feat(cli): add more convenient SocketAddr argument parsing (#757)

bin/reth/src/node/mod.rs

@@ -8,6 +8,7 @@ use crate::{
     util::{
         chainspec::{chain_spec_value_parser, ChainSpecification},
         init::{init_db, init_genesis},
+        socketaddr_value_parser,
     },
     NetworkOpts,
 };
@@ -65,7 +66,7 @@ pub struct Command {
     /// Enable Prometheus metrics.
     ///
     /// The metrics will be served at the given interface and port.
-    #[clap(long, value_name = "SOCKET")]
+    #[arg(long, value_name = "SOCKET", value_parser = socketaddr_value_parser)]
     metrics: Option<SocketAddr>,
 
     /// Set the chain tip manually for testing purposes.

bin/reth/src/util/mod.rs

@@ -2,6 +2,7 @@
 use reth_primitives::{BlockHashOrNumber, H256};
 use std::{
     env::VarError,
+    net::{SocketAddr, ToSocketAddrs},
     path::{Path, PathBuf},
     str::FromStr,
 };
@@ -37,6 +38,29 @@ pub(crate) fn hash_or_num_value_parser(value: &str) -> Result<BlockHashOrNumber,
     }
 }
 
+/// Parse [SocketAddr]
+pub(crate) fn socketaddr_value_parser(value: &str) -> Result<SocketAddr, eyre::Error> {
+    const DEFAULT_DOMAIN: &str = "localhost";
+    const DEFAULT_PORT: u16 = 9000;
+    let value = if value.is_empty() || value == ":" {
+        format!("{DEFAULT_DOMAIN}:{DEFAULT_PORT}")
+    } else if value.starts_with(':') {
+        format!("{DEFAULT_DOMAIN}{value}")
+    } else if value.ends_with(':') {
+        format!("{value}{DEFAULT_PORT}")
+    } else if value.parse::<u16>().is_ok() {
+        format!("{DEFAULT_DOMAIN}:{value}")
+    } else if value.contains(':') {
+        value.to_string()
+    } else {
+        format!("{value}:{DEFAULT_PORT}")
+    };
+    match value.to_socket_addrs() {
+        Ok(mut iter) => iter.next().ok_or(eyre::Error::msg(format!("\"{value}\""))),
+        Err(e) => Err(eyre::Error::from(e).wrap_err(format!("\"{value}\""))),
+    }
+}
+
 /// Tracing utility
 pub mod reth_tracing {
     use tracing::Subscriber;
@@ -102,3 +126,19 @@ pub mod reth_tracing {
             .with(filter)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use std::net::ToSocketAddrs;
+
+    use super::socketaddr_value_parser;
+
+    #[test]
+    fn parse_socketaddr_with_default() {
+        let expected = "localhost:9000".to_socket_addrs().unwrap().next().unwrap();
+        let test_values = ["localhost:9000", ":9000", "9000", "localhost:", "localhost", ":", ""];
+        for value in test_values {
+            assert_eq!(socketaddr_value_parser(value).expect("value_parser failed"), expected);
+        }
+    }
+}