Module haystack_experimental.components.retrievers.chat_message_retriever

ChatMessageRetriever

Retrieves chat messages from the underlying ChatMessageStore.

Usage example:

from haystack.dataclasses import ChatMessage
from haystack_experimental.components.retrievers import ChatMessageRetriever
from haystack_experimental.chat_message_stores.in_memory import InMemoryChatMessageStore

messages = [
    ChatMessage.from_assistant("Hello, how can I help you?"),
    ChatMessage.from_user("Hi, I have a question about Python. What is a Protocol?"),
]

message_store = InMemoryChatMessageStore()
message_store.write_messages(messages)
retriever = ChatMessageRetriever(message_store)

result = retriever.run()

print(result["messages"])

ChatMessageRetriever.__init__

def __init__(message_store: ChatMessageStore, last_k: int = 10)

Create the ChatMessageRetriever component.

Arguments:

• message_store: An instance of a ChatMessageStore.
• last_k: The number of last messages to retrieve. Defaults to 10 messages if not specified.

ChatMessageRetriever.to_dict

def to_dict() -> Dict[str, Any]

Serializes the component to a dictionary.

Returns:

Dictionary with serialized data.

ChatMessageRetriever.from_dict

@classmethod
def from_dict(cls, data: Dict[str, Any]) -> "ChatMessageRetriever"

Deserializes the component from a dictionary.

Arguments:

• data: The dictionary to deserialize from.

Returns:

The deserialized component.

ChatMessageRetriever.run

@component.output_types(messages=List[ChatMessage])
def run(last_k: Optional[int] = None)

Run the ChatMessageRetriever

Arguments:

• last_k: The number of last messages to retrieve. This parameter takes precedence over the last_k parameter passed to the ChatMessageRetriever constructor. If unspecified, the last_k parameter passed to the constructor will be used.

Raises:

• ValueError: If last_k is not None and is less than 1

Returns:

• messages - The retrieved chat messages.