@johnhenry/aimatey-react-stream

Note: Previously published as [email protected].

React components and utilities for streaming AI responses.

Part of the aimatey monorepo.

Installation

npm install @johnhenry/aimatey-react-stream

Quick Start

import { StreamProvider, useStreamContext, StreamText } from '@johnhenry/aimatey-react-stream';

// Wrap your app with StreamProvider
function App() {
  return (
    <StreamProvider maxStreams={10}>
      <ChatComponent />
    </StreamProvider>
  );
}

// Use streaming in components
function ChatComponent() {
  const { startStream, appendToStream, completeStream, getStream } = useStreamContext();
  const [streamId, setStreamId] = useState<string | null>(null);

  const handleSend = async () => {
    const id = `msg-${Date.now()}`;
    setStreamId(id);
    startStream(id);

    const response = await fetch('/api/chat', { method: 'POST' });
    const reader = response.body?.getReader();
    const decoder = new TextDecoder();

    while (reader) {
      const { done, value } = await reader.read();
      if (done) break;
      appendToStream(id, decoder.decode(value));
    }

    completeStream(id);
  };

  const stream = streamId ? getStream(streamId) : null;

  return (
    <div>
      {stream && (
        <StreamText
          text={stream.text}
          isStreaming={stream.isStreaming}
          showCursor={true}
        />
      )}
      <button onClick={handleSend}>Send</button>
    </div>
  );
}

Exports

Components

• StreamProvider - Context provider for stream state management
• StreamText - Display streaming text with cursor
• TypeWriter - Typewriter effect for static text

Hooks

• useStreamContext - Access stream management functions
• useStreamState - Get state for a specific stream

Utilities

• createTextStream - Create controlled text stream from fetch response
• parseSSEStream - Parse Server-Sent Events
• transformStream - Transform stream data
• mergeStreams - Merge multiple streams
• fromAsyncIterable - Convert async iterable to stream
• toAsyncIterable - Convert stream to async iterable

Types

• StreamState, StreamContextValue, StreamProviderProps
• StreamTextProps, TypeWriterProps
• CreateTextStreamOptions, SSEEvent

API Reference

StreamProvider

Context provider for managing multiple concurrent streams.

<StreamProvider maxStreams={100}>
  {children}
</StreamProvider>

Props:

• maxStreams - Maximum streams to keep (default: 100, oldest completed removed when exceeded)

useStreamContext

Access stream management functions.

const {
  streams,          // Map<string, StreamState> - All streams
  getStream,        // (id: string) => StreamState | undefined
  startStream,      // (id: string, metadata?: object) => void
  updateStream,     // (id: string, text: string) => void - Replace text
  appendToStream,   // (id: string, chunk: string) => void - Append text
  completeStream,   // (id: string) => void - Mark complete
  setStreamError,   // (id: string, error: Error) => void
  removeStream,     // (id: string) => void
  clearAllStreams,  // () => void
} = useStreamContext();

useStreamState

Get state for a specific stream by ID.

const stream = useStreamState('message-1');
// stream: { id, text, isStreaming, error, metadata } | undefined

StreamText

Display streaming text with optional blinking cursor.

<StreamText
  text="Hello world"
  isStreaming={true}
  showCursor={true}           // Show cursor while streaming
  cursor="▋"                  // Cursor character
  cursorBlinkInterval={500}   // Blink speed in ms
  className="my-class"
  renderText={(text) => <Markdown>{text}</Markdown>}
/>

TypeWriter

Simulate typing effect for non-streaming text.

<TypeWriter
  text="Welcome to Aimatey!"
  speed={30}                  // ms per character
  delay={500}                 // ms before starting
  showCursor={true}
  cursor="▋"
  onComplete={() => console.log('Done!')}
/>

Stream Utilities

import {
  createTextStream,
  parseSSEStream,
  fromAsyncIterable,
} from '@johnhenry/aimatey-react-stream';

// Create text stream from fetch response
const text = await createTextStream(response, {
  onChunk: (chunk) => console.log(chunk),
  onComplete: (fullText) => console.log('Done:', fullText),
  signal: abortController.signal,
});

// Parse SSE events
for await (const event of parseSSEStream(response)) {
  console.log(event.data); // { type: 'data' | 'event', data: string }
}

License

MIT - see LICENSE for details.