Always exclude certain dependencies from logging

[kornelski]

I'd like to have RUST_LOG env variable to work as usual, except never log anything from a couple of noisy dependencies.

I thought this would do the trick:

        let _ = env_logger::Builder::from_default_env()
            .filter(Some("html5ever"), log::LevelFilter::Off)
            .filter(Some("tantivy"), log::LevelFilter::Off)
            .try_init();

but it seems that RUST_LOG=debug enables debug output even for the dependencies I'm trying to filter out.

Is there a way to gracefully combine env vars and explicit filters, with my filter() calls taking precedence?

[slientgoat]

RUST_LOG=DEBUG,html5ever=off,tantivy=off

[kornelski]

I know it's possible to set it manually every time, but my whole point is that I would like to avoid having to do this the long way, and provide a better default. In other words I'd like:

• RUST_LOG=debug to behave like RUST_LOG=debug,html5ever=off,tantivy=off, and ideally
• RUST_LOG=debug,html5ever=on to behave like RUST_LOG=debug,html5ever=on,tantivy=off