children:
159 recurse(child)
160
161 recurse(component)
162 return components
163
164 before_nodes = find_all_streaming_text_components(before)
165 after_nodes = find_all_streaming_text_components(after)
166
167 for id, after_node in after_nodes.items():
168 before_node = before_nodes.get(id)
169 if before_node is None:
170 raise ValueError(
171 f"Node {id} was not present when the widget was initially rendered. All nodes with ID must persist across all widget updates."
172 )
173
174 before_value = str(getattr(before_node, "value", None))
175 after_value = str(getattr(after_node, "value", None))
176
177 if before_value != after_value:
178 if not after_value.startswith(before_value):
179 raise ValueError(
180 f"Node {id} was updated with a new value that is not a prefix of the initial value. All widget updates must be cumulative."
181 )
182 done = not getattr(after_node, "streaming", False)
183 deltas.append(
184 WidgetStreamingTextValueDelta(
185 component_id=id,
186 delta=after_value[len(before_value) :],
187 done=done,
188 )
189 )
190
191 return deltas
192
193
194async def stream_widget(
195 thread: ThreadMetadata,
196 widget: WidgetRoot | AsyncGenerator[WidgetRoot, None],
197 copy_text: str | None = None,
198 generate_id: Callable[[StoreItemType], str] = default_generate_id,
199) -> AsyncIterator[ThreadStreamEvent]:
200 """Stream a widget root (or async sequence of roots) as ThreadStreamEvents."""
201 item_id = generate_id("message")
202
203 if not isinstance(widget, AsyncGenerator):
204 yield ThreadItemDoneEvent(
205 item=WidgetItem(
206 id=item_id,
207 thread_id=thread.id,
208 created_at=datetime.now(),
209 widget=widget,
210 copy_text=copy_text,
211 ),
212 )
213 return
214
215 initial_state = await widget.__anext__()
216
217 item = WidgetItem(
218 id=item_id,
219 created_at=datetime.now(),
220 widget=initial_state,
221 copy_text=copy_text,
222 thread_id=thread.id,
223 )
224
225 yield ThreadItemAddedEvent(item=item)
226
227 last_state = initial_state
228
229 while widget:
230 try:
231 new_state = await widget.__anext__()
232 for update in diff_widget(last_state, new_state):
233 yield ThreadItemUpdatedEvent(
234 item_id=item_id,
235 update=update,
236 )
237 last_state = new_state
238 except StopAsyncIteration:
239 break
240
241 yield ThreadItemDoneEvent(
242 item=item.model_copy(update={"widget": last_state}),
243 )
244
245
246@contextmanager
247def agents_sdk_user_agent_override():
248 ua = f"Agents/Python {agents.__version__} ChatKit/Python {__version__}"
249 chat_completions_token = chat_completions_headers_override.set({"User-Agent": ua})
250 responses_token = responses_headers_override.set({"User-Agent": ua})
251
252 yield
253
254 chat_completions_headers_override.reset(chat_completions_token)
255 responses_headers_override.reset(responses_token)
256
257
258class StreamingResult(AsyncIterable[bytes]):
259 def __init__(self, stream: AsyncGenerator[bytes, None]):
260 self.json_events = stream
261
262 async def __aiter__(self):
263 async for event in self.json_events:
264 yield event
265
266
267class NonStreamingResult:
268 def __init__(self, result: bytes):
269 self.json = result
270
271
272TContext = TypeVar("TContext", default=Any)
273
274
275class ChatKitServer(ABC, Generic[TContext]):
276 def __init__(
277 self,
278 store: Store[TContext],
279 attachment_store: AttachmentStore[TContext] | None = None,
280 ):
281 """Create a ChatKitServer with the backing Store and optional AttachmentStore."""
282 self.store = store
283 self.attachment_store = attachment_store
284
285 def _get_attachment_store(self) -> AttachmentStore[TContext]:
286 """Return the configured AttachmentStore or raise if missing."""
287 if self.attachment_store is None:
288 raise RuntimeError(
289 "AttachmentStore is not configured. Provide a AttachmentStore to ChatKitServer to handle file operations."
290 )
291 return self.attachment_store
292
293 @abstractmethod
294 def respond(
295 self,
296 thread: ThreadMetadata,
297 input_user_message: UserMessageItem | None,
298 context: TContext,
299 ) -> AsyncIterator[ThreadStreamEvent]:
300 """Stream `ThreadStreamEvent` instances for a new user message.
301
302 Args:
303 thread: Metadata for the thread being processed.
304 input_user_message: The incoming message the server should respond to, if any.
305 context: Arbitrary per-request context provided by the caller.
306
307 Returns:
308 An async iterator that yields events representing the server's response.
309 """
310 pass
311
312 async def add_feedback( # noqa: B027
313 self,
314 thread_id: str,
315 item_ids: list[str],
316 feedback: FeedbackKind,
317 context: TContext,
318 ) -> None:
319 """Persist user feedback for one or more thread items."""
320 pass
321
322 def action(
323 self,
324 thread: ThreadMetadata,
325 action: Action[str, Any],
326 sender: WidgetItem | None,
327 context: TContext,
328 ) -> AsyncIterator[ThreadStreamEvent]:
329 """Handle a widget or client-dispatched action and yield response events."""
330 raise NotImplementedError(
331 "The action() method must be overridden to react to actions. "
332 "See https://github.com/openai/chatkit-python/blob/main/docs/widgets.md#widget-actions"
333 )
334
335 def get_stream_options(
336 self, thread: ThreadMetadata, context: TContext
337 ) -> StreamOptions:
338 """
339 Return stream-level runtime options. Allows the user to cancel the stream by default.
340 Override this method to customize behavior.
341 """
342 return StreamOptions(allow_cancel=True)
343
344 async def handle_stream_cancelled(
345 self,
346 thread: ThreadMetadata,
347 pending_items: list[ThreadItem],
348 context: TContext,
349 ):
350 """Perform custom cleanup / stop inference when a stream is cancelled.
351 Updates you make here will not be reflected in the UI until a reload.
352
353 The default implementation persists any non-empty pending assistant messages
354 to the thread but does not auto-save pending widget items or workflow items.
355
356 Args:
357 thread: The thread that was being processed.
358 pending_items: Items that were not done streaming at cancellation time.
359 context: Arbitrary per-request context provided by the caller.
360 """
361 pending_assistant_message_items: list[AssistantMessageItem] = [
362 item for item in pending_items if isinstance(item, AssistantMessageItem)
363 ]
364 for item in pending_assistant_message_items:
365 is_empty = len(item.content) == 0 or all(
366 (not content.text.strip()) for content in item.content
367 )
368 if not is_empty:
369 await self.store.add_thread_item(thread.id, item, context=context)
370
371 # Add a hidden context item to the thread to indicate that the stream was cancelled.
372 # Otherwise, depending on the timing of the cancellation, subsequent responses may
373 # attempt to continue the cancelled response.
374 await self.store.add_thread_item(
375 thread.id,
376 SDKHiddenContextItem(
377 thread_id=thread.id,
378 created_at=datetime.now(),
379 id=self.store.generate_item_id("sdk_hidden_context", thread, context),
380 content="The user cancelled the stream. Stop responding to the prior request.",
381 ),
382 context=context,
383 )
384
385 async def process(
386 self, request: str | bytes | bytearray, context: TContext
387 ) -> StreamingResult | NonStreamingResult:
388 """Parse an incoming ChatKit request and route it to streaming or non-streaming handlers."""
389 parsed_request = TypeAdapter[ChatKitReq](ChatKitReq).validate_json(request)
390 logger.info(f"Received request op: {parsed_request.type}")
391
392 if is_streaming_req(parsed_request):
393 return StreamingResult(self._process_streaming(parsed_request, context))
394 else:
395 return NonStreamingResult(
396 await self._process_non_streaming(parsed_request, context)
397 )
398
399 async def _process_non_streaming(
400 self, request: NonStreamingReq, context: TContext
401 ) -> bytes:
402 match request:
403 case ThreadsGetByIdReq():
404 thread = await self._load_full_thread(
405 request.params.thread_id, context=context
406 )
407 return self._serialize(self._to_thread_response(thread))
408 case ThreadsListReq():
409 params = request.params
410 threads = await self.store.load_threads(
411 limit=params.limit or DEFAULT_PAGE_SIZE,
412 after=params.after,
413 order=params.order,
414 context=context,
415 )
416 return self._serialize(
417 Page(
418 has_more=threads.has_more,
419 after=threads.after,
420 data=[
421 self._to_thread_response(thread) for thread in threads.data
422 ],
423 )
424 )
425 case ItemsFeedbackReq():
426 await self.add_feedback(
427 request.params.thread_id,
428 request.params.item_ids,
429 request.params.kind,
430 context,
431 )
432 return b"{}"
433 case AttachmentsCreateReq():
434 attachment_store = self._get_attachment_store()
435 attachment = await attachment_store.create_attachment(
436 request.params, context
437 )
438 return self._serialize(attachment)
439 case AttachmentsDeleteReq():
440 attachment_store = self._get_attachment_store()
441 await attachment_store.delete_attachment(
442 request.params.attachment_id, context=context
443 )
444 await self.store.delete_attachment(
445 request.params.attachment_id, context=context
446 )
447 return b"{}"
448 case ItemsListReq():
449 items_list_params = request.params
450 items = await self.store.load_thread_items(
451 items_list_params.thread_id,
452 limit=items_list_params.limit or DEFAULT_PAGE_SIZE,
453 order=items_list_params.order,
454 after=items_list_params.after,
455 context=context,
456 )
457 # filter out hidden context items
458 items.data = [
459 item
460 for item in items.data
461 if not isinstance(item, (HiddenContextItem, SDKHiddenContextItem))
462 ]
463 return self._serialize(items)
464 case ThreadsUpdateReq():
465 thread = await self.store.load_thread(
466 request.params.thread_id, context=context
467 )
468 thread.title = request.params.title
469 await self.store.save_thread(thread, context=context)
470 return self._serialize(self._to_thread_response(thread))
471 case ThreadsDeleteReq():
472 await self.store.delete_thread(
473 request.params.thread_id, context=context
474 )
475 return b"{}"
476 case _:
477 assert_never(request)
478
479 async def _process_streaming(
480 self, request: StreamingReq, context: TContext
481 ) -> AsyncGenerator[bytes, None]:
482 try:
483 async for event in self._process_streaming_impl(request, context):
484 b = self._serialize(event)
485 yield b"data: " + b + b"\n\n"
486 except asyncio.CancelledError:
487 # Let cancellation bubble up without logging as an error.
488 raise
489 except Exception:
490 logger.exception("Error while generating streamed response")
491 raise
492
493 async def _process_streaming_impl(
494 self, request: StreamingReq, context: TContext
495 ) -> AsyncGenerator[ThreadStreamEvent, None]:
496 match request:
497 case ThreadsCreateReq():
498 thread = Thread(
499 id=self.store.generate_thread_id(context),
500 created_at=datetime.now(),
501 items=Page(),
502 )
503 await self.store.save_thread(
504 ThreadMetadata(**thread.model_dump()),
505 context=context,
506 )
507 yield ThreadCreatedEvent(thread=self._to_thread_response(thread))
508 user_message = await self._build_user_message_item(
509 request.params.input, thread, context
510 )
511 async for event in self._process_new_thread_item_respond(
512 thread,
513 user_message,
514 context,
515 ):
516 yield event
517
518 case ThreadsAddUserMessageReq():
519 thread = await self.store.load_thread(
520 request.params.thread_id, context=context
521 )
522 user_message = await self._build_user_message_item(
523 request.params.input, thread, context
524 )
525 async for event in self._process_new_thread_item_respond(
526 thread,
527 user_message,
528 context,
529 ):
530 yield event
531
532 case ThreadsAddClientToolOutputReq():
533 thread = await self.store.load_thread(
534 request.params.thread_id, context=context
535 )
536 items = await self.store.load_thread_items(
537 thread.id, None, 1, "desc", context
538 )
539 tool_call = next(
540 (
541 item
542 for item in items.data
543 if isinstance(item, ClientToolCallItem)
544 and item.status == "pending"
545 ),
546 None,
547 )
548 if not tool_call:
549 raise ValueError(
550 f"Last thread item in {thread.id} was not a ClientToolCallItem"
551 )
552
553 tool_call.output = request.params.result
554 tool_call.status = "completed"
555
556 await self.store.save_item(thread.id, tool_call, context=context)
557
558 # Safety against dangling pending tool calls if there are
559 # multiple in a row, which should be impossible, and
560 # integrations should ultimately filter out pending tool calls
561 # when creating input response messages.
562 await self._cleanup_pending_client_tool_call(thread, context)
563
564 async for event in self._process_events(
565 thread,
566 context,
567 lambda: self.respond(thread, None, context),
568 ):
569 yield event
570
571 case ThreadsRetryAfterItemReq():
572 thread_metadata = await self.store.load_thread(
573 request.params.thread_id, context=context
574 )
575
576 # Collect items to remove (all items after the user message)
577 items_to_remove: list[ThreadItem] = []
578 user_message_item = None
579
580 async for item in self._paginate_thread_items_reverse(
581 request.params.thread_id, context
582 ):
583 if item.id == request.params.item_id:
584 if not isinstance(item, UserMessageItem):
585 raise ValueError(
586 f"Item {request.params.item_id} is not a user message"
587 )
588 user_message_item = item
589 break
590 items_to_remove.append(item)
591
592 if user_message_item:
593 for item in items_to_remove:
594 await self.store.delete_thread_item(
595 request.params.thread_id, item.id, context=context
596 )
597 async for event in self._process_events(
598 thread_metadata,
599 context,
600 lambda: self.respond(
601 thread_metadata,
602 user_message_item,
603 context,
604 ),
605 ):
606 yield event
607 case ThreadsCustomActionReq():
608 thread_metadata = await self.store.load_thread(
609 request.params.thread_id, context=context
610 )
611
612 item: ThreadItem | None = None
613 if request.params.item_id:
614 item = await self.store.load_item(
615 request.params.thread_id,
616 request.params.item_id,
617 context=context,
618 )
619
620 if item and not isinstance(item, WidgetItem):
621 # shouldn't happen if the caller is using the API correctly.
622 yield ErrorEvent(
623 code=ErrorCode.STREAM_ERROR,
624 allow_retry=False,
625 )
626 return
627
628 async for event in self._process_events(
629 thread_metadata,
630 context,
631 lambda: self.action(
632 thread_metadata,
633 request.params.action,
634 item,
635 context,
636 ),
637 ):
638 yield event
639
640 case _:
641 assert_never(request)
642
643 async def _cleanup_pending_client_tool_call(
644 self, thread: ThreadMetadata, context: TContext
645 ) -> None:
646 items = await self.store.load_thread_items(
647 thread.id, None, DEFAULT_PAGE_SIZE, "desc", context
648 )
649 for tool_call in items.data:
650 if not isinstance(tool_call, ClientToolCallItem):
651 continue
652 if tool_call.status == "pending":
653 logger.warning(
654 f"Client tool call {tool_call.call_id} was not completed, ignoring"
655 )
656 await self.store.delete_thread_item(
657 thread.id, tool_call.id, context=context
658 )
659
660 async def _process_new_thread_item_respond(
661 self,
662 thread: ThreadMetadata,
663 item: UserMessageItem,
664 context: TContext,
665 ) -> AsyncIterator[ThreadStreamEvent]:
666 await self.store.add_thread_item(thread.id, item, context=context)
667 await self._cleanup_pending_client_tool_call(thread, context)
668 yield ThreadItemDoneEvent(item=item)
669
670 async for event in self._process_events(
671 thread,
672 context,
673 lambda: self.respond(thread, item, context),
674 ):
675 yield event
676
677 async def _process_events(
678 self,
679 thread: ThreadMetadata,
680 context: TContext,
681 stream: Callable[[], AsyncIterator[ThreadStreamEvent]],
682 ) -> AsyncIterator[ThreadStreamEvent]:
683 await asyncio.sleep(0) # allow the response to start streaming
684
685 # Send initial stream options
686 yield StreamOptionsEvent(
687 stream_options=self.get_stream_options(thread, context)
688 )
689
690 last_thread = thread.model_copy(deep=True)
691
692 # Keep track of items that were streamed but not yet saved
693 # so that we can persist them when the stream is cancelled.
694 pending_items: dict[str, ThreadItem] = {}
695
696 try:
697 with agents_sdk_user_agent_override():
698 async for event in stream():
699 if isinstance(event, ThreadItemAddedEvent):
700 pending_items[event.item.id] = event.item
701
702 match event:
703 case ThreadItemDoneEvent():
704 await self.store.add_thread_item(
705 thread.id, event.item, context=context
706 )
707 pending_items.pop(event.item.id, None)
708 case ThreadItemRemovedEvent():
709 await self.store.delete_thread_item(
710 thread.id, event.item_id, context=context
711 )
712 pending_items.pop(event.item_id, None)
713 case ThreadItemReplacedEvent():
714 await self.store.save_item(
715 thread.id, event.item, context=context
716 )
717 pending_items.pop(event.item.id, None)
718 case ThreadItemUpdatedEvent():
719 # Keep pending assistant message and workflow items up to date
720 # so that we have a reference to the latest version of these pending items
721 # when the stream is cancelled.
722 self._update_pending_items(pending_items, event)
723
724 # special case - don't send hidden context items back to the client
725 should_swallow_event = isinstance(
726 event, ThreadItemDoneEvent
727 ) and isinstance(
728 event.item, (HiddenContextItem, SDKHiddenContextItem)
729 )
730
731 if not should_swallow_event:
732 yield event
733
734 # in case user updated the thread while streaming
735 if thread != last_thread:
736 last_thread = thread.model_copy(deep=True)
737 await self.store.save_thread(thread, context=context)
738 yield ThreadUpdatedEvent(
739 thread=self._to_thread_response(thread)
740 )
741 # in case user updated the thread while streaming
742 if thread != last_thread:
743 last_thread = thread.model_copy(deep=True)
744 await self.store.save_thread(thread, context=context)
745 yield ThreadUpdatedEvent(thread=self._to_thread_response(thread))
746 except asyncio.CancelledError:
747 await self.handle_stream_cancelled(
748 thread, list(pending_items.values()), context
749 )
750 raise
751 except CustomStreamError as e:
752 yield ErrorEvent(
753 code="custom",
754 message=e.message,
755 allow_retry=e.allow_retry,
756 )
757 except StreamError as e:
758 yield ErrorEvent(
759 code=e.code,
760 allow_retry=e.allow_retry,
761 )
762 except Exception as e:
763 yield ErrorEvent(
764 code=ErrorCode.STREAM_ERROR,
765 allow_retry=True,
766 )
767 logger.exception(e)
768
769 if thread != last_thread:
770 # in case user updated the thread at the end of the stream
771 await self.store.save_thread(thread, context=context)
772 yield ThreadUpdatedEvent(thread=self._to_thread_response(thread))
773
774 def _apply_assistant_message_update(
775 self,
776 item: AssistantMessageItem,
777 update: AssistantMessageContentPartAdded
778 | AssistantMessageContentPartTextDelta
779 | AssistantMessageContentPartAnnotationAdded
780 | AssistantMessageContentPartDone,
781 ) -> AssistantMessageItem:
782 updated = item.model_copy(deep=True)
783
784 # Pad the content list so the requested content_index exists before we write into it.
785 # (Streaming updates can arrive for an index that hasn’t been created yet)
786 while len(updated.content) <= update.content_index:
787 updated.content.append(AssistantMessageContent(text="", annotations=[]))
788
789 match update:
790 case AssistantMessageContentPartAdded():
791 updated.content[update.content_index] = update.content
792 case AssistantMessageContentPartTextDelta():
793 updated.content[update.content_index].text += update.delta
794 case AssistantMessageContentPartAnnotationAdded():
795 annotations = updated.content[update.content_index].annotations
796 if update.annotation_index <= len(annotations):
797 annotations.insert(update.annotation_index, update.annotation)
798 else:
799 annotations.append(update.annotation)
800 case AssistantMessageContentPartDone():
801 updated.content[update.content_index] = update.content
802 return updated
803
804 def _update_pending_items(
805 self,
806 pending_items: dict[str, ThreadItem],
807 event: ThreadItemUpdatedEvent,
808 ):
809 updated_item = pending_items.get(event.item_id)
810 update = event.update
811 match updated_item:
812 case AssistantMessageItem():
813 if isinstance(
814 update,
815 (
816 AssistantMessageContentPartAdded,
817 AssistantMessageContentPartTextDelta,
818 AssistantMessageContentPartAnnotationAdded,
819 AssistantMessageContentPartDone,
820 ),
821 ):
822 pending_items[updated_item.id] = (
823 self._apply_assistant_message_update(updated_item, update)
824 )
825 case WorkflowItem():
826 if isinstance(update, (WorkflowTaskUpdated, WorkflowTaskAdded)):
827 match update:
828 case WorkflowTaskUpdated():
829 updated_item.workflow.tasks[update.task_index] = update.task
830 case WorkflowTaskAdded():
831 updated_item.workflow.tasks.append(update.task)
832
833 pending_items[updated_item.id] = updated_item
834 case _:
835 pass
836
837 async def _build_user_message_item(
838 self, input: UserMessageInput, thread: ThreadMetadata, context: TContext
839 ) -> UserMessageItem:
840 return UserMessageItem(
841 id=self.store.generate_item_id("message", thread, context),
842 content=input.content,
843 thread_id=thread.id,
844 attachments=[
845 await self.store.load_attachment(attachment_id, context)
846 for attachment_id in input.attachments
847 ],
848 quoted_text=input.quoted_text,
849 inference_options=input.inference_options,
850 created_at=datetime.now(),
851 )
852
853 async def _load_full_thread(self, thread_id: str, context: TContext) -> Thread:
854 thread_meta = await self.store.load_thread(thread_id, context=context)
855 thread_items = await self.store.load_thread_items(
856 thread_id,
857 after=None,
858 limit=DEFAULT_PAGE_SIZE,
859 order="asc",
860 context=context,
861 )
862 return Thread(**thread_meta.model_dump(), items=thread_items)
863
864 async def _paginate_thread_items_reverse(
865 self, thread_id: str, context: TContext
866 ) -> AsyncIterator[ThreadItem]:
867 """Paginate through thread items in reverse order (newest first)."""
868 after = None
869 while True:
870 items = await self.store.load_thread_items(
871 thread_id, after, DEFAULT_PAGE_SIZE, "desc", context
872 )
873 for item in items.data:
874 yield item
875
876 if not items.has_more:
877 break
878 after = items.after
879
880 def _serialize(self, obj: BaseModel) -> bytes:
881 return obj.model_dump_json(by_alias=True, exclude_none=True).encode("utf-8")
882
883 def _to_thread_response(self, thread: ThreadMetadata | Thread) -> Thread:
884 def is_hidden(item: ThreadItem) -> bool:
885 return isinstance(item, (HiddenContextItem, SDKHiddenContextItem))
886
887 items = thread.items if isinstance(thread, Thread) else Page()
888 items.data = [item for item in items.data if not is_hidden(item)]
889
890 return Thread(
891 id=thread.id,
892 title=thread.title,
893 created_at=thread.created_at,
894 items=items,
895 status=thread.status,
896 )