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//! Demonstrates how to set the default log level for the logger to something other than the default
//! (`ErrorLevel`). This is done with multiple subcommands, each with their own verbosity level.
use clap::{Parser, Subcommand};
use clap_verbosity_flag::{
DebugLevel, ErrorLevel, InfoLevel, OffLevel, TraceLevel, Verbosity, WarnLevel,
};
#[derive(Debug, Parser)]
struct Cli {
#[command(subcommand)]
command: Command,
}
#[derive(Debug, Subcommand)]
enum Command {
Off {
#[command(flatten)]
verbose: Verbosity<OffLevel>,
},
Error {
#[command(flatten)]
verbose: Verbosity<ErrorLevel>,
},
Warn {
#[command(flatten)]
verbose: Verbosity<WarnLevel>,
},
Info {
#[command(flatten)]
verbose: Verbosity<InfoLevel>,
},
Debug {
#[command(flatten)]
verbose: Verbosity<DebugLevel>,
},
Trace {
#[command(flatten)]
verbose: Verbosity<TraceLevel>,
},
}
impl Command {
fn log_level_filter(&self) -> log::LevelFilter {
match self {
Command::Off { verbose } => verbose.log_level_filter(),
Command::Error { verbose } => verbose.log_level_filter(),
Command::Warn { verbose } => verbose.log_level_filter(),
Command::Info { verbose } => verbose.log_level_filter(),
Command::Debug { verbose } => verbose.log_level_filter(),
Command::Trace { verbose } => verbose.log_level_filter(),
}
}
}
fn main() {
let cli = Cli::parse();
env_logger::Builder::new()
.filter_level(cli.command.log_level_filter())
.init();
log::error!("Engines exploded");
log::warn!("Engines smoking");
log::info!("Engines exist");
log::debug!("Engine temperature is 200 degrees");
log::trace!("Engine subsection is 300 degrees");
}