community: Add model argument for maritalk models and better error handling (#19187)

docs/docs/integrations/chat/maritalk.ipynb

@@ -65,6 +65,7 @@
     "from langchain_core.output_parsers import StrOutputParser\n",
     "\n",
     "llm = ChatMaritalk(\n",
+    "    model=\"sabia-2-medium\",  # Available models: sabia-2-small and sabia-2-medium\n",
     "    api_key=\"\",  # Insert your API key here\n",
     "    temperature=0.7,\n",
     "    max_tokens=100,\n",

libs/community/langchain_community/chat_models/maritalk.py

@@ -1,3 +1,4 @@
+from http import HTTPStatus
 from typing import Any, Dict, List, Optional, Union
 
 import requests
@@ -5,6 +6,32 @@ from langchain_core.callbacks import CallbackManagerForLLMRun
 from langchain_core.language_models.chat_models import SimpleChatModel
 from langchain_core.messages import AIMessage, BaseMessage, HumanMessage, SystemMessage
 from langchain_core.pydantic_v1 import Field
+from requests import Response
+from requests.exceptions import HTTPError
+
+
+class MaritalkHTTPError(HTTPError):
+    def __init__(self, request_obj: Response) -> None:
+        self.request_obj = request_obj
+        try:
+            response_json = request_obj.json()
+            if "detail" in response_json:
+                api_message = response_json["detail"]
+            elif "message" in response_json:
+                api_message = response_json["message"]
+            else:
+                api_message = response_json
+        except Exception:
+            api_message = request_obj.text
+
+        self.message = api_message
+        self.status_code = request_obj.status_code
+
+    def __str__(self) -> str:
+        status_code_meaning = HTTPStatus(self.status_code).phrase
+        formatted_message = f"HTTP Error: {self.status_code} - {status_code_meaning}"
+        formatted_message += f"\nDetail: {self.message}"
+        return formatted_message
 
 
 class ChatMaritalk(SimpleChatModel):
@@ -23,6 +50,14 @@ class ChatMaritalk(SimpleChatModel):
     api_key: str
     """Your MariTalk API key."""
 
+    model: str
+    """Chose one of the available models: 
+    - `sabia-2-medium`
+    - `sabia-2-small`
+    - `sabia-2-medium-2024-03-13`
+    - `sabia-2-small-2024-03-13`
+    - `maritalk-2024-01-08` (deprecated)"""
+
     temperature: float = Field(default=0.7, gt=0.0, lt=1.0)
     """Run inference with this temperature. 
     Must be in the closed interval [0.0, 1.0]."""
@@ -37,10 +72,6 @@ class ChatMaritalk(SimpleChatModel):
     """Nucleus sampling parameter controlling the size of 
     the probability mass considered for sampling."""
 
-    system_message_workaround: bool = Field(default=True)
-    """Whether to include a workaround for system messages 
-    by adding them as a user message."""
-
     @property
     def _llm_type(self) -> str:
         """Identifies the LLM type as 'maritalk'."""
@@ -64,17 +95,13 @@ class ChatMaritalk(SimpleChatModel):
 
         for message in messages:
             if isinstance(message, HumanMessage):
-                parsed_messages.append({"role": "user", "content": message.content})
+                role = "user"
             elif isinstance(message, AIMessage):
-                parsed_messages.append(
-                    {"role": "assistant", "content": message.content}
-                )
-            elif isinstance(message, SystemMessage) and self.system_message_workaround:
-                # Maritalk models do not understand system message.
-                # #Instead we add these messages as user messages.
-                parsed_messages.append({"role": "user", "content": message.content})
-                parsed_messages.append({"role": "assistant", "content": "ok"})
+                role = "assistant"
+            elif isinstance(message, SystemMessage):
+                role = "system"
 
+            parsed_messages.append({"role": role, "content": message.content})
         return parsed_messages
 
     def _call(
@@ -114,6 +141,7 @@ class ChatMaritalk(SimpleChatModel):
 
             data = {
                 "messages": parsed_messages,
+                "model": self.model,
                 "do_sample": self.do_sample,
                 "max_tokens": self.max_tokens,
                 "temperature": self.temperature,
@@ -123,10 +151,11 @@ class ChatMaritalk(SimpleChatModel):
             }
 
             response = requests.post(url, json=data, headers=headers)
-            if response.status_code == 429:
-                return "Rate limited, please try again soon"
-            elif response.ok:
+
+            if response.ok:
                 return response.json().get("answer", "No answer found")
+            else:
+                raise MaritalkHTTPError(response)
 
         except requests.exceptions.RequestException as e:
             return f"An error occurred: {str(e)}"
@@ -144,7 +173,7 @@ class ChatMaritalk(SimpleChatModel):
             A dictionary of the key configuration parameters.
         """
         return {
-            "system_message_workaround": self.system_message_workaround,
+            "model": self.model,
             "temperature": self.temperature,
             "top_p": self.top_p,
             "max_tokens": self.max_tokens,