Add license check to Intercepting Publish on server

[dgxhubbard]

I would like to add a license check to InterceptingPublishAsync and if the license has not been entered then reject publish to
subscribers if license is not valid. First is InterceptingPublishAsync the right place to do this, second how to tell publisher that
license needs to be entered.

[dgxhubbard]

I think what I need is in this article https://github.com/dotnet/MQTTnet/wiki/Server#intercepting-application-messages

[SeppPenner]

You can check https://github.com/dotnet/MQTTnet/blob/master/Samples/Server/Server_Intercepting_Samples.cs as the Wiki is for version 3 only.

1. Yes, it is the right place.
2. You need to set a property of the eventArgs to true. Not sure how it's called though. Something like this:

E.g.

public void InterceptPublishAsync (PublishEventArgs args)
{
    var someLicenseCheck = true;
    if (!someLicenseCheck)
    {
        args.Publish = false;
    }
}

[dgxhubbard]

Thank you. That worked perfectly.

[SeppPenner]

Just for reference, it's InterceptingPublishEventArgs and ProcessPublish = false. Check out

MQTTnet/Source/MQTTnet.Server/Events/InterceptingPublishEventArgs.cs

Line 39 in 63d8518

public bool ProcessPublish { get; set; } = true;

.

I guess, this can be closed now.