我是 wqtt 服务器的新手。我正在尝试使用mqtt.js他们网站上提供的示例连接到 mosquitto 测试服务器。
但我无法连接到服务器。我总是收到以下错误：
WebSocket connection to 'ws://test.mosquitto.org/:8080/mqtt' failed: Error in connection establishment: net::ERR_NAME_NOT_RESOLVED.
请帮忙。下面是我的html：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js" type="text/javascript"></script>
<script src="http://www.hivemq.com/demos/websocket-client/js/mqttws31.js" type="text/javascript"></script>
<title>HiveMQ MQTT Websocket Demo App</title>
<script type="text/javascript">
var client = new Messaging.Client("test.mosquitto.org", 8080, "myclientid_" + parseInt(Math.random() * 100, 10));
//Gets called if the websocket/mqtt connection gets disconnected for any reason
client.onConnectionLost = function (responseObject) {
//Depending on your scenario you could implement a reconnect logic here
alert("connection lost: " + responseObject.errorMessage);
};
//Gets called whenever you receive a message for your subscriptions
client.onMessageArrived = function (message) {
//Do something with the push message you received
$('#messages').append('Topic: ' + message.destinationName + ' | ' + message.payloadString + '');
};
//Connect Options
var options = {
timeout: 3,
//Gets Called if the connection has sucessfully been established
onSuccess: function () {
alert("Connected");
},
//Gets Called if the connection could not be established
onFailure: function (message) {
document.write("Connection failed: " + message.errorMessage);
alert("Connection failed: " + message.errorMessage);
}
};
//Creates a new Messaging.Message Object and sends it to the HiveMQ MQTT Broker
var publish = function (payload, topic, qos) {
//Send your message (also possible to serialize it as JSON or protobuf or just use a string, no limitations)
var message = new Messaging.Message(payload);
message.destinationName = topic;
message.qos = qos;
client.send(message);
}
</script>
</head>
<body>
<button onclick="client.connect(options);">1. Connect</button>
<button onclick="client.subscribe('testtopic/#', {qos: 2}); alert('Subscribed');">2. Subscribe</button>
<button onclick="publish('Hello Foo !','testtopic/bar',2);">3. Publish</button>
<button onclick="client.disconnect();">(4. Disconnect)</button>
<div id="messages"></div>
</body>