Handle LLMs lacking concurrency support in Chat UI (#506)

* specify no concurrency in GPT4All models

* handle LLMs lacking concurrency support in chat

* add annotation & default for uses_llm attr

* edit reply msg

packages/jupyter-ai-magics/jupyter_ai_magics/providers.py

@@ -362,6 +362,11 @@ def __init__(self, **kwargs):
     async def _acall(self, *args, **kwargs) -> Coroutine[Any, Any, str]:
         return await self._call_in_executor(*args, **kwargs)
 
+    @property
+    def allows_concurrency(self):
+        # At present, GPT4All providers fail with concurrent messages. See #481.
+        return False
+
 
 HUGGINGFACE_HUB_VALID_TASKS = (
     "text2text-generation",

packages/jupyter-ai/jupyter_ai/chat_handlers/ask.py

@@ -31,6 +31,8 @@ class AskChatHandler(BaseChatHandler):
     help = "Ask a question about your learned data"
     routing_type = SlashCommandRoutingType(slash_id="ask")
 
+    uses_llm = True
+
     def __init__(self, retriever, *args, **kwargs):
         super().__init__(*args, **kwargs)
 

packages/jupyter-ai/jupyter_ai/chat_handlers/base.py

@@ -58,6 +58,15 @@ class BaseChatHandler:
 
     routing_type: HandlerRoutingType = ...
 
+    uses_llm: ClassVar[bool] = True
+    """Class attribute specifying whether this chat handler uses the LLM
+    specified by the config. Subclasses should define this. Should be set to
+    `False` for handlers like `/help`."""
+
+    _requests_count = 0
+    """Class attribute set to the number of requests that Jupyternaut is
+    currently handling."""
+
     def __init__(
         self,
         log: Logger,
@@ -82,11 +91,26 @@ def __init__(
 
     async def on_message(self, message: HumanChatMessage):
         """
-        Method which receives a human message and processes it via
-        `self.process_message()`, calling `self.handle_exc()` when an exception
-        is raised. This method is called by RootChatHandler when it routes a
-        human message to this chat handler.
+        Method which receives a human message, calls `self.get_llm_chain()`, and
+        processes the message via `self.process_message()`, calling
+        `self.handle_exc()` when an exception is raised. This method is called
+        by RootChatHandler when it routes a human message to this chat handler.
         """
+
+        # check whether the configured LLM can support a request at this time.
+        if self.uses_llm and BaseChatHandler._requests_count > 0:
+            lm_provider_klass = self.config_manager.lm_provider
+            lm_provider_params = self.config_manager.lm_provider_params
+            lm_provider = lm_provider_klass(**lm_provider_params)
+
+            if not lm_provider.allows_concurrency:
+                self.reply(
+                    "The currently selected language model can process only one request at a time. Please wait for me to reply before sending another question.",
+                    message,
+                )
+                return
+
+        BaseChatHandler._requests_count += 1
         try:
             await self.process_message(message)
         except Exception as e:
@@ -96,6 +120,8 @@ async def on_message(self, message: HumanChatMessage):
                 await self.handle_exc(e, message)
             except Exception as e:
                 await self._default_handle_exc(e, message)
+        finally:
+            BaseChatHandler._requests_count -= 1
 
     async def process_message(self, message: HumanChatMessage):
         """

packages/jupyter-ai/jupyter_ai/chat_handlers/clear.py

@@ -11,6 +11,8 @@ class ClearChatHandler(BaseChatHandler):
     help = "Clear the chat window"
     routing_type = SlashCommandRoutingType(slash_id="clear")
 
+    uses_llm = False
+
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
 

packages/jupyter-ai/jupyter_ai/chat_handlers/default.py

@@ -37,6 +37,8 @@ class DefaultChatHandler(BaseChatHandler):
     help = "Responds to prompts that are not otherwise handled by a chat handler"
     routing_type = SlashCommandRoutingType(slash_id=None)
 
+    uses_llm = True
+
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         self.memory = ConversationBufferWindowMemory(return_messages=True, k=2)

packages/jupyter-ai/jupyter_ai/chat_handlers/generate.py

@@ -221,6 +221,8 @@ class GenerateChatHandler(BaseChatHandler):
     help = "Generate a Jupyter notebook from a text prompt"
     routing_type = SlashCommandRoutingType(slash_id="generate")
 
+    uses_llm = True
+
     def __init__(self, preferred_dir: str, log_dir: Optional[str], *args, **kwargs):
         super().__init__(*args, **kwargs)
         self.log_dir = Path(log_dir) if log_dir else None

packages/jupyter-ai/jupyter_ai/chat_handlers/help.py

@@ -41,6 +41,8 @@ class HelpChatHandler(BaseChatHandler):
     help = "Display this help message"
     routing_type = SlashCommandRoutingType(slash_id="help")
 
+    uses_llm = False
+
     def __init__(self, *args, chat_handlers: Dict[str, BaseChatHandler], **kwargs):
         super().__init__(*args, **kwargs)
         self._chat_handlers = chat_handlers

packages/jupyter-ai/jupyter_ai/chat_handlers/learn.py

@@ -36,6 +36,8 @@ class LearnChatHandler(BaseChatHandler):
     help = "Teach Jupyternaut about files on your system"
     routing_type = SlashCommandRoutingType(slash_id="learn")
 
+    uses_llm = True
+
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         self.parser.prog = "/learn"