viperus

̶g̶o̶ rust configuration with fangs!

viperus is an (in)complete configuration solution for Rust applications. inspired heavly inspired by the wonderful go package https://github.com/spf13/viper I have already said that it is incomplete? use at your own risk. ;-)

no Go projects are built using Viperus :-)

What is Viperus?

handle some types of configuration needs and formats. It supports:

setting defaults
reading from JSON, TOML, YAML, envfile config files
reading from environment variables
reading from Clap command line flags
setting explicit values

Why Viperus?

beacuse I was migrating some go apps... and a was missing Viper ease of use :-)

Viperus uses the following decreasing precedence order.

explicit call to add
clap flag
env
config
default

Viperus merge configuration from toml,dotenv,json,yaml files and clap options in sigle typed hash structure. with defaults, and type checking

you can create a stand alone Viperus object or "enjoy" a global instance ( thread safe protected with a mutex) via shadow functions load_file|get|add|load_clap that are routed to the static instance.

     viperus::load_file(".env", viperus::Format::ENV).unwrap();
     let ok=viperus::get::<bool>("TEST_BOOL").unwrap();

by the way , Yes I konw globals are evil. but as I was inspired by the go package viper.... if you dislike globals you can opt-out disabling in your cargo.toml the feature "global".

logging/debug

the crate uses log facade , and test the env_logger you can set the env variable to RUST=viperus=[DEBUG LEVEL] with [DEBUG LEVEL] = info|warning|debug

Example

you can find some integration tests in the test dir and also in the example forlder you can run example with cargo

cargo run --example cli-clap-yaml -- 
cargo run --example cli-clap-yaml -- -u http://nowhere/api/v1

the first run print the value from the example.yaml file the second from the cli arg



 let matches = App::new("My Super Program")
                          .arg(Arg::with_name("v")
                               .short("v")
                               .multiple(true)
                               .help("Sets the level of verbosity"))
                          .get_matches();   

let mut v = Viperus::new();

//enable clap
v.load_clap(matches);
//enable a yaml json toml file
v.load_file(&path!(".","assets","test.yaml"), Format::YAML).unwrap();
v.load_file(&path!(".","assets","test.json"), Format::JSON).unwrap();
v.load_file(&path!(".","assets","test.toml"), Format::TOML).unwrap();

//link the "v" clap option to the key "verbose"
v.bond_clap("v","verbose");


//add an explicit overload 
v.add("service.url", String::from("http://example.com"));
debug!("final {:?}", v);

//get a typed key
let s: &str = v.get("service.url").unwrap();
assert_eq!("http://example.com", s);

//get a bool from configs or app args
let fVerbose=v.get::<bool>("verbose").unwrap();
assert_eq!(true, fVerbose);

Todo