feat(agent): default to message 'ts' when no 'thread_ts' is avaialble for 'agent.chat_stream(...)' (#1444)

Co-authored-by: Ale Mercado <maria.mercado@slack-corp.com>

Author: zimeg

slack_bolt/agent/agent.py

@@ -11,9 +11,6 @@ class BoltAgent:
     Experimental:
         This API is experimental and may change in future releases.
 
-        FIXME: chat_stream() only works when thread_ts is available (DMs and threaded replies).
-        It does not work on channel messages because ts is not provided to BoltAgent yet.
-
         @app.event("app_mention")
         def handle_mention(agent):
             stream = agent.chat_stream()
@@ -27,12 +24,14 @@ def __init__(
         client: WebClient,
         channel_id: Optional[str] = None,
         thread_ts: Optional[str] = None,
+        ts: Optional[str] = None,
         team_id: Optional[str] = None,
         user_id: Optional[str] = None,
     ):
         self._client = client
         self._channel_id = channel_id
         self._thread_ts = thread_ts
+        self._ts = ts
         self._team_id = team_id
         self._user_id = user_id
 
@@ -67,7 +66,7 @@ def chat_stream(
         # Argument validation is delegated to chat_stream() and the API
         return self._client.chat_stream(
             channel=channel or self._channel_id,  # type: ignore[arg-type]
-            thread_ts=thread_ts or self._thread_ts,  # type: ignore[arg-type]
+            thread_ts=thread_ts or self._thread_ts or self._ts,  # type: ignore[arg-type]
             recipient_team_id=recipient_team_id or self._team_id,
             recipient_user_id=recipient_user_id or self._user_id,
             **kwargs,
@@ -96,7 +95,7 @@ def set_status(
         """
         return self._client.assistant_threads_setStatus(
             channel_id=channel or self._channel_id,  # type: ignore[arg-type]
-            thread_ts=thread_ts or self._thread_ts,  # type: ignore[arg-type]
+            thread_ts=thread_ts or self._thread_ts or self._ts,  # type: ignore[arg-type]
             status=status,
             loading_messages=loading_messages,
             **kwargs,
@@ -133,7 +132,7 @@ def set_suggested_prompts(
 
         return self._client.assistant_threads_setSuggestedPrompts(
             channel_id=channel or self._channel_id,  # type: ignore[arg-type]
-            thread_ts=thread_ts or self._thread_ts,  # type: ignore[arg-type]
+            thread_ts=thread_ts or self._thread_ts or self._ts,  # type: ignore[arg-type]
             prompts=prompts_arg,
             title=title,
             **kwargs,

slack_bolt/agent/async_agent.py

@@ -23,12 +23,14 @@ def __init__(
         client: AsyncWebClient,
         channel_id: Optional[str] = None,
         thread_ts: Optional[str] = None,
+        ts: Optional[str] = None,
         team_id: Optional[str] = None,
         user_id: Optional[str] = None,
     ):
         self._client = client
         self._channel_id = channel_id
         self._thread_ts = thread_ts
+        self._ts = ts
         self._team_id = team_id
         self._user_id = user_id
 
@@ -63,7 +65,7 @@ async def chat_stream(
         # Argument validation is delegated to chat_stream() and the API
         return await self._client.chat_stream(
             channel=channel or self._channel_id,  # type: ignore[arg-type]
-            thread_ts=thread_ts or self._thread_ts,  # type: ignore[arg-type]
+            thread_ts=thread_ts or self._thread_ts or self._ts,  # type: ignore[arg-type]
             recipient_team_id=recipient_team_id or self._team_id,
             recipient_user_id=recipient_user_id or self._user_id,
             **kwargs,
@@ -92,7 +94,7 @@ async def set_status(
         """
         return await self._client.assistant_threads_setStatus(
             channel_id=channel or self._channel_id,  # type: ignore[arg-type]
-            thread_ts=thread_ts or self._thread_ts,  # type: ignore[arg-type]
+            thread_ts=thread_ts or self._thread_ts or self._ts,  # type: ignore[arg-type]
             status=status,
             loading_messages=loading_messages,
             **kwargs,
@@ -129,7 +131,7 @@ async def set_suggested_prompts(
 
         return await self._client.assistant_threads_setSuggestedPrompts(
             channel_id=channel or self._channel_id,  # type: ignore[arg-type]
-            thread_ts=thread_ts or self._thread_ts,  # type: ignore[arg-type]
+            thread_ts=thread_ts or self._thread_ts or self._ts,  # type: ignore[arg-type]
             prompts=prompts_arg,
             title=title,
             **kwargs,

slack_bolt/kwargs_injection/async_utils.py

@@ -89,10 +89,13 @@ def build_async_required_kwargs(
     if "agent" in required_arg_names:
         from slack_bolt.agent.async_agent import AsyncBoltAgent
 
+        event = request.body.get("event", {})
+
         all_available_args["agent"] = AsyncBoltAgent(
             client=request.context.client,
             channel_id=request.context.channel_id,
-            thread_ts=request.context.thread_ts,
+            thread_ts=request.context.thread_ts or event.get("thread_ts"),
+            ts=event.get("ts"),
             team_id=request.context.team_id,
             user_id=request.context.user_id,
         )

slack_bolt/kwargs_injection/utils.py

@@ -88,10 +88,13 @@ def build_required_kwargs(
     if "agent" in required_arg_names:
         from slack_bolt.agent.agent import BoltAgent
 
+        event = request.body.get("event", {})
+
         all_available_args["agent"] = BoltAgent(
             client=request.context.client,
             channel_id=request.context.channel_id,
-            thread_ts=request.context.thread_ts,
+            thread_ts=request.context.thread_ts or event.get("thread_ts"),
+            ts=event.get("ts"),
             team_id=request.context.team_id,
             user_id=request.context.user_id,
         )

slack_bolt/request/internals.py

@@ -218,6 +218,9 @@ def extract_thread_ts(payload: Dict[str, Any]) -> Optional[str]:
     # This utility initially supports only the use cases for AI assistants, but it may be fine to add more patterns.
     # That said, note that thread_ts is always required for assistant threads, but it's not for channels.
     # Thus, blindly setting this thread_ts to say utility can break existing apps' behaviors.
+    #
+    # The BoltAgent class handles non-assistant thread_ts separately by reading from the event directly,
+    # allowing it to work correctly without affecting say() behavior.
     if is_assistant_event(payload):
         event = payload["event"]
         if (

tests/slack_bolt/agent/test_agent.py

@@ -92,6 +92,51 @@ def test_chat_stream_passes_extra_kwargs(self):
             buffer_size=512,
         )
 
+    def test_chat_stream_falls_back_to_ts(self):
+        """When thread_ts is not set, chat_stream() falls back to ts."""
+        client = MagicMock(spec=WebClient)
+        client.chat_stream.return_value = MagicMock(spec=ChatStream)
+
+        agent = BoltAgent(
+            client=client,
+            channel_id="C111",
+            team_id="T111",
+            ts="1111111111.111111",
+            user_id="W222",
+        )
+        stream = agent.chat_stream()
+
+        client.chat_stream.assert_called_once_with(
+            channel="C111",
+            thread_ts="1111111111.111111",
+            recipient_team_id="T111",
+            recipient_user_id="W222",
+        )
+        assert stream is not None
+
+    def test_chat_stream_prefers_thread_ts_over_ts(self):
+        """thread_ts takes priority over ts."""
+        client = MagicMock(spec=WebClient)
+        client.chat_stream.return_value = MagicMock(spec=ChatStream)
+
+        agent = BoltAgent(
+            client=client,
+            channel_id="C111",
+            team_id="T111",
+            thread_ts="1234567890.123456",
+            ts="1111111111.111111",
+            user_id="W222",
+        )
+        stream = agent.chat_stream()
+
+        client.chat_stream.assert_called_once_with(
+            channel="C111",
+            thread_ts="1234567890.123456",
+            recipient_team_id="T111",
+            recipient_user_id="W222",
+        )
+        assert stream is not None
+
     def test_set_status_uses_context_defaults(self):
         """BoltAgent.set_status() passes context defaults to WebClient.assistant_threads_setStatus()."""
         client = MagicMock(spec=WebClient)

tests/slack_bolt_async/agent/test_async_agent.py

@@ -118,6 +118,53 @@ async def test_chat_stream_passes_extra_kwargs(self):
             buffer_size=512,
         )
 
+    @pytest.mark.asyncio
+    async def test_chat_stream_falls_back_to_ts(self):
+        """When thread_ts is not set, chat_stream() falls back to ts."""
+        client = MagicMock(spec=AsyncWebClient)
+        client.chat_stream, call_tracker, _ = _make_async_chat_stream_mock()
+
+        agent = AsyncBoltAgent(
+            client=client,
+            channel_id="C111",
+            team_id="T111",
+            ts="1111111111.111111",
+            user_id="W222",
+        )
+        stream = await agent.chat_stream()
+
+        call_tracker.assert_called_once_with(
+            channel="C111",
+            thread_ts="1111111111.111111",
+            recipient_team_id="T111",
+            recipient_user_id="W222",
+        )
+        assert stream is not None
+
+    @pytest.mark.asyncio
+    async def test_chat_stream_prefers_thread_ts_over_ts(self):
+        """thread_ts takes priority over ts."""
+        client = MagicMock(spec=AsyncWebClient)
+        client.chat_stream, call_tracker, _ = _make_async_chat_stream_mock()
+
+        agent = AsyncBoltAgent(
+            client=client,
+            channel_id="C111",
+            team_id="T111",
+            thread_ts="1234567890.123456",
+            ts="1111111111.111111",
+            user_id="W222",
+        )
+        stream = await agent.chat_stream()
+
+        call_tracker.assert_called_once_with(
+            channel="C111",
+            thread_ts="1234567890.123456",
+            recipient_team_id="T111",
+            recipient_user_id="W222",
+        )
+        assert stream is not None
+
     @pytest.mark.asyncio
     async def test_set_status_uses_context_defaults(self):
         """AsyncBoltAgent.set_status() passes context defaults to AsyncWebClient.assistant_threads_setStatus()."""