Created Function to Reduce Duplicated Code

Cargo.lock

@@ -730,6 +730,10 @@ dependencies = [
  "eth2_ssz",
  "ethereum-types 0.12.1",
  "hex",
+ "serde",
+ "serde_json",
+ "serde_yaml",
+ "types",
 ]
 
 [[package]]

boot_node/src/lib.rs

@@ -3,8 +3,6 @@ use clap::ArgMatches;
 use slog::{o, Drain, Level, Logger};
 
 use eth2_network_config::Eth2NetworkConfig;
-use std::fs::File;
-use std::path::PathBuf;
 mod cli;
 pub mod config;
 mod server;
@@ -86,24 +84,13 @@ fn main<T: EthSpec>(
     // parse the CLI args into a useable config
     let config: BootNodeConfig<T> = BootNodeConfig::new(bn_matches, eth2_network_config)?;
 
-    // Dump config if `dump-config` flag is set
+    // Dump configs if `dump-config` or `dump-chain-config` flags are set
-    let dump_config = clap_utils::parse_optional::<PathBuf>(lh_matches, "dump-config")?;
+    let config_sz = BootNodeConfigSerialization::from_config_ref(&config);
-    if let Some(dump_path) = dump_config {
+    clap_utils::check_dump_configs::<_, T>(
-        let config_sz = BootNodeConfigSerialization::from_config_ref(&config);
+        lh_matches,
-        let mut file = File::create(dump_path)
+        &config_sz,
-            .map_err(|e| format!("Failed to create dumped config: {:?}", e))?;
+        &eth2_network_config.chain_spec::<T>()?,
-        serde_json::to_writer(&mut file, &config_sz)
+    )?;
-            .map_err(|e| format!("Error serializing config: {:?}", e))?;
-    }
-    if let Some(dump_path) = clap_utils::parse_optional::<PathBuf>(lh_matches, "dump-chain-config")?
-    {
-        let chain_config =
-            types::Config::from_chain_spec::<T>(&eth2_network_config.chain_spec::<T>()?);
-        let mut file = File::create(dump_path)
-            .map_err(|e| format!("Failed to create dumped chain config: {:?}", e))?;
-        serde_yaml::to_writer(&mut file, &chain_config)
-            .map_err(|e| format!("Error serializing chain config: {:?}", e))?;
-    }
 
     // Run the boot node
     if !lh_matches.is_present("immediate-shutdown") {

common/clap_utils/Cargo.toml

@@ -13,3 +13,7 @@ dirs = "3.0.1"
 eth2_network_config = { path = "../eth2_network_config" }
 eth2_ssz = "0.4.1"
 ethereum-types = "0.12.1"
+serde = "1.0.116"
+serde_json = "1.0.59"
+serde_yaml = "0.8.13"
+types = { path = "../../consensus/types"}

common/clap_utils/src/lib.rs

@@ -6,6 +6,7 @@ use ethereum_types::U256 as Uint256;
 use ssz::Decode;
 use std::path::PathBuf;
 use std::str::FromStr;
+use types::{ChainSpec, Config, EthSpec};
 
 pub mod flags;
 
@@ -163,3 +164,29 @@ pub fn parse_ssz_optional<T: Decode>(
         })
         .transpose()
 }
+
+/// Writes configs to file if `dump-config` or `dump-chain-config` flags are set
+pub fn check_dump_configs<S, E>(
+    matches: &ArgMatches,
+    config: S,
+    spec: &ChainSpec,
+) -> Result<(), String>
+where
+    S: serde::Serialize,
+    E: EthSpec,
+{
+    if let Some(dump_path) = parse_optional::<PathBuf>(matches, "dump-config")? {
+        let mut file = std::fs::File::create(dump_path)
+            .map_err(|e| format!("Failed to open file for writing config: {:?}", e))?;
+        serde_json::to_writer(&mut file, &config)
+            .map_err(|e| format!("Error serializing config: {:?}", e))?;
+    }
+    if let Some(dump_path) = parse_optional::<PathBuf>(matches, "dump-chain-config")? {
+        let chain_config = Config::from_chain_spec::<E>(spec);
+        let mut file = std::fs::File::create(dump_path)
+            .map_err(|e| format!("Failed to open file for writing chain config: {:?}", e))?;
+        serde_yaml::to_writer(&mut file, &chain_config)
+            .map_err(|e| format!("Error serializing config: {:?}", e))?;
+    }
+    Ok(())
+}

lighthouse/src/main.rs

@@ -13,11 +13,10 @@ use eth2_network_config::{Eth2NetworkConfig, DEFAULT_HARDCODED_NETWORK, HARDCODE
 use lighthouse_version::VERSION;
 use malloc_utils::configure_memory_allocator;
 use slog::{crit, info, warn};
-use std::fs::File;
 use std::path::PathBuf;
 use std::process::exit;
 use task_executor::ShutdownReason;
-use types::{Config, EthSpec, EthSpecId};
+use types::{EthSpec, EthSpecId};
 use validator_client::ProductionValidatorClient;
 
 fn bls_library_name() -> &'static str {
@@ -495,23 +494,8 @@ fn run<E: EthSpec>(
             let executor = context.executor.clone();
             let config = beacon_node::get_config::<E>(matches, &context)?;
             let shutdown_flag = matches.is_present("immediate-shutdown");
-            if let Some(dump_path) = clap_utils::parse_optional::<PathBuf>(matches, "dump-config")?
+            // Dump configs if `dump-config` or `dump-chain-config` flags are set
-            {
+            clap_utils::check_dump_configs::<_, E>(matches, &config, &context.eth2_config.spec)?;
-                let mut file = File::create(dump_path)
-                    .map_err(|e| format!("Failed to create dumped config: {:?}", e))?;
-                serde_json::to_writer(&mut file, &config)
-                    .map_err(|e| format!("Error serializing config: {:?}", e))?;
-            };
-            if let Some(dump_path) =
-                clap_utils::parse_optional::<PathBuf>(matches, "dump-chain-config")?
-            {
-                let chain_config = Config::from_chain_spec::<E>(&context.eth2_config.spec);
-                let mut file = File::create(dump_path)
-                    .map_err(|e| format!("Failed to create dumped chain config: {:?}", e))?;
-                serde_yaml::to_writer(&mut file, &chain_config)
-                    .map_err(|e| format!("Error serializing chain config: {:?}", e))?;
-            };
-
             executor.clone().spawn(
                 async move {
                     if let Err(e) = ProductionBeaconNode::new(context.clone(), config).await {
@@ -537,22 +521,8 @@ fn run<E: EthSpec>(
             let config = validator_client::Config::from_cli(matches, context.log())
                 .map_err(|e| format!("Unable to initialize validator config: {}", e))?;
             let shutdown_flag = matches.is_present("immediate-shutdown");
-            if let Some(dump_path) = clap_utils::parse_optional::<PathBuf>(matches, "dump-config")?
+            // Dump configs if `dump-config` or `dump-chain-config` flags are set
-            {
+            clap_utils::check_dump_configs::<_, E>(matches, &config, &context.eth2_config.spec)?;
-                let mut file = File::create(dump_path)
-                    .map_err(|e| format!("Failed to create dumped config: {:?}", e))?;
-                serde_json::to_writer(&mut file, &config)
-                    .map_err(|e| format!("Error serializing config: {:?}", e))?;
-            };
-            if let Some(dump_path) =
-                clap_utils::parse_optional::<PathBuf>(matches, "dump-chain-config")?
-            {
-                let chain_config = Config::from_chain_spec::<E>(&context.eth2_config.spec);
-                let mut file = File::create(dump_path)
-                    .map_err(|e| format!("Failed to create dumped chain config: {:?}", e))?;
-                serde_yaml::to_writer(&mut file, &chain_config)
-                    .map_err(|e| format!("Error serializing chain config: {:?}", e))?;
-            };
             if !shutdown_flag {
                 executor.clone().spawn(
                     async move {