@llamaindex/ui/src/chat/store/types.ts

A comprehensive UI component library built with React, TypeScript, and Tailwind CSS for LlamaIndex applications

/**
 * Chat Store Types
 * Based on contracts/chat-store.contract.ts
 */

import type { Message, ChatRequestOptions } from "../components/chat.interface";
import type { MessagePart } from "../components/message-parts/types";
import type { StreamingMessage } from "./streaming-message";

/**
 * Chat session state
 *
 * NOTE: sessionId conceptually equals handlerId
 * One chat session = one handler
 * (run_id exists in telemetry but not tracked in state)
 */
export interface ChatSession {
  handlerId: string; // Unique handler identifier (= sessionId)
  workflowName: string;
  indexName?: string;
  messages: Message[];
  status: "idle" | "submitted" | "streaming" | "ready" | "error";
  error: Error | null;
  streamingMessage: StreamingMessage | null; // Event accumulator for current streaming message (contains messageId)
}

/**
 * Options for creating a chat session
 */
export interface CreateSessionOptions {
  workflowName: string;
  handlerId?: string;
  indexName?: string;
  initialMessages?: Message[];
}

/**
 * Chat store state and actions
 */
export interface ChatStoreState {
  // State (key = handlerId, which conceptually = sessionId)
  sessions: Record<string, ChatSession>;

  // Session management
  createSession(options: CreateSessionOptions): Promise<string>; // Returns handlerId
  deleteSession(handlerId: string): void;
  getSession(handlerId: string): ChatSession | undefined;

  // Message operations (public)
  sendMessage(
    handlerId: string,
    message: Message,
    opts?: ChatRequestOptions
  ): Promise<void>;
  setMessages(handlerId: string, messages: Message[]): void;

  // Internal message operations (use underscore prefix)
  _appendMessage(handlerId: string, message: Message): void;
  _updateAssistantMessage(
    handlerId: string,
    messageId: string,
    parts: MessagePart[]
  ): void;

  // Status management
  setStatus(handlerId: string, status: ChatSession["status"]): void;
  setError(handlerId: string, error: Error | null): void;

  // Streaming control
  stop(handlerId: string): Promise<void>;
  regenerate(handlerId: string, messageId?: string): Promise<void>;

  // Internal helpers (use underscore prefix)
  _setStreamingMessage(
    handlerId: string,
    streamingMessage: StreamingMessage | null
  ): void;
}