window.onload = function() { console.log('window.onload'); var play_log = document.getElementById('play-log'); var last_tag = document.getElementById('last_tag'); function updateLog(data) { last_tag.innerHTML = data.tag; play_log.innerHTML = data.html; } var host = window.document.location.host.replace(/:.*/, ''); var ws = new WebSocket('ws://' + host + ':80'); ws.onmessage = function (event) { console.log(event.data); updateLog(JSON.parse(event.data)); }; };