Hyper(tracing) logging in env_logger maner?

[jofas]

@davemilter

Any way to redirect tracing data to stdout, if take into consideration that I do not directly depend on hyper, only via reqwest?

You must enable a Subscriber to do anything with the log messages created by tracing, like printing them to stdout. The tracing-subscriber crate provides a good Subscriber. Re-using the RUST_LOG environment variable and showing the hyper logs should be as easy as adding the following to your code:

Cargo.toml:

[dependencies]
tracing-subscriber = { version = "^0.3.16", features = ["env-filter"] }

main.rs:

fn main() {
    tracing_subscriber::fmt::init();
}

Here some more background:

Enabling Tracing Logging for a Specific Module

tracing alone isn't emitting any log messages without a Subscriber that determines how the log messages should be displayed. The common choice of implementation can be found in the tracing-subscriber crate. Here is how you can use tracing-subscriber to restrict log-messages printed in stdout to a specific module: /* [dependencies] tracing = "*" tracing-subscriber = { version = "^0.3.16", features = ["env-filter"] } */ mod foo { pub fn hello_logger() { tracing::info!("hello from foo"…