RSCONFIG

Simple configuration library to help programs manage their config.

Importing

If just using RSCONFIG, you can do this:

[dependencies]

rsconfig = "0.1.0" # replace with latest version

Examples

CommandlineConfig

use rsconfig::CommandlineConfig;
use std::{env, fs, io::Result};

// our config class that we can expand upon to add different values
// to expand upon it, simply add more fields and update the import function(s)
#[derive(Debug)]
struct TestConfig {
    test: bool
}

impl CommandlineConfig for TestConfig {
    fn from_env_args(args: Vec<String>) -> Self {
        // check if commandline args contains --test
        Self { test: args.contains(&"test".to_string()) }
    }
}


fn main() {
    // fetch commandline args
    let args: Vec<String> = env::args().collect();

    // load config from commandline args
    let mut config = TestConfig::from_env_args(args);

    // should output TestConfig { test: true } if --test is in the command
    // otherwise, it will print TestConfig { test: false }
    println!("{:?}", config);

    // you can change the value of the config
    config.test = !config.test;
}

YamlConfig

// import YamlConfig and files
// files has some useful load functions
use rsconfig::YamlConfig;
use rsconfig::files;

use yaml_rust;

// our config class that we can expand upon to add different values
// to expand upon it, simply add more fields and update the import function(s)
#[derive(Debug)]
struct TestConfig {
    test: bool
}

impl YamlConfig for TestConfig {
    fn from_yaml(yaml: Vec<yaml_rust::Yaml>) -> Self {
        // fetch "test" value of the first yaml document using yaml_rust crate
        // NOTE: this code is not error-safe, will panic if the correct file formatting is not used
        Self { test: *&yaml[0]["test"].as_bool().unwrap() }
    }

    fn save_yaml(&self, path: &str) -> Result<()> {

        // might want to do this differently for config with more fields
        let mut data = "test: ".to_string();

        // add the value to the file data
        data.push_str(self.test.to_string().as_str());

        // write to the file
        fs::write(path, data).unwrap();

        // return an Ok result
        // required because fs::write could fail, which would pass on an Err(()).
        Ok(())
    }
}


fn main() {
    /*
    NOTE: for a situation where you don't know the filetype,
    you can impl FileConfig and use files::load_from_file, which
    works for multiple different types of files.
    */
    let mut config: TestConfig = files::load_from_yaml();

    // should output TestConfig { test: true } if test: true in the yml file
    // otherwise, it will print TestConfig { test: false }
    println!("{:?}", config);

    // you can change the value of the config
    config.test = !config.test;
}

JsonConfig

// import JsonConfig and files
// files has some useful load functions
use rsconfig::JsonConfig;
use rsconfig::files;

use serde_json;

// our config class that we can expand upon to add different values
// to expand upon it, simply add more fields and update the import function(s)
#[derive(Debug)]
struct TestConfig {
    test: bool
}

impl JsonConfig for TestConfig {
    fn from_json(val: serde_json::Value) -> Self {
        // look for "test" val
        // NOTE: this code is not error-safe, will panic if the json does not contain a bool named "test"
        Self { test: val["test"].as_bool().unwrap() }
    }

    fn save_json(&self, path: &str) -> io::Result<()> {
        // convert to json pretty format and save
        let data = serde_json::to_string_pretty(&Value::from(self.test)).unwrap();
        fs::write(path, data).unwrap();

        Ok(())
    }
}

fn main() {
    /*
    NOTE: for a situation where you don't know the filetype,
    you can impl FileConfig and use files::load_from_file, which
    works for multiple different types of files.
    */
    let mut config: TestConfig = files::load_from_json();

    // should output TestConfig { test: true } if {"test": true} in the json file
    // otherwise, it will print TestConfig { test: false }
    println!("{:?}", config);

    // you can change the value of the config
    config.test = !config.test;
}