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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<style type="text/css">
input[type="text"] { width: 300px; }
.muted {color: #CCCCCC; font-size: 10px;}
</style>
<script src="https://unpkg.com/text-encoding@0.6.4/lib/encoding-indexes.js"></script>
<script src="https://unpkg.com/text-encoding@0.6.4/lib/encoding.js"></script>
<script type="text/javascript" src="https://cdn.jsdelivr.net/gh/centrifugal/centrifuge-js@master/dist/centrifuge.protobuf.min.js"></script>
<script type="text/javascript">
// helper functions to work with escaping html.
const tagsToReplace = {'&': '&', '<': '<', '>': '>'};
function replaceTag(tag) {return tagsToReplace[tag] || tag;}
function safeTagsReplace(str) {return str.replace(/[&<>]/g, replaceTag);}
const channel = "chat:index";
window.addEventListener('load', function() {
const input = document.getElementById("input");
const container = document.getElementById('messages');
const centrifuge = new Centrifuge('ws://localhost:8000/connection/websocket?format=protobuf');
// bind listeners on centrifuge object instance events.
centrifuge.on('connect', function(ctx){
drawText('Connected with client ID ' + ctx.client + ' over ' + ctx.transport);
input.removeAttribute('disabled');
});
centrifuge.on('publish', function(ctx) {
let str = new TextDecoder("utf-8").decode(ctx.data);
drawText('Server-side publication from channel ' + ctx.channel + ": " + str);
});
centrifuge.on('join', function(ctx) {
drawText('Server-side join from channel ' + ctx.channel + ": " + JSON.stringify(ctx.info));
});
centrifuge.on('leave', function(ctx) {
drawText('Server-side leave from channel ' + ctx.channel + ": " + JSON.stringify(ctx.info));
});
centrifuge.on('subscribe', function(ctx) {
drawText('Subscribe to server-side channel ' + ctx.channel + ' (resubscribed: ' + ctx.isResubscribe + ', recovered: ' + ctx.recovered + ')');
});
centrifuge.on('unsubscribe', function(ctx) {
drawText('Unsubscribe from server-side channel ' + ctx.channel);
});
centrifuge.on('message', function(data) {
const str = new TextDecoder("utf-8").decode(data);
drawText(str);
// Echo data back to server with 'ack' prefix.
const echoData = new TextEncoder("utf-8").encode("ack " + str);
centrifuge.send(echoData);
});
centrifuge.on('disconnect', function(ctx){
drawText('Disconnected: ' + ctx.reason + (ctx.reconnect?", will try to reconnect":", won't try to reconnect"));
input.removeAttribute('disabled');
});
// subscribe on channel and bind various event listeners. Actual
// subscription request will be sent after client connects to
// a server.
const sub = centrifuge.subscribe(channel, handleMessage)
.on("join", handleJoin)
.on("leave", handleLeave)
.on("unsubscribe", handleUnsubscribe)
.on("subscribe", handleSubscribe)
.on("error", handleSubscribeError);
// Trigger actual connection establishing with a server.
// At this moment actual client work starts - i.e. subscriptions
// defined start subscribing etc.
centrifuge.connect();
function handleSubscribe(ctx) {
drawText('Subscribed on channel ' + ctx.channel);
const rpcRequest = {"method": "getCurrentYear"}
const binary = new TextEncoder("utf-8").encode(JSON.stringify(rpcRequest));
centrifuge.rpc(binary).then(function(result){
const str = new TextDecoder("utf-8").decode(result.data);
drawText("RPC response data: " + str);
}, function(err) {
drawText("RPC error: " + JSON.stringify(err));
});
}
function handleSubscribeError(err) {
drawText('Error subscribing on channel ' + err.channel + ': ' + err.message);
}
function handleMessage(message) {
const str = new TextDecoder("utf-8").decode(message.data);
const data = JSON.parse(str);
let clientID;
if (message.info){
clientID = message.info.client;
} else {
clientID = null;
}
const inputText = data["input"].toString();
const text = safeTagsReplace(inputText) + ' <span class="muted">from ' + clientID + '</span>';
drawText(text);
}
function handleJoin(message) {
drawText('Someone joined channel ' + this.channel + ' (uid ' + message.info["client"] + ', user '+ message.info["user"] +')');
}
function handleLeave(message) {
drawText('Someone left channel ' + this.channel + ' (uid ' + message.info["client"] + ', user '+ message.info["user"] +')');
}
function handleUnsubscribe(sub) {
drawText('Unsubscribed from channel ' + sub.channel);
}
function drawText(text) {
let e = document.createElement('li');
e.innerHTML = [(new Date()).toString(), ' ' + text].join(':');
container.insertBefore(e, container.firstChild);
}
document.getElementById('form').addEventListener('submit', function(event) {
event.preventDefault();
const data = {"input": input.value};
const binaryData = new TextEncoder("utf-8").encode(JSON.stringify(data));
sub.publish(binaryData).then(function() {
console.log('message accepted by server');
}, function(err) {
drawText("Publish error: " + err.code + ' ' + err.message);
console.log('error publishing message', err);
});
input.value = '';
});
});
</script>
</head>
<body>
<form id="form">
<input type="text" id="input" autocomplete="off" />
<input type="submit" id="submit" value="ยป">
</form>
<ul id="messages"></ul>
</body>
</html>
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