pub fn init_logging(
logging: &LoggingConfig,
directive: Option<String>,
) -> Result<(), String>Expand description
Installs the process-wide tracing subscriber from [logging].
Every knob is validated before anything is installed, and an unknown value
is an error the caller prints and exits on rather than a silent fallback —
the same reasoning as [build_env_filter]: a certificate authority running
at a log level or to a destination its operator did not ask for is worse
than one that refuses to start and says why.