I'm receiving an error when connecting to my Mosquitto server in my flutter web project. I'm using the import for mqtt_browser_client.dart and the package mqtt_client.
My code follows the example, and I've checked, I am able to connect to my server from the same PC in MQTT Explorer. (becartpi:8080).
final client = MqttBrowserClient('ws://becArtPi', 'flutter');
void onPRessMQTTTest() async {
client.onDisconnected = onDisconnected;
client.onConnected = onConnected;
client.onSubscribed = onSubscribed;
client.logging(on: true);
client.port = 8080;
client.keepAlivePeriod = 20;
final connMess = MqttConnectMessage()
.withClientIdentifier('flutter')
.startClean() // Non persistent session for testing
.withWillQos(MqttQos.atLeastOnce);
print('EXAMPLE::Mosquitto client connecting....');
client.connectionMessage = connMess;
try {
await client.connect();
} on NoConnectionException catch (e) {
// Raised by the client when connection fails.
print('EXAMPLE::client exception - $e');
client.disconnect();
} on SocketException catch (e) {
// Raised by the socket layer
print('EXAMPLE::socket exception - $e');
client.disconnect();
} catch (e) {
print('MQTT Connection Error: $e');
}
client.updates!.listen((List<MqttReceivedMessage<MqttMessage?>>? c) {
final recMess = c![0].payload as MqttPublishMessage;
final pt =
MqttPublishPayload.bytesToStringAsString(recMess.payload.message);
print(
'EXAMPLE::Change notification:: topic is <${c[0].topic}>, payload is <-- $pt -->');
print('');
});
/// Check we are connected
if (client.connectionStatus!.state == MqttConnectionState.connected) {
print('EXAMPLE::Mosquitto client connected');
} else {
/// Use status here rather than state if you also want the broker return code.
print(
'EXAMPLE::ERROR Mosquitto client connection failed - disconnecting, status is ${client.connectionStatus}');
client.disconnect();
exit(-1);
}
const pubTopic = 'Dart/Mqtt_client/testtopic';
final builder = MqttClientPayloadBuilder();
client.publishMessage(pubTopic, MqttQos.exactlyOnce, builder.payload!);
}
void onDisconnected() {}
void onConnected() {
print(
'EXAMPLE::OnConnected client callback - Client connection was sucessful');
}
void onSubscribed(String topic) {}
EXAMPLE::Mosquitto client connecting....
1-2021-08-18 15:23:35.899 -- MqttClient::connect - keep alive is enabled with a value of 20 seconds
1-2021-08-18 15:23:35.900 -- MqttConnectionKeepAlive:: Initialised with a keep alive value of 20 seconds
1-2021-08-18 15:23:35.900 -- MqttConnectionKeepAlive:: Disconnect on no ping response is disabled
1-2021-08-18 15:23:35.901 -- MqttConnectionHandlerBase::connect - server ws://becArtPi/ws, port 8080
1-2021-08-18 15:23:35.901 -- SynchronousMqttBrowserConnectionHandler::internalConnect entered
1-2021-08-18 15:23:35.901 -- SynchronousMqttBrowserConnectionHandler::internalConnect - initiating connection try 0, auto reconnect in progress false
1-2021-08-18 15:23:35.902 -- SynchronousMqttBrowserConnectionHandler::internalConnect - calling connect
1-2021-08-18 15:23:35.902 -- MqttBrowserWsConnection::connect - entered
1-2021-08-18 15:23:35.903 -- MqttBrowserWsConnection::connect - WS URL is ws://becartpi:8080/ws
1-2021-08-18 15:23:35.906 -- MqttBrowserWsConnection::connect - connection is waiting
1-2021-08-18 15:23:36.068 -- MqttBrowserWsConnection::connect - websocket has erred
1-2021-08-18 15:23:36.069 -- SynchronousMqttBrowserConnectionHandler::internalConnect - connection complete
1-2021-08-18 15:23:36.069 -- SynchronousMqttBrowserConnectionHandler::internalConnect sending connect message
1-2021-08-18 15:23:36.069 -- MqttConnectionHandlerBase::sendMessage - MQTTMessage of type MqttMessageType.connect
Header: MessageType = MqttMessageType.connect, Duplicate = false, Retain = false, Qos = MqttQos.atMostOnce, Size = 0
Connect Variable Header: ProtocolName=MQIsdp, ProtocolVersion=3, ConnectFlags=Connect Flags: Reserved1=false, CleanStart=true, WillFlag=false, WillQos=MqttQos.atLeastOnce, WillRetain=false, PasswordFlag=false, UserNameFlag=false, KeepAlive=20
MqttConnectPayload - client identifier is : flutter
1-2021-08-18 15:23:36.072 -- SynchronousMqttBrowserConnectionHandler::internalConnect - pre sleep, state = Connection status is connecting with return code of noneSpecified and a disconnection origin of none
1-2021-08-18 15:23:41.098 -- SynchronousMqttBrowserConnectionHandler::internalConnect - post sleep, state = Connection status is connecting with return code of noneSpecified and a disconnection origin of none
1-2021-08-18 15:23:41.099 -- SynchronousMqttBrowserConnectionHandler::internalConnect - initiating connection try 1, auto reconnect in progress false
1-2021-08-18 15:23:41.099 -- SynchronousMqttBrowserConnectionHandler::internalConnect - calling connect
1-2021-08-18 15:23:41.099 -- MqttBrowserWsConnection::connect - entered
1-2021-08-18 15:23:41.100 -- MqttBrowserWsConnection::connect - WS URL is ws://becartpi:8080/ws
1-2021-08-18 15:23:41.100 -- MqttBrowserWsConnection::connect - connection is waiting
1-2021-08-18 15:23:41.276 -- MqttBrowserWsConnection::connect - websocket has erred
1-2021-08-18 15:23:41.276 -- SynchronousMqttBrowserConnectionHandler::internalConnect - connection complete
1-2021-08-18 15:23:41.276 -- SynchronousMqttBrowserConnectionHandler::internalConnect sending connect message
1-2021-08-18 15:23:41.277 -- MqttConnectionHandlerBase::sendMessage - MQTTMessage of type MqttMessageType.connect
Header: MessageType = MqttMessageType.connect, Duplicate = false, Retain = false, Qos = MqttQos.atMostOnce, Size = 21
Connect Variable Header: ProtocolName=MQIsdp, ProtocolVersion=3, ConnectFlags=Connect Flags: Reserved1=false, CleanStart=true, WillFlag=false, WillQos=MqttQos.atLeastOnce, WillRetain=false, PasswordFlag=false, UserNameFlag=false, KeepAlive=20
MqttConnectPayload - client identifier is : flutter
1-2021-08-18 15:23:41.277 -- SynchronousMqttBrowserConnectionHandler::internalConnect - pre sleep, state = Connection status is connecting with return code of noneSpecified and a disconnection origin of none
1-2021-08-18 15:23:46.318 -- SynchronousMqttBrowserConnectionHandler::internalConnect - post sleep, state = Connection status is connecting with return code of noneSpecified and a disconnection origin of none
1-2021-08-18 15:23:46.318 -- SynchronousMqttBrowserConnectionHandler::internalConnect - initiating connection try 2, auto reconnect in progress false
1-2021-08-18 15:23:46.319 -- SynchronousMqttBrowserConnectionHandler::internalConnect - calling connect
1-2021-08-18 15:23:46.319 -- MqttBrowserWsConnection::connect - entered
1-2021-08-18 15:23:46.319 -- MqttBrowserWsConnection::connect - WS URL is ws://becartpi:8080/ws
1-2021-08-18 15:23:46.320 -- MqttBrowserWsConnection::connect - connection is waiting
1-2021-08-18 15:23:46.487 -- MqttBrowserWsConnection::connect - websocket has erred
1-2021-08-18 15:23:46.487 -- SynchronousMqttBrowserConnectionHandler::internalConnect - connection complete
1-2021-08-18 15:23:46.487 -- SynchronousMqttBrowserConnectionHandler::internalConnect sending connect message
1-2021-08-18 15:23:46.488 -- MqttConnectionHandlerBase::sendMessage - MQTTMessage of type MqttMessageType.connect
Header: MessageType = MqttMessageType.connect, Duplicate = false, Retain = false, Qos = MqttQos.atMostOnce, Size = 21
Connect Variable Header: ProtocolName=MQIsdp, ProtocolVersion=3, ConnectFlags=Connect Flags: Reserved1=false, CleanStart=true, WillFlag=false, WillQos=MqttQos.atLeastOnce, WillRetain=false, PasswordFlag=false, UserNameFlag=false, KeepAlive=20
MqttConnectPayload - client identifier is : flutter
1-2021-08-18 15:23:46.488 -- SynchronousMqttBrowserConnectionHandler::internalConnect - pre sleep, state = Connection status is connecting with return code of noneSpecified and a disconnection origin of none
1-2021-08-18 15:23:51.521 -- SynchronousMqttBrowserConnectionHandler::internalConnect - post sleep, state = Connection status is connecting with return code of noneSpecified and a disconnection origin of none
1-2021-08-18 15:23:51.522 -- SynchronousMqttBrowserConnectionHandler::internalConnect failed
EXAMPLE::client exception - mqtt-client::NoConnectionException: The maximum allowed connection attempts ({3}) were exceeded. The broker is not responding to the connection request message (Missing Connection Acknowledgement?
1-2021-08-18 15:23:51.523 -- MqttConnectionHandlerBase::disconnect - entered
1-2021-08-18 15:23:51.523 -- MqttConnectionHandlerBase::_performConnectionDisconnect entered
Connection in MQTT Explorer which is connecting and receiving messages correctly.
mosquitto.log
1629283989: Socket error on client 8caab5860e74, disconnecting.
1629284712: Socket error on client <unknown>, disconnecting.
1629284717: Socket error on client <unknown>, disconnecting.
1629284722: Socket error on client <unknown>, disconnecting.
Check the websocket headers API setting you may be sending the wrong headers for your broker.
Have a look at the mqtt_server_client_websocket.dart file in the examples directory, the setting you want is client.websocketProtocols, look at the API for this.
Related
I am trying to call some external API hosted on azure from my web Api. The API is working fine on my local machine but when I deploy it IIS on server it starts throwing System.Net.Sockets.SocketException (10060).A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond. Although I have increased the request timeout to 5 minutes but connection is silently stopping after 21 seconds and throwing aforementioned exception.
Here is my code:
var telemetries = new TelemetryResponse();
var client = httpClientFactory.CreateClient("Lynx");
client.Timeout = TimeSpan.FromMinutes(5);
var httpResponseMessage = await client.GetAsync("vehicletelemetries/All?key=iLJIbAVXOnpKz5xyF0zV44yepu5OVfmZFhkHM7x");
if (httpResponseMessage.IsSuccessStatusCode)
{
string content = await httpResponseMessage.Content.ReadAsStringAsync();
telemetries = JsonConvert.DeserializeObject<TelemetryResponse>(content);
}
Exception I am getting is:
System.Net.Sockets.SocketException (10060): A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.
at System.Net.Sockets.Socket.AwaitableSocketAsyncEventArgs.ThrowException(SocketError error, CancellationToken cancellationToken)
at System.Net.Sockets.Socket.AwaitableSocketAsyncEventArgs.System.Threading.Tasks.Sources.IValueTaskSource.GetResult(Int16 token)
at System.Net.Sockets.Socket.g__WaitForConnectWithCancellation|277_0(AwaitableSocketAsyncEventArgs saea, ValueTask connectTask, CancellationToken cancellationToken)
at System.Net.Http.HttpConnectionPool.ConnectToTcpHostAsync(String host, Int32 port, HttpRequestMessage initialRequest, Boolean async, CancellationToken cancellationToken)
You got an error code:
WSAETIMEDOUT
10060
Connection timed out.
A connection attempt failed because the connected party did not properly respond after a period of time, or the established connection failed because the connected host has failed to respond.
https://learn.microsoft.com/en-us/windows/win32/winsock/windows-sockets-error-codes-2#WSAETIMEDOUT
Check your network connection, ip adress, port and maybe the connection got blocked from a firewall.
Hi guys the culprit was the proxy and we have to configure our HttpClient with proxy while creating it/registering in the DI container. I have registered the HttpClient in DI like this.
var proxySettings = new ProxySetting();
Configuration.Bind(nameof(ProxySetting), proxySettings);
services.AddHttpClient("Lynx", client =>
{
client.BaseAddress = new Uri(Configuration.GetSection("LynxUrl").Value);
}).ConfigurePrimaryHttpMessageHandler(() => new HttpClientHandler { Proxy = new MyProxy(proxySettings)});
And my proxy code is
public class MyProxy : IWebProxy
{
private readonly ProxySetting _proxySetting;
public MyProxy(ProxySetting proxySetting)
{
_proxySetting = proxySetting;
}
public ICredentials Credentials
{
//get { return new NetworkCredential("username", "password"); }
get { return new NetworkCredential(_proxySetting.UserName, _proxySetting.Password,_proxySetting.Domain); }
set { }
}
public Uri GetProxy(Uri destination)
{
return new Uri(_proxySetting.ProxyUrl);
}
public bool IsBypassed(Uri host)
{
return false;
}
}
It has resolved my problem completely.
I am trying to make webapp over flutter which will connect to HIVE broker. I took the broker name from the official website, set the port number to 8000 just like mentioned there and still get the error message as below:
error is mqtt-client::NoConnectionException: The maximum allowed connection attempts ({1}) were exceeded. The broker is not responding to the connection request message (Missing Connection Acknowledgement?
I really have no clue how to proceed. Can someone please help?
Below is my code:
MqttBrowserClient mq = MqttBrowserClient(
'wss://broker.mqttdashboard.com:8000', '',
maxConnectionAttempts: 1);
/*
MqttBrowserClient mq = MqttBrowserClient('ws://test.mosquitto.org', 'client-1',
maxConnectionAttempts: 1);
*/
class mqttService {
Future<MqttBrowserClient?> connectToServer() async {
try {
final connMess = MqttConnectMessage()
.withClientIdentifier('clientz5tWzoydVL')
.authenticateAs('a14guguliye', 'z5tWzoydVL')
.withWillTopic('willtopic')
.withWillMessage('My Will message')
.startClean() // Non persistent session for testing
.withWillQos(MqttQos.atLeastOnce);
mq.port = 1883;
mq.keepAlivePeriod = 50;
mq.connectionMessage = connMess;
mq.websocketProtocols = MqttClientConstants.protocolsSingleDefault;
mq.onConnected = onConnected;
var status = await mq.connect();
return mq;
} catch (e) {
print("error is " + e.toString());
mq.disconnect();
return null;
}
}
}
That port 8000 may be open but the HiveMQ broker may not be listening.
Make sure that the broker is fully booted and binds to that IP:Port combo.
In the HiveMQ broker startup output, you should see something similar to:
Started Websocket Listener on address 0.0.0.0 and on port 8000
If needed, the HiveMQ Broker configuration documentation is here.
You can use the public HiveMQ MQTT Websocket demo client to test your connection to make sure it's not a local code issue.
As a last option, use Wireshark to monitor MQTT traffic with a filter of tcp.port == 8000 and mqtt
I have this pattern:
channel ESANTE_MPI_CREATE_PATIENT_LISTENER (with a MLLP listener) calls channel ESANTE_MPI_CREATE_PATIENT that calls a TCP destination.
If connection cannot be done in the TCP destination inside ESANTE_MPI_CREATE_PATIENT then this channel reports an error for this destination:(ERROR: ConnectException: Connection refused (Connection refused))
The response transformer does not seem to be called (which is normal as there is no response).
I wonder how I can report the error back to the calling channel ESANTE_MPI_CREATE_PATIENT_LISTENER ?
PS: When tcp destination responds, then I use the response transformer to parse the received frame and create a response message (json error/ok) for the calling channel. Everything works fine here.
My question ends up with: How to trap a Connection refused in a TCP destination to create a response message.
I finally managed this by using the postprocessor script in ESANTE_MPI_CREATE_PATIENT to get the response of the connector and then force a message.
// fake error message prepared for connection refused.
// we put this as the response of the channel destination in order to force a understandable error message.
const sErrorMsg = {
status: "error",
error: "connection refused to eSanté MPI"
};
const TCP_CONNECTOR_ESANTE_MPI_RANK = 2; // WARNING: be sure to take the correct connector ID as displayed into destination.
const TCP_CONNECTOR_ESANTE_MPI_DNAME = 'd' + TCP_CONNECTOR_ESANTE_MPI_RANK; // WARNING: be sure to take the correct connector ID as displayed into destination.
/*
var cms = message.getConnectorMessages(); // returns message but as Immutable
responses. not what we want: we use responseMap instead.
var key = TCP_CONNECTOR_ESANTE_MPI_RANK;
logger.debug(" Response Data=" + cms.get(key).getResponseData());
logger.debug(" Response Data0=" + cms.get(key).getResponseError());
logger.debug(" Response Data1=" + cms.get(key).getResponseData().getError());
logger.debug(" Response Data2=" + cms.get(key).getResponseData().getMessage());
logger.debug(" Response Data3=" + cms.get(key).getResponseData().getStatusMessage());
logger.debug(" Response Data4=" + cms.get(key).getResponseData().getStatus());
*/
var responseMPI = responseMap.get(TCP_CONNECTOR_ESANTE_MPI_DNAME); // return a mutable reponse :-)
if (responseMPI.getStatus()=='ERROR' &&
responseMPI.getStatusMessage().startsWith('ConnectException: Connection refused')) {
// build a error message for this dedicated case
logger.error("connection refused detected");
responseMPI.setMessage(JSON.stringify(sErrorMsg)); // force the message to be responsed.
}
return;
Exception while connecting to the server: A connection attempt failed because the connected party did not properly respond after a period of time, or an established connection failed because the connected host has failed to respond.
1.) able to ping the server
2.) telnet smtp.office365.com 587 respond as expected.
public ConnectSmtpServer()
{
using MailKit.Net.Smtp;
string _SmtpServer = "smtp.office365.com";
int _portNumber = 587;
Console.WriteLine("Welcome!");
using (SmtpClient smtp = new SmtpClient())
{
try
{
smtp.Timeout = 30 * 1000;
smtp.Connect(_SmtpServer, _portNumber, SecureSocketOptions.Auto);
Console.WriteLine("Test smtp connection using MailKit.Net !");
smtp.Connect(_SmtpServer, _portNumber, SecureSocketOptions.Auto);
Console.WriteLine();
}
}
}
We are trying to create a Kafka client using Deno and TCP sockets. As a first step, we are trying to ping a broker we have running on a docker instance using the below code:
import {
Client,
Packet,
Event,
} from 'https://deno.land/x/tcp_socket#0.0.1/mods.ts';
const client = new Client({
hostname: 'localhost',
port: 9092,
});
for (let i = 0; i < 2; i++) {
// Connection open
client.on(Event.connect, (client: Client) => {
console.log('Connect', client.conn?.remoteAddr);
});
// Receive message
client.on(Event.receive, (client: Client, data: Packet) => {
console.log('Receive', data.toString());
});
// Connection close
client.on(Event.close, (client: Client) => {
console.log('Close');
});
// Handle error
client.on(Event.error, (e) => {
console.error(e);
});
// Do
await client.connect(); // Start client connect
await client.write('Hello World'); // Send string data
await client.write(new Uint8Array()); // Send Uint8Array data
client.close();
}
We are successfully pinging the broker, but receive the following error:
[2021-08-13 00:20:36,472] WARN Unexpected error from /172.20.0.1; closing connection (org.apache.kafka.common.network.Selector)
org.apache.kafka.common.network.InvalidReceiveException: Invalid receive (size = 1214606444 larger than 104857600)
at org.apache.kafka.common.network.NetworkReceive.readFromReadableChannel(NetworkReceive.java:91)
at org.apache.kafka.common.network.NetworkReceive.readFrom(NetworkReceive.java:71)
at org.apache.kafka.common.network.KafkaChannel.receive(KafkaChannel.java:169)
at org.apache.kafka.common.network.KafkaChannel.read(KafkaChannel.java:150)
at org.apache.kafka.common.network.Selector.pollSelectionKeys(Selector.java:365)
at org.apache.kafka.common.network.Selector.poll(Selector.java:313)
at kafka.network.Processor.poll(SocketServer.scala:494)
at kafka.network.Processor.run(SocketServer.scala:432)
at java.lang.Thread.run(Thread.java:745)
[2021-08-13 00:28:19,708] INFO [Group Metadata Manager on Broker 0]: Removed 0 expired offsets in 0 milliseconds. (kafka.coordinator.GroupMetadataManager)
We understand that this is due to a protocol issue and are trying to determine what the best way forward is to address this issue. Any help would be greatly appreciated