文盘Rust -- 给程序加个日志

   let sys_file = FileAppender::builder()
       .encoder(Box::new(PatternEncoder::new("{d} - {m}{n}")))
       .build("logs/sys.log")
       .unwrap();
   let business_file = FileAppender::builder()
       .encoder(Box::new(PatternEncoder::new("{d} - {m}{n}")))
       .build("logs/business.log")
       .unwrap();

   let stdout = ConsoleAppender::builder().build();

   let config = Config::builder()
       .appender(Appender::builder().build("stdout", Box::new(stdout)))
       .appender(Appender::builder().build("sys", Box::new(sys_file)))
       .appender(Appender::builder().build("business", Box::new(business_file)))
       .logger(
           Logger::builder()
               .appender("sys")
               .build("syslog", LevelFilter::Info),
       )
       .logger(
           Logger::builder()
               .appender("business")
               .build("businesslog", LevelFilter::Info),
       )
       .build(
           Root::builder()
               .appender("stdout")
               .appender("file_out")
               .build(LevelFilter::Info),
       )
       .unwrap();

   let _ = log4rs::init_config(config).unwrap();

 pub fn new_use_sys_log_cmd() -> Command<'static> {
     clap::Command::new("syslog").about("append to syslog")
 }
 
 pub fn new_use_business_log_cmd() -> Command<'static> {
     clap::Command::new("businesslog").about("append to business log")
 }