[feat] only allow valid dirs as 1st arg

src/main.rs

@@ -1,6 +1,7 @@
 use std::{
     net::{IpAddr, SocketAddr},
     num::NonZeroUsize,
+    path::PathBuf,
     thread::available_parallelism,
 };
 
@@ -11,8 +12,8 @@ use clap::{crate_name, crate_version, Parser};
 #[clap(name = crate_name!(), version = crate_version!())]
 struct Args {
     /// Directory to expose
-    #[clap(default_value = ".")]
-    dir: String,
+    #[clap(default_value = ".", value_parser = parse_valid_dir)]
+    dir: PathBuf,
 
     /// IP address to use
     #[clap(default_value = "0.0.0.0")]
@@ -23,6 +24,15 @@ struct Args {
     port: u16,
 }
 
+fn parse_valid_dir(dir: &str) -> Result<PathBuf, String> {
+    let path = std::path::Path::new(dir);
+    if path.is_dir() {
+        Ok(path.to_path_buf())
+    } else {
+        Err(format!("{} is not a valid directory", path.display()))
+    }
+}
+
 #[actix_web::main]
 async fn main() -> std::io::Result<()> {
     let args = Args::parse();
@@ -30,7 +40,10 @@ async fn main() -> std::io::Result<()> {
     let dir = args.dir;
     let sock = SocketAddr::new(args.ip, args.port);
 
-    println!("Starting HTTP server on {sock} exposing dir {dir}");
+    println!(
+        "Starting HTTP server on {sock} exposing dir {}",
+        dir.display()
+    );
 
     HttpServer::new(move || {
         App::new().service(