How to route Messages

[dotnet]

How to route Messages

[chkr1011]

Hi,
your code likes fine so far. For your case you need one server and several clients. So you need a parameter to distinguish the clients in your client code (i.e. parameter).

It is not possible to send a message directly to a special client. You can only publish a message to the server. Depending on the topic several clients can subscribe to that topic. You can build your own patterns based on it. So if you need to send a message to client1 you can send them to something like client/1/messages and client1 is the only one who has subscribed that topic. For example with client/1/+.

Please find more information here: http://www.hivemq.com/blog/mqtt-essentials-part-5-mqtt-topics-best-practices

If you have more questions please let me know.

Best regards
Christian

[Zuendelmeister]

Hi @chkr1011,
thanks for your fast response and the link.
I tried out the following:
Client_2:

var applicationMessage = new MqttApplicationMessage(
"client/1/messages",
Encoding.UTF8.GetBytes("Hello World"),
MqttQualityOfServiceLevel.ExactlyOnce,
false
);
Console.WriteLine("Sending");
client.PublishAsync(applicationMessage);

And Client_1:

client.Connected += async (s,e) =>
{
Console.WriteLine("### CONNECTED WITH SERVER ###");
await client.SubscribeAsync(new List
{
new TopicFilter("client/1/+", MqttQualityOfServiceLevel.AtLeastOnce)
});

And it worked like a charm. Thank you so much!
But to my second question: Can the server log somehow the incomming messages?

Best regards,
Zuendelmeister

[chkr1011]

You can use the MqttTrace class to attach a handler for general trace and debug messages. But there you will not see the content of the messages etc.
Or do you need something different?

[Zuendelmeister]

I was hoping to log all incomming and outgoing messages in the broker program. But if thats not possible I have to live without it. Thanks.

[chkr1011]

I can add it if you like. It should be not a huge change. You need the ApplicationMessages and the sending ClientId only? I assume you don't need the low level packages or?

[Zuendelmeister]

Gread that would be awsome.
What I need is the ApplicationMessage, the ClientId, the MqttQualityOfServiceLevel and the topic. The retain information could come in handy too but this is not important.
Thank you =)

[chkr1011]

OK this what you need is all part of the ApplicationMessage excluding the ClientId. I will add a event which gives you both. Give me a few days to implement it.

[Zuendelmeister]

Perfect =)

[chkr1011]

Hi, I added this feature to master. Please test it and tell me if it fits your needs. It is a new event at the MqttServer available.

[chkr1011]

I released a new version. If you need something please let me know (open the ticket).