"""Callback handler for Context AI"""
import os
from typing import Any, Dict, List
from uuid import UUID
from langchain_core.callbacks import BaseCallbackHandler
from langchain_core.messages import BaseMessage
from langchain_core.outputs import LLMResult
from langchain_core.utils import guard_import
[docs]
def import_context() -> Any:
"""Import the `getcontext` package."""
return (
guard_import("getcontext", pip_name="python-context"),
guard_import("getcontext.token", pip_name="python-context").Credential,
guard_import(
"getcontext.generated.models", pip_name="python-context"
).Conversation,
guard_import("getcontext.generated.models", pip_name="python-context").Message,
guard_import(
"getcontext.generated.models", pip_name="python-context"
).MessageRole,
guard_import("getcontext.generated.models", pip_name="python-context").Rating,
)
[docs]
class ContextCallbackHandler(BaseCallbackHandler):
"""Callback Handler that records transcripts to the Context service.
(https://context.ai).
Keyword Args:
token (optional): The token with which to authenticate requests to Context.
Visit https://with.context.ai/settings to generate a token.
If not provided, the value of the `CONTEXT_TOKEN` environment
variable will be used.
Raises:
ImportError: if the `context-python` package is not installed.
Chat Example:
>>> from langchain_community.llms import ChatOpenAI
>>> from langchain_community.callbacks import ContextCallbackHandler
>>> context_callback = ContextCallbackHandler(
... token="<CONTEXT_TOKEN_HERE>",
... )
>>> chat = ChatOpenAI(
... temperature=0,
... headers={"user_id": "123"},
... callbacks=[context_callback],
... openai_api_key="API_KEY_HERE",
... )
>>> messages = [
... SystemMessage(content="You translate English to French."),
... HumanMessage(content="I love programming with LangChain."),
... ]
>>> chat.invoke(messages)
Chain Example:
>>> from langchain.chains import LLMChain
>>> from langchain_community.chat_models import ChatOpenAI
>>> from langchain_community.callbacks import ContextCallbackHandler
>>> context_callback = ContextCallbackHandler(
... token="<CONTEXT_TOKEN_HERE>",
... )
>>> human_message_prompt = HumanMessagePromptTemplate(
... prompt=PromptTemplate(
... template="What is a good name for a company that makes {product}?",
... input_variables=["product"],
... ),
... )
>>> chat_prompt_template = ChatPromptTemplate.from_messages(
... [human_message_prompt]
... )
>>> callback = ContextCallbackHandler(token)
>>> # Note: the same callback object must be shared between the
... LLM and the chain.
>>> chat = ChatOpenAI(temperature=0.9, callbacks=[callback])
>>> chain = LLMChain(
... llm=chat,
... prompt=chat_prompt_template,
... callbacks=[callback]
... )
>>> chain.run("colorful socks")
"""
[docs]
def __init__(self, token: str = "", verbose: bool = False, **kwargs: Any) -> None:
(
self.context,
self.credential,
self.conversation_model,
self.message_model,
self.message_role_model,
self.rating_model,
) = import_context()
token = token or os.environ.get("CONTEXT_TOKEN") or ""
self.client = self.context.ContextAPI(credential=self.credential(token))
self.chain_run_id = None
self.llm_model = None
self.messages: List[Any] = []
self.metadata: Dict[str, str] = {}
[docs]
def on_chat_model_start(
self,
serialized: Dict[str, Any],
messages: List[List[BaseMessage]],
*,
run_id: UUID,
**kwargs: Any,
) -> Any:
"""Run when the chat model is started."""
llm_model = kwargs.get("invocation_params", {}).get("model", None)
if llm_model is not None:
self.metadata["model"] = llm_model
if len(messages) == 0:
return
for message in messages[0]:
role = self.message_role_model.SYSTEM
if message.type == "human":
role = self.message_role_model.USER
elif message.type == "system":
role = self.message_role_model.SYSTEM
elif message.type == "ai":
role = self.message_role_model.ASSISTANT
self.messages.append(
self.message_model(
message=message.content,
role=role,
)
)
[docs]
def on_llm_end(self, response: LLMResult, **kwargs: Any) -> None:
"""Run when LLM ends."""
if len(response.generations) == 0 or len(response.generations[0]) == 0:
return
if not self.chain_run_id:
generation = response.generations[0][0]
self.messages.append(
self.message_model(
message=generation.text,
role=self.message_role_model.ASSISTANT,
)
)
self._log_conversation()
[docs]
def on_chain_start(
self, serialized: Dict[str, Any], inputs: Dict[str, Any], **kwargs: Any
) -> None:
"""Run when chain starts."""
self.chain_run_id = kwargs.get("run_id", None)
[docs]
def on_chain_end(self, outputs: Dict[str, Any], **kwargs: Any) -> None:
"""Run when chain ends."""
self.messages.append(
self.message_model(
message=outputs["text"],
role=self.message_role_model.ASSISTANT,
)
)
self._log_conversation()
self.chain_run_id = None
def _log_conversation(self) -> None:
"""Log the conversation to the context API."""
if len(self.messages) == 0:
return
self.client.log.conversation_upsert(
body={
"conversation": self.conversation_model(
messages=self.messages,
metadata=self.metadata,
)
}
)
self.messages = []
self.metadata = {}
