Realtime State Application

GState watch API could use for realtime application. It is simple chat sample which use state.watch and socket.io.

var state = new GState();
var counter = Date.now();
io.on("connection", function(socket) {
   console.log("client connect");
   const watcher = state.watch({
     messages: { _: 1 } 
   },
   result => {
    console.log(result);
    if (result && Array.isArray(result.messages)) {  

       socket.emit("messages", result.messages.slice(-10));
    }
   });
    socket.on("disconnect", function() {
      console.log("client disconnect");
      watcher();
    });
   socket.on("new message", function(msg) {
    counter++;
    const id = new Date().getTime() + counter % 1e9;
    state.set({
      messages: {
        [id]: msg
      }});
  });
});