GUI: Daemon "info" level logs when starting it

[darosior]

On mainnet it takes a few minutes for my bitcoind to load the watchonly wallet. Therefore the GUI stays stuck at the following screen with no apparent progress.

I think it would be nice to display the daemon info-level logs to let the user know there is actual progress.

[jp1ac4]

I think it would be nice to display the daemon info-level logs to let the user know there is actual progress.

I'm not sure how best to approach this. Would it be reading the stdout somehow and displaying that? Or perhaps adding a log dispatcher that filters for info-level logs?

[darosior]

I was thinking of a log dispatcher, but i'm not sure either. @edouardparis any idea?

[edouardparis]

The way I see it, in gui/src/logger.rs:
Make a struct wrapping a mpsc channel sender, lets call it LogStream
make it implement tracing_subsriber::Layer
something like:

struct LogStream {
    sender: mpsc::Sender<String>,
}

impl<S> Layer<S> for LogStream
where
    S: Subscriber + for<'a> tracing_subscriber::registry::LookupSpan<'a>,
{
    fn on_event(&self, event: &Event<'_>, _ctx: Context<'_, S>) {
        if let Some(message) = event.message().map(ToString::to_string) {
            let _ = self.sender.send(message);
        }
    }
}

   let (sender, receiver) = mpsc::channel::<String>();
    tracing_subscriber::registry().with(LogStream{ sender });

the mpsc channel receiver is then passed to loader to listen from it in a subscription.