how to clear the room ?

[wendux]

like io.to("chat").clear() , all socket in room "chat" will leave

[rllalloshi]

@wendux rooms are created and deleted automatically. That means when the room is empty, there are no more clients left on it, it will be deleted.
You can do this to remove all clients from a room:

io.of('/').in('chat').clients((error, socketIds) => {
  if (error) throw error;

  socketIds.forEach(socketId => io.sockets.sockets[socketId].leave('chat'));

});

https://socket.io/docs/server-api/#namespace-clients-callback

[darrachequesne]

To complete @rllalloshi's answer, in a multi-server configuration you should use the removeLeave method of the adapter:

io.of('/').in('chat').clients((error, socketIds) => {
  if (error) throw error;

  socketIds.forEach(socketId => io.of('/').adapter.remoteLeave(socketId, 'chat'));

});

Reference

[mirajehossain]

@wendux rooms are created and deleted automatically. That means when the room is empty, there are no more clients left on it, it will be deleted.
You can do this to remove all clients from a room:

io.of('/').in('chat').clients((error, socketIds) => {
  if (error) throw error;

  socketIds.forEach(socketId => io.sockets.sockets[socketId].leave('chat'));

});

https://socket.io/docs/server-api/#namespace-clients-callback

it did not work in socket.io 2.2.0

[mewsu]

Why is there no simple call to remove all sockets from a room? It is a very common use case

[p3nGu1nZz]

i vote to add. room.kick() function where you can pass in a specific id, an array, or 'ALL" for removing everyone

[Rahulm2310]

@wendux rooms are created and deleted automatically. That means when the room is empty, there are no more clients left on it, it will be deleted.
You can do this to remove all clients from a room:

io.of('/').in('chat').clients((error, socketIds) => {
  if (error) throw error;

  socketIds.forEach(socketId => io.sockets.sockets[socketId].leave('chat'));

});

https://socket.io/docs/server-api/#namespace-clients-callback

@rllalloshi didn't worked me
TypeError: io.of(...).in(...).clients is not a function

[darrachequesne]

For future readers: this was implemented by b25495c and included in [email protected].

Syntax:

// make all Socket instances leave the "room1" room
io.socketsLeave("room1");

// make all Socket instances of the "admin" namespace in the "room1" room leave the "room2" room
io.of("/admin").in("room1").socketsLeave("room2");

Documentation: https://socket.io/docs/v3/migrating-from-3-x-to-4-0/#Additional-utility-methods

[darrachequesne]

@taylordwright44 since the socket joins the room identified by its own ID, you can use:

io.in(theSocketId).socketsLeave("room1");

I've added this example in the documentation. Thanks 👍