langchain.js
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    Class PlanetScaleChatMessageHistory

    Class for storing and retrieving chat message history from a PlanetScale database. Extends the BaseListChatMessageHistory class.

    const chatHistory = new PlanetScaleChatMessageHistory({
      tableName: "stored_message",
      sessionId: "lc-example",
      config: {
        url: "ADD_YOURS_HERE",
      },
    });
    const chain = new ConversationChain({
      llm: new ChatOpenAI({ model: "gpt-4o-mini" }),
      memory: chatHistory,
    });
    const response = await chain.invoke({
      input: "What did I just say my name was?",
    });
    console.log({ response });

    Hierarchy (View Summary)

    Index

    Constructors

    constructor

    Properties

    client lc_namespace

    Accessors

    lc_secrets

    Methods

    addMessage clear getMessages

    Constructors

    Properties

    client: Client
    lc_namespace: string[] = ...

    Accessors

    • get lc_secrets(): {
          "config.host": string;
          "config.password": string;
          "config.url": string;
          "config.username": string;
      }

      Returns {
          "config.host": string;
          "config.password": string;
          "config.url": string;
          "config.username": string;
      }

    Methods

    • Method to add a new message to the PlanetScale database for the current session.

      Parameters

      • message: BaseMessage

        The BaseMessage object to be added to the database.

      Returns Promise<void>

      Promise that resolves to void.

    • Method to delete all messages from the PlanetScale database for the current session.

      Returns Promise<void>

      Promise that resolves to void.

    • Method to retrieve all messages from the PlanetScale database for the current session.

      Returns Promise<BaseMessage[]>

      Promise that resolves to an array of BaseMessage objects.

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