basic clap cli

Cargo.toml

@@ -20,6 +20,7 @@ time = "0.1"
 evmjit = { path = "rust-evmjit", optional = true }
 ethash = { path = "ethash" }
 num_cpus = "0.2"
+clap = { version = "1.5", features = ["yaml"] }
 
 [features]
 jit = ["evmjit"]

src/bin/client/cli.yml

@@ -0,0 +1,14 @@
+# NOTE! use 4 spaces instead of tabs. 
+# rust yml parser do not support tabs
+
+name: parity
+version: 0.1.0
+about: Ethereum rust implementation
+
+args:
+    - VERBOSITY:
+        long: verbosity
+        help: Logging verbosity (RUST_LOG)
+        takes_value: true
+
+

src/bin/client/main.rs

@@ -1,11 +1,13 @@
+#[macro_use]
+extern crate clap;
+
 extern crate ethcore_util as util;
 extern crate ethcore;
 extern crate rustc_serialize;
 extern crate log;
 extern crate env_logger;
 
 use std::io::stdin;
-use std::env;
 use log::{LogLevelFilter};
 use env_logger::LogBuilder;
 use util::*;
@@ -15,19 +17,22 @@ use ethcore::ethereum;
 use ethcore::blockchain::CacheSize;
 use ethcore::sync::*;
 
-fn setup_log() {
+fn setup_log(filter: Option<&str>) {
 	let mut builder = LogBuilder::new();
 	builder.filter(None, LogLevelFilter::Info);
 
-	if env::var("RUST_LOG").is_ok() {
-		builder.parse(&env::var("RUST_LOG").unwrap());
+	if let Some(f) = filter {
+		builder.parse(f);
 	}
 
 	builder.init().unwrap();
 }
 
 fn main() {
-	setup_log();
+	let yaml = load_yaml!("cli.yml");
+	let matches = clap::App::from_yaml(yaml).get_matches();
+	setup_log(matches.value_of("VERBOSITY"));
+
 	let spec = ethereum::new_frontier();
 	let mut service = ClientService::start(spec).unwrap();
 	let io_handler  = Box::new(ClientIoHandler { client: service.client(), timer: 0, info: Default::default() });