cli-app-base/examples/minimal.rs

//! This is a minimal example with a config file and logging

#[macro_use]
extern crate serde_derive;
#[macro_use]
extern crate log;

use clappconfig::AppConfig; // Must be in scope so the trait methods may be used
use failure::Fallible;

#[derive(Serialize, Deserialize, Debug, Default)]
#[serde(default)]
struct Config {
    foo: u32,
    bar: u32,
}

impl AppConfig for Config {
    // We want init() to just return the config struct
    type Init = Config;

    /// Logging - we do not have a config option for this, so just return a default value
    fn logging(&self) -> &str {
        "info"
    }

    /// Finalize config (this is called inside `init()`)
    fn configure<'a>(self, _clap: &clap::ArgMatches<'a>) -> Fallible<Self::Init> {
        Ok(self)
    }
}

fn main() -> Fallible<()> {
    let cfg = Config::init("Foo Example", "examples/foo.json", None)?;

    trace!("Trace message");
    debug!("Debug message");
    info!("Info message");
    warn!("Warn message");
    error!("Error message");

    println!("Welcome to foo, config is:\n{:#?}", cfg);

    Ok(())
}