This commit adds the following methods:
- fetchSockets: returns the matching socket instances
Syntax:
```js
// return all Socket instances
const sockets = await io.fetchSockets();
// return all Socket instances of the "admin" namespace in the "room1" room
const sockets = await io.of("/admin").in("room1").fetchSockets();
```
- socketsJoin: makes the matching socket instances join the specified rooms
Syntax:
```js
// make all Socket instances join the "room1" room
io.socketsJoin("room1");
// make all Socket instances of the "admin" namespace in the "room1" room join the "room2" room
io.of("/admin").in("room1").socketsJoin("room2");
```
- socketsLeave: makes the matching socket instances leave the specified rooms
Syntax:
```js
// 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");
```
- disconnectSockets: makes the matching socket instances disconnect
Syntax:
```js
// make all Socket instances disconnect
io.disconnectSockets();
// make all Socket instances of the "admin" namespace in the "room1" room disconnect
io.of("/admin").in("room1").disconnectSockets();
```
Those methods share the same semantics as broadcasting. They will also
work with multiple Socket.IO servers when using the Redis adapter. In
that case, the fetchSockets() method will return a list of RemoteSocket
instances, which expose a subset of the methods and attributes of the
Socket class (the "request" attribute cannot be mocked, for example).
Related:
- https://github.com/socketio/socket.io/issues/3042
- https://github.com/socketio/socket.io/issues/3418
- https://github.com/socketio/socket.io/issues/3570
- https://github.com/socketio/socket.io-redis/issues/283