Hands-On Microservices with Rust

How to add subcommands

Some popular applications, such as cargo and docker, use subcommands to provide multiple commands inside a single binary. We can also support subcommands with the clap crate. A microservice might have two commands: one to run the server and one to generate a secret for the HTTP cookies. Take a look at the following code:

let matches = App::new("Server with keys")    .setting(AppSettings::SubcommandRequiredElseHelp)
    .subcommand(SubCommand::with_name("run")
        .about("run the server")
        .arg(Arg::with_name("address")
            .short("a")            .long("address")            .takes_value(true)
            .help("address of the server"))    .subcommand(SubCommand::with_name("key")
        .about("generates a secret key for cookies")))    .get_matches();

Here, we have used two methods. ...