React hooks for socket.io 4.x
Examples:
Usage:
- Wrap your components with the provider
import { IoProvider } from 'socket.io-react-hook'; <IoProvider> <App /> </IoProvider>
import { useSocket, useSocketEvent } from 'socket.io-react-hook'; const { socket, error } = useSocket(); const { lastMessage, sendMessage } = useSocketEvent(socket, 'message'); OR const { lastMessage, sendMessage } = useSocketEvent('message');
If the socket parameter is not passed to useSocketEvent, the options of useSocket can be passed in the second parameter of useSocketEvent. For example
const { lastMessage, sendMessage } = useSocketEvent('message', { path: "/socket", extraHeaders: ... });
useSocket and useSocketEvent forwards all relevant parameters to socket.io constructor.
See the available options here
If the socket connection depends on state, use it like this:
The connection will be initiated once the socket is enabled.
The connection for a namespace is shared between your components, feel free to use the hooks in multiple components.
import { useCookie } from 'react-use'; import { useSocket } from 'socket.io-react-hook'; export const useAuthenticatedSocket = (namespace?: string) => { const [accessToken] = useCookie('jwt'); return useSocket(namespace, { enabled: !!accessToken, }); };
The useSocket hook always returns a socket-like object, even before a succesful connection. You don't have to check whether it is undefined.
Example:
export const useAuthenticatedSocket = (namespace?: string) => { const [accessToken] = useCookie('jwt'); return useSocket(namespace, { enabled: !!accessToken, }); }; const Index = () => { const { socket, connected, error } = useAuthenticatedSocket(); const { lastMessage, sendMessage } = useSocketEvent<string>(socket, 'eventName'); return <div>{ lastMessage }</div> }
const Index = () => { const [messages, setMessages] = useState([]); const { socket, connected, error } = useAuthenticatedSocket(); const onMessage = (message) => setMessages((state) => [...state, message]); useSocketEvent<string>(socket, "eventName", { onMessage }); ... };
useSocketEvent parameters:
- socket: SocketIo object
- event: string
- options:
- onMessage: (message) => void
- keepPrevious: (default false) if true, useSocketEvent will immediately return the last available value of lastMessage after being remounted
Emitting messages works as always:
const { socket, connected, error } = useSocket(); socket.emit('eventName', data);
Or by calling sendMessage
//Client const { socket, lastMessage, sendMessage } = useSocketEvent<string>(socket, 'eventName'); ... const response = await sendMessage<{ status: string }>("hi server"); console.log(response.status) // "ok" //Server io.on("connection", (socket) => { socket.on("eventName", (message, callback) => { console.log(message) // "hi server" callback({ status: "ok" }); }); });
interface ServerToClientEvents { noArg: () => void; basicEmit: (a: number, b: string, c: any) => void; withAck: (d: string, callback: (e: number) => void) => void; } interface ClientToServerEvents { hello: () => void; } const { socket } = useSocket<ServerToClientEvents, ClientToServerEvents>(); socket.on("withAck", (d, callback) => {}); socket.emit("hello");