yaml2json 0.1.2

use std::fs;
use std::io::{self, Read};

use anyhow::{Context, Result};
use clap::{Arg, Command};

fn main() -> Result<()> {
    let app = Command::new(env!("CARGO_PKG_NAME"))
        .version(env!("CARGO_PKG_VERSION"))
        .about(env!("CARGO_PKG_DESCRIPTION"))
        .arg(
            Arg::new("pretty")
                .help("pretty print the JSON")
                .short('p')
                .long("pretty"),
        )
        .arg(
            Arg::new("input")
                .help("the YAML to convert")
                .index(1)
                .default_value("-"),
        );
    let matches = app.get_matches();
    let input_src = matches.value_of("input").unwrap();
    let input_buf = match input_src {
        "-" => {
            let mut input_buf = String::new();
            io::stdin()
                .read_to_string(&mut input_buf)
                .with_context(|| "failed to collect stdin")?;
            input_buf
        }
        input => fs::read_to_string(input)
            .with_context(|| format!("failed to collect from input: {}", input))?,
    };

    let value = serde_yaml::from_str::<serde_json::Value>(&input_buf)
        .with_context(|| format!("parsing YAML from {} failed", input_src))?;

    if matches.is_present("pretty") {
        serde_json::to_writer_pretty(io::stdout(), &value)
    } else {
        serde_json::to_writer(io::stdout(), &value)
    }
    .with_context(|| "JSON serialization and/or stdout streaming failed")?;

    Ok(())
}

#[cfg(test)]
mod test {
    use super::*;

    #[test]
    fn test_app() {
        assert!(true)
    }
}