我有一个nodejs(node v0.10.26)mqtt代码,它将字符串发布到远程mqtt服务器上的主题。现在我正试图将字节数组和缓冲区发布到同一主题,但是我得到一个错误
代码:
var ProtoBuf = require("protobufjs");
var mqtt = require('mqtt');
var builder = ProtoBuf.loadProtoFile('event.proto'),
as2 = builder.build('as2'),
Message=as2.Message;
var message = new Message({
"message_type": "EMOTICON"
});
console.log("message : "+message);
var buffer_message= message.encode();
client = mqtt.createClient(1883,'hostNameOfMQTT',{ encoding: 'binary' });
client.publish('NewTopic',buffer_message);
client.on('connect', function() {
console.log("Message published : "+buffer_message);
client.end();
});
当我执行的时候我得到了这个错误
node.exe samplemqtt.js文件
C:\节点>节点.exe simplemqtt.js
消息:.as2.message
C:\节点\节点\模块\mqtt\lib\generate.js:178
length+=缓冲区,bytelength(有效载荷);
^
TypeError: Argument must be a string
at Object.module.exports.publish (C:\node\node_modules\mqtt\lib\
generate.js:178:22)
at Connection.eval [as publish] (eval at <anonymous> (C:\node\no
de_modules\mqtt\lib\connection.js:58:29), <anonymous>:2:26)
at MqttClient._sendPacket (C:\node\node_modules\mqtt\lib\client.
js:430:20)
at MqttClient.<anonymous> (C:\node\node_modules\mqtt\lib\client.
js:105:12)
at MqttClient.EventEmitter.emit (events.js:117:20)
at MqttClient._handleConnack (C:\node\node_modules\mqtt\lib\clie
nt.js:498:10)
at Connection.<anonymous> (C:\node\node_modules\mqtt\lib\client.
js:191:10)
at Connection.EventEmitter.emit (events.js:95:17)
at Connection._write (C:\node\node_modules\mqtt\lib\connection.j
s:187:12)
at doWrite (_stream_writable.js:226:10)
但是,当我尝试发布buffer_message.to string()时,我得到的对象详细信息是一个字符串,而不是实际的arraybuffer?是吗?
client.publish('ankittopic',buffer_message.tostring());
使用tostring()->bytebuffer输出(offer=0,markedoffset=-1,length=2,capacity=16)
我不想使用to字符串,我希望实际的bytebuffer通过mqtt传输。
有人,请建议我怎么做!!我猜这不太难得到,这在Java中是可能的,那么为什么不在nodejs中呢?
最佳答案
你能试着发送另一种二进制内容,比如一个文件,看看它是否有效吗?
最新的mqtt.js版本支持二进制有效负载https://github.com/adamvr/MQTT.js/issues/109
关于node.js - 如何使用nodeJS和protobufjs在MQTT中发送缓冲区或字节数组,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/22837899/