Refactor ClientConfig, add serde to it

beacon_node/rpc/src/config.rs

@@ -1,7 +1,9 @@
+use clap::ArgMatches;
+use serde_derive::{Deserialize, Serialize};
 use std::net::Ipv4Addr;
 
 /// RPC Configuration
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Config {
     /// Enable the RPC server.
     pub enabled: bool,
@@ -20,3 +22,23 @@ impl Default for Config {
         }
     }
 }
+
+impl Config {
+    pub fn apply_cli_args(&mut self, args: &ArgMatches) -> Result<(), &'static str> {
+        if args.is_present("rpc") {
+            self.enabled = true;
+        }
+
+        if let Some(rpc_address) = args.value_of("rpc-address") {
+            self.listen_address = rpc_address
+                .parse::<Ipv4Addr>()
+                .map_err(|_| "rpc-address is not IPv4 address")?;
+        }
+
+        if let Some(rpc_port) = args.value_of("rpc-port") {
+            self.port = rpc_port.parse::<u16>().map_err(|_| "rpc-port is not u16")?;
+        }
+
+        Ok(())
+    }
+}