clap-logflag 0.2.1

This library can be used to add a `--log` flag to clap based command line applications that allows users to configure logging from the command line. It can log to stderr, files and syslog, powered by the fern logging backend.
Documentation 
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//! This example is not a real world example, it is used in our integration tests as a test binary.

use clap::Parser;
use clap_logflag::{LogDestinationConfig, LoggingConfig};
use log::LevelFilter;

#[derive(Debug, Parser)]
struct CliArgs {
    /// Use this to add the log flags to your application
    #[clap(flatten)]
    log: clap_logflag::LogArgs,

    /// A real cli app would likely hardcode a default level instead of allowing users to pass it in.
    /// We're just doing that here to make this example useful for our integration tests.
    #[arg(long)]
    default_level: LevelFilter,
}

fn main() {
    let args = CliArgs::parse();

    // Initialize logging with the flags from clap
    clap_logflag::init_logging!(
        args.log
            // If no `--log` arguments are present, log to stderr but only log warnings and errors.
            .or_default(LoggingConfig::new(vec![LogDestinationConfig {
                destination: clap_logflag::LogDestination::Stderr,
                level: Some(LevelFilter::Warn),
            },],)),
        args.default_level
    );

    log::trace!("Some trace log");
    log::debug!("Some debug log");
    log::info!("Some info log");
    log::warn!("Some warn log");
    log::error!("Some error log");
}