@laravel/stream-react

Laravel Stream for React

Easily consume streams in your React application.

Installation

npm install @laravel/stream-react

Streaming Responses

[!IMPORTANT] The useStream hook is currently in Beta, the API is subject to change prior to the v1.0.0 release. All notable changes will be documented in the changelog.

The useStream hook allows you to seamlessly consume streamed responses in your React application.

Provide your stream URL and the hook will automatically update data with the concatenated response as data is returned from your server:

import { useStream } from "@laravel/stream-react";

function App() {
    const { data, isFetching, isStreaming, send } = useStream("chat");

    const sendMessage = () => {
        send({
            message: `Current timestamp: ${Date.now()}`,
        });
    };

    return (
        <div>
            <div>{data}</div>
            {isFetching && <div>Connecting...</div>}
            {isStreaming && <div>Generating...</div>}
            <button onClick={sendMessage}>Send Message</button>
        </div>
    );
}

When sending data back to the stream, the active connection to the stream is canceled before sending the new data. All requests are sent as JSON POST requests.

The second argument given to useStream is an options object that you may use to customize the stream consumption behavior:

type StreamOptions = {
    id?: string;
    initialInput?: Record<string, any>;
    headers?: Record<string, string>;
    csrfToken?: string;
    json?: boolean;
    credentials?: RequestCredentials;
    onResponse?: (response: Response) => void;
    onData?: (data: string) => void;
    onCancel?: () => void;
    onFinish?: () => void;
    onError?: (error: Error) => void;
    onBeforeSend?: (request: RequestInit) => boolean | RequestInit | void;
};

onResponse is triggered after a successful initial response from the stream and the raw Response is passed to the callback.

onData is called as each chunk is received, the current chunk is passed to the callback.

onFinish is called when a stream has finished and when an error is thrown during the fetch/read cycle.

onBeforeSend is called right before sending the request to the server and receives the RequestInit object as an argument. Returning false from this callback cancels the request, returning a RequestInit object will override the existing RequestInit object.

By default, a request is not made the to stream on initialization. You may pass an initial payload to the stream by using the initialInput option:

import { useStream } from "@laravel/stream-react";

function App() {
    const { data } = useStream("chat", {
        initialInput: {
            message: "Introduce yourself.",
        },
    });

    return <div>{data}</div>;
}

To cancel a stream manually, you may use the cancel method returned from the hook:

import { useStream } from "@laravel/stream-react";

function App() {
    const { data, cancel } = useStream("chat");

    return (
        <div>
            <div>{data}</div>
            <button onClick={cancel}>Cancel</button>
        </div>
    );
}

Each time the useStream hook is used, a random id is generated to identify the stream. This is sent back to the server with each request in the X-STREAM-ID header.

When consuming the same stream from multiple components, you can read and write to the stream by providing your own id:

// App.tsx
import { useStream } from "@laravel/stream-react";

function App() {
    const { data, id } = useStream("chat");

    return (
        <div>
            <div>{data}</div>
            <StreamStatus id={id} />
        </div>
    );
}

// StreamStatus.tsx
import { useStream } from "@laravel/stream-react";

function StreamStatus({ id }) {
    const { isFetching, isStreaming } = useStream("chat", { id });

    return (
        <div>
            {isFetching && <div>Connecting...</div>}
            {isStreaming && <div>Generating...</div>}
        </div>
    );
}

The useJsonStream hook is identical to the useStream hook except that it will attempt to parse the data as JSON once it has finished streaming:

import { useJsonStream } from "@laravel/stream-react";

type User = {
    id: number;
    name: string;
    email: string;
};

function App() {
    const { data, send } = useJsonStream<{ users: User[] }>("users");

    const loadUsers = () => {
        send({
            query: "taylor",
        });
    };

    return (
        <div>
            <ul>
                {data?.users.map((user) => (
                    <li>
                        {user.id}: {user.name}
                    </li>
                ))}
            </ul>
            <button onClick={loadUsers}>Load Users</button>
        </div>
    );
}

Event Streams (SSE)

The useEventStream hook allows you to seamlessly consume Server-Sent Events (SSE) in your React application.

Provide your stream URL and the hook will automatically update message with the concatenated response as messages are returned from your server:

import { useEventStream } from "@laravel/stream-react";

function App() {
    const { message } = useEventStream("/stream");

    return <div>{message}</div>;
}

You also have access to the array of message parts:

import { useEventStream } from "@laravel/stream-react";

function App() {
    const { messageParts } = useEventStream("/stream");

    return (
        <ul>
            {messageParts.forEach((message) => (
                <li>{message}</li>
            ))}
        </ul>
    );
}

If you'd like to listen to multiple events:

import { useEventStream } from "@laravel/stream-react";

function App() {
    useEventStream("/stream", {
        eventName: ["update", "create"],
        onMessage: (event) => {
            if (event.type === "update") {
                // Handle update
            } else {
                // Handle create
            }
        },
    });

    return null;
}

The second parameter is an options object where all properties are optional (defaults are shown below):

import { useEventStream } from "@laravel/stream-react";

function App() {
    const { message } = useEventStream("/stream", {
        event: "update",
        onMessage: (message) => {
            //
        },
        onError: (error) => {
            //
        },
        onComplete: () => {
            //
        },
        endSignal: "</stream>",
        glue: " ",
        replace: false,
    });

    return <div>{message}</div>;
}

You can close the connection manually by using the returned close function:

import { useEventStream } from "@laravel/stream-react";
import { useEffect } from "react";

function App() {
    const { message, close } = useEventStream("/stream");

    useEffect(() => {
        setTimeout(() => {
            close();
        }, 3000);
    }, []);

    return <div>{message}</div>;
}

The clearMessage function may be used to clear the message content that has been received so far:

import { useEventStream } from "@laravel/stream-react";
import { useEffect } from "react";

function App() {
    const { message, clearMessage } = useEventStream("/stream");

    useEffect(() => {
        setTimeout(() => {
            clearMessage();
        }, 3000);
    }, []);

    return <div>{message}</div>;
}

License

Laravel Stream is open-sourced software licensed under the MIT license.