1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35

use fern::colors::{Color, ColoredLevelConfig};

pub fn set_up_logging() {
    // configure colors for the whole line
    let colors_line = ColoredLevelConfig::new()
        .error(Color::Red)
        .warn(Color::Yellow)
        // we actually don't need to specify the color for debug and info, they are white by default
        .info(Color::White)
        .debug(Color::White)
        // depending on the terminals color scheme, this is the same as the background color
        .trace(Color::BrightBlack);

    // configure colors for the name of the level.
    // since almost all of them are the same as the color for the whole line, we
    // just clone `colors_line` and overwrite our changes
    let colors_level = colors_line.info(Color::Green);
    // here we set up our fern Dispatch
    fern::Dispatch::new()
        .format(move |out, message, record| {
            out.finish(format_args!(
                "{color_line}[{level}{color_line}] {message}\x1B[0m",
                color_line = format_args!(
                    "\x1B[{}m",
                    colors_line.get_color(&record.level()).to_fg_str()
                ),
                level = colors_level.color(record.level()),
                message = message,
            ));
        })
        .level(log::LevelFilter::Info)
        .chain(std::io::stdout())
        .apply()
        .unwrap();
}