A main.rs for tide-websocket use.Unfortunately it closes the WebSocket immediately

app.js

// This is at present within a script tag in html page
app = function(){

  
  function onLoad()
  {
    console.log("[page] loaded");
    this.websocket = new WebSocket(this.wsUri);
    this.websocket.onopen = this.onWsOpen;
    this.websocket.onclose = this.onWsClose;
    this.websocket.onmessage = this.onWsMessage;
    this.websocket.onerror = this.onWsError;      
  }

  function onWsOpen(ev)
  {
    console.log(`[ws open] ${this.websocket}`);
    this.websocket.send("Testing 123");
  }

  function onWsClose(ev)
  {
    if (ev.wasClean) {
      console.log(`[ws close] Connection closed cleanly, code=${ev.code} reason=${ev.reason}`);
    } else {
      console.log(`[ws close] Connection died, ev=${ev}`);
    }
  }

  function onWsMessage(ev)
  {
    console.log(`[ws rcv] ${ev.data}`);

  }

  function onWsError(ev)
  {
    console.log(`[ws err] ${ev}`);
  }

  function allowDrop(ev)
  {
    ev.preventDefault();
  }

  function drag(ev)
  {
    var srcId=ev.target.id;
    console.log("drag=>target:"+srcId);
    ev.dataTransfer.setData("text", srcId);
  }

  function drop(ev)
  {
    ev.preventDefault();
    var srcId=ev.dataTransfer.getData("text");
    var text = document.getElementById(srcId).textContent;
    console.log("drop=>srcId:"+srcId+" text:"+text);
	  event.target.textContent = text;
    document.getElementById("choice").value = text;
    this.chosen = document.getElementById("choice").value;
  }

  function is_locked()
  {
    return (locked == true)
  }

  function lock()
  {
    console.log("Now locked at "+this.chosen);
    locked = true
  }

  function card()
  {
    return this.chosen;
  }

  return {
    onLoad: onLoad,
    allowDrop: allowDrop,
    drag: drag,
    drop: drop,
    lock: lock,
    card: card,
    onWsOpen: onWsOpen,
    onWsClose: onWsClose,
    onWsMessage: onWsMessage,
    onWsError: onWsError,
    chosen: "?",
    locked: false,
    wsUri: "ws://127.0.0.1:8080/ws",
    websocket: undefined
  }
}();

main.rs

use serde_json::{Map, Value};
use tide_websockets::{
    WebSocket
};
use async_std::stream::StreamExt;

const _DEFAULT_4XX_BODY: &[u8] = b"Oops! I can't find what you're looking for..." as &[_];
const _DEFAULT_5XX_BODY: &[u8] = b"I'm broken, apparently." as &[_];

fn start_msg() -> Map<String, Value> {
    let mut map = Map::new();
    map.insert("Bool Example".to_string(), false.into());
    map.insert("String Example".to_string(), "Str".to_string().into());    
    map.insert("Number Example".to_string(), 2.into());
    map
}

#[async_std::main]
async fn main() -> std::result::Result<(), std::io::Error> {
    tide::log::start();
    let mut app = tide::new();
    app.at("/").serve_file("plan.html")?;
    app.at("/ws").get(WebSocket::new(
        |_req, mut stream| async move {
            stream.send_json(&start_msg()).await.unwrap();
            loop {
                let msg = stream.next().await.unwrap();
                tide::log::info!("Received msg-> {:?}\n", msg);
            }
        }));
    app.listen("127.0.0.1:8080").await?;
    Ok(())
}