feat: support customizable RPC namespace parsers

crates/ethereum/cli/Cargo.toml

@@ -21,6 +21,7 @@ reth-node-builder.workspace = true
 reth-node-core.workspace = true
 reth-node-ethereum.workspace = true
 reth-node-metrics.workspace = true
+reth-rpc-server-types.workspace = true
 reth-tracing.workspace = true
 reth-node-api.workspace = true
 

crates/ethereum/cli/src/interface.rs

@@ -18,24 +18,32 @@ use reth_node_builder::{NodeBuilder, WithLaunchContext};
 use reth_node_core::{args::LogArgs, version::version_metadata};
 use reth_node_ethereum::{consensus::EthBeaconConsensus, EthEvmConfig, EthereumNode};
 use reth_node_metrics::recorder::install_prometheus_recorder;
+use reth_rpc_server_types::{DefaultRpcModuleValidator, RpcModuleValidator};
 use reth_tracing::FileWorkerGuard;
-use std::{ffi::OsString, fmt, future::Future, sync::Arc};
+use std::{ffi::OsString, fmt, future::Future, marker::PhantomData, sync::Arc};
 use tracing::info;
 
 /// The main reth cli interface.
 ///
 /// This is the entrypoint to the executable.
 #[derive(Debug, Parser)]
 #[command(author, version =version_metadata().short_version.as_ref(), long_version = version_metadata().long_version.as_ref(), about = "Reth", long_about = None)]
-pub struct Cli<C: ChainSpecParser = EthereumChainSpecParser, Ext: clap::Args + fmt::Debug = NoArgs>
-{
+pub struct Cli<
+    C: ChainSpecParser = EthereumChainSpecParser,
+    Ext: clap::Args + fmt::Debug = NoArgs,
+    Rpc: RpcModuleValidator = DefaultRpcModuleValidator,
+> {
     /// The command to run
     #[command(subcommand)]
     pub command: Commands<C, Ext>,
 
     /// The logging configuration for the CLI.
     #[command(flatten)]
     pub logs: LogArgs,
+
+    /// Type marker for the RPC module validator
+    #[arg(skip)]
+    pub _phantom: PhantomData<Rpc>,
 }
 
 impl Cli {
@@ -54,7 +62,7 @@ impl Cli {
     }
 }
 
-impl<C: ChainSpecParser, Ext: clap::Args + fmt::Debug> Cli<C, Ext> {
+impl<C: ChainSpecParser, Ext: clap::Args + fmt::Debug, Rpc: RpcModuleValidator> Cli<C, Ext, Rpc> {
     /// Execute the configured cli command.
     ///
     /// This accepts a closure that is used to launch the node via the
@@ -190,9 +198,20 @@ impl<C: ChainSpecParser, Ext: clap::Args + fmt::Debug> Cli<C, Ext> {
         let _ = install_prometheus_recorder();
 
         match self.command {
-            Commands::Node(command) => runner.run_command_until_exit(|ctx| {
-                command.execute(ctx, FnLauncher::new::<C, Ext>(launcher))
-            }),
+            Commands::Node(command) => {
+                // Validate RPC modules using the configured validator
+                if let Some(http_api) = &command.rpc.http_api {
+                    Rpc::validate_selection(http_api, "http.api")
+                        .map_err(|e| eyre::eyre!("{e}"))?;
+                }
+                if let Some(ws_api) = &command.rpc.ws_api {
+                    Rpc::validate_selection(ws_api, "ws.api").map_err(|e| eyre::eyre!("{e}"))?;
+                }
+
+                runner.run_command_until_exit(|ctx| {
+                    command.execute(ctx, FnLauncher::new::<C, Ext>(launcher))
+                })
+            }
             Commands::Init(command) => runner.run_blocking_until_ctrl_c(command.execute::<N>()),
             Commands::InitState(command) => {
                 runner.run_blocking_until_ctrl_c(command.execute::<N>())
@@ -417,4 +436,72 @@ mod tests {
         .unwrap();
         assert!(reth.run(async move |_, _| Ok(())).is_ok());
     }
+
+    #[test]
+    fn test_rpc_module_validation() {
+        use reth_rpc_server_types::RethRpcModule;
+
+        // Test that standard modules are accepted
+        let cli =
+            Cli::try_parse_args_from(["reth", "node", "--http.api", "eth,admin,debug"]).unwrap();
+
+        if let Commands::Node(command) = &cli.command {
+            if let Some(http_api) = &command.rpc.http_api {
+                // Should contain the expected modules
+                let modules = http_api.to_selection();
+                assert!(modules.contains(&RethRpcModule::Eth));
+                assert!(modules.contains(&RethRpcModule::Admin));
+                assert!(modules.contains(&RethRpcModule::Debug));
+            } else {
+                panic!("Expected http.api to be set");
+            }
+        } else {
+            panic!("Expected Node command");
+        }
+
+        // Test that unknown modules are parsed as Other variant
+        let cli =
+            Cli::try_parse_args_from(["reth", "node", "--http.api", "eth,customrpc"]).unwrap();
+
+        if let Commands::Node(command) = &cli.command {
+            if let Some(http_api) = &command.rpc.http_api {
+                let modules = http_api.to_selection();
+                assert!(modules.contains(&RethRpcModule::Eth));
+                assert!(modules.contains(&RethRpcModule::Other("customrpc".to_string())));
+            } else {
+                panic!("Expected http.api to be set");
+            }
+        } else {
+            panic!("Expected Node command");
+        }
+    }
+
+    #[test]
+    fn test_rpc_module_unknown_rejected() {
+        use reth_cli_runner::CliRunner;
+
+        // Test that unknown module names are rejected during validation
+        let cli =
+            Cli::try_parse_args_from(["reth", "node", "--http.api", "unknownmodule"]).unwrap();
+
+        // When we try to run the CLI with validation, it should fail
+        let runner = CliRunner::try_default_runtime().unwrap();
+        let result = cli.with_runner(runner, |_, _| async { Ok(()) });
+
+        assert!(result.is_err());
+        let err = result.unwrap_err();
+        let err_msg = err.to_string();
+
+        // The error should mention it's an unknown module
+        assert!(
+            err_msg.contains("Unknown RPC module"),
+            "Error should mention unknown module: {}",
+            err_msg
+        );
+        assert!(
+            err_msg.contains("'unknownmodule'"),
+            "Error should mention the module name: {}",
+            err_msg
+        );
+    }
 }

crates/node/core/src/args/rpc_server.rs

@@ -380,7 +380,7 @@ impl Default for RpcServerArgs {
     }
 }
 
-/// clap value parser for [`RpcModuleSelection`].
+/// clap value parser for [`RpcModuleSelection`] with configurable validation.
 #[derive(Clone, Debug, Default)]
 #[non_exhaustive]
 struct RpcModuleSelectionValueParser;
@@ -391,23 +391,20 @@ impl TypedValueParser for RpcModuleSelectionValueParser {
     fn parse_ref(
         &self,
         _cmd: &Command,
-        arg: Option<&Arg>,
+        _arg: Option<&Arg>,
         value: &OsStr,
     ) -> Result<Self::Value, clap::Error> {
         let val =
             value.to_str().ok_or_else(|| clap::Error::new(clap::error::ErrorKind::InvalidUtf8))?;
-        val.parse::<RpcModuleSelection>().map_err(|err| {
-            let arg = arg.map(|a| a.to_string()).unwrap_or_else(|| "...".to_owned());
-            let possible_values = RethRpcModule::all_variant_names().to_vec().join(",");
-            let msg = format!(
-                "Invalid value '{val}' for {arg}: {err}.\n    [possible values: {possible_values}]"
-            );
-            clap::Error::raw(clap::error::ErrorKind::InvalidValue, msg)
-        })
+        // This will now accept any module name, creating Other(name) for unknowns
+        Ok(val
+            .parse::<RpcModuleSelection>()
+            .expect("RpcModuleSelection parsing cannot fail with Other variant"))
     }
 
     fn possible_values(&self) -> Option<Box<dyn Iterator<Item = PossibleValue> + '_>> {
-        let values = RethRpcModule::all_variant_names().iter().map(PossibleValue::new);
+        // Only show standard modules in help text (excludes "other")
+        let values = RethRpcModule::standard_variant_names().map(PossibleValue::new);
         Some(Box::new(values))
     }
 }

crates/optimism/cli/Cargo.toml

@@ -12,8 +12,10 @@ workspace = true
 
 [dependencies]
 reth-static-file-types = { workspace = true, features = ["clap"] }
+reth-cli.workspace = true
 reth-cli-commands.workspace = true
 reth-consensus.workspace = true
+reth-rpc-server-types.workspace = true
 reth-primitives-traits.workspace = true
 reth-db = { workspace = true, features = ["mdbx", "op"] }
 reth-db-api.workspace = true
@@ -39,7 +41,6 @@ reth-optimism-consensus.workspace = true
 reth-chainspec.workspace = true
 reth-node-events.workspace = true
 reth-optimism-evm.workspace = true
-reth-cli.workspace = true
 reth-cli-runner.workspace = true
 reth-node-builder = { workspace = true, features = ["op"] }
 reth-tracing.workspace = true

crates/optimism/cli/src/app.rs

@@ -7,25 +7,27 @@ use reth_node_metrics::recorder::install_prometheus_recorder;
 use reth_optimism_chainspec::OpChainSpec;
 use reth_optimism_consensus::OpBeaconConsensus;
 use reth_optimism_node::{OpExecutorProvider, OpNode};
+use reth_rpc_server_types::RpcModuleValidator;
 use reth_tracing::{FileWorkerGuard, Layers};
 use std::{fmt, sync::Arc};
 use tracing::info;
 
 /// A wrapper around a parsed CLI that handles command execution.
 #[derive(Debug)]
-pub struct CliApp<Spec: ChainSpecParser, Ext: clap::Args + fmt::Debug> {
-    cli: Cli<Spec, Ext>,
+pub struct CliApp<Spec: ChainSpecParser, Ext: clap::Args + fmt::Debug, Rpc: RpcModuleValidator> {
+    cli: Cli<Spec, Ext, Rpc>,
     runner: Option<CliRunner>,
     layers: Option<Layers>,
     guard: Option<FileWorkerGuard>,
 }
 
-impl<C, Ext> CliApp<C, Ext>
+impl<C, Ext, Rpc> CliApp<C, Ext, Rpc>
 where
     C: ChainSpecParser<ChainSpec = OpChainSpec>,
     Ext: clap::Args + fmt::Debug,
+    Rpc: RpcModuleValidator,
 {
-    pub(crate) fn new(cli: Cli<C, Ext>) -> Self {
+    pub(crate) fn new(cli: Cli<C, Ext, Rpc>) -> Self {
         Self { cli, runner: None, layers: Some(Layers::new()), guard: None }
     }
 
@@ -71,6 +73,14 @@ where
 
         match self.cli.command {
             Commands::Node(command) => {
+                // Validate RPC modules using the configured validator
+                if let Some(http_api) = &command.rpc.http_api {
+                    Rpc::validate_selection(http_api, "http.api").map_err(|e| eyre!("{e}"))?;
+                }
+                if let Some(ws_api) = &command.rpc.ws_api {
+                    Rpc::validate_selection(ws_api, "ws.api").map_err(|e| eyre!("{e}"))?;
+                }
+
                 runner.run_command_until_exit(|ctx| command.execute(ctx, launcher))
             }
             Commands::Init(command) => {

crates/optimism/cli/src/lib.rs

@@ -35,8 +35,9 @@ pub mod ovm_file_codec;
 pub use app::CliApp;
 pub use commands::{import::ImportOpCommand, import_receipts::ImportReceiptsOpCommand};
 use reth_optimism_chainspec::OpChainSpec;
+use reth_rpc_server_types::{DefaultRpcModuleValidator, RpcModuleValidator};
 
-use std::{ffi::OsString, fmt, sync::Arc};
+use std::{ffi::OsString, fmt, marker::PhantomData, sync::Arc};
 
 use chainspec::OpChainSpecParser;
 use clap::{command, Parser};
@@ -59,15 +60,22 @@ use reth_node_metrics as _;
 /// This is the entrypoint to the executable.
 #[derive(Debug, Parser)]
 #[command(author, version = version_metadata().short_version.as_ref(), long_version = version_metadata().long_version.as_ref(), about = "Reth", long_about = None)]
-pub struct Cli<Spec: ChainSpecParser = OpChainSpecParser, Ext: clap::Args + fmt::Debug = RollupArgs>
-{
+pub struct Cli<
+    Spec: ChainSpecParser = OpChainSpecParser,
+    Ext: clap::Args + fmt::Debug = RollupArgs,
+    Rpc: RpcModuleValidator = DefaultRpcModuleValidator,
+> {
     /// The command to run
     #[command(subcommand)]
     pub command: Commands<Spec, Ext>,
 
     /// The logging configuration for the CLI.
     #[command(flatten)]
     pub logs: LogArgs,
+
+    /// Type marker for the RPC module validator
+    #[arg(skip)]
+    _phantom: PhantomData<Rpc>,
 }
 
 impl Cli {
@@ -86,16 +94,17 @@ impl Cli {
     }
 }
 
-impl<C, Ext> Cli<C, Ext>
+impl<C, Ext, Rpc> Cli<C, Ext, Rpc>
 where
     C: ChainSpecParser<ChainSpec = OpChainSpec>,
     Ext: clap::Args + fmt::Debug,
+    Rpc: RpcModuleValidator,
 {
     /// Configures the CLI and returns a [`CliApp`] instance.
     ///
     /// This method is used to prepare the CLI for execution by wrapping it in a
     /// [`CliApp`] that can be further configured before running.
-    pub fn configure(self) -> CliApp<C, Ext> {
+    pub fn configure(self) -> CliApp<C, Ext, Rpc> {
         CliApp::new(self)
     }
 

crates/optimism/reth/src/lib.rs

@@ -24,7 +24,11 @@ pub mod primitives {
 #[cfg(feature = "cli")]
 pub mod cli {
     #[doc(inline)]
-    pub use reth_cli_util::*;
+    pub use reth_cli_util::{
+        allocator, get_secret_key, hash_or_num_value_parser, load_secret_key,
+        parse_duration_from_secs, parse_duration_from_secs_or_ms, parse_ether_value,
+        parse_socket_address, sigsegv_handler,
+    };
     #[doc(inline)]
     pub use reth_optimism_cli::*;
 }

crates/rpc/rpc-builder/src/lib.rs

@@ -915,11 +915,10 @@ where
         let namespaces: Vec<_> = namespaces.collect();
         namespaces
             .iter()
-            .copied()
             .map(|namespace| {
                 self.modules
-                    .entry(namespace)
-                    .or_insert_with(|| match namespace {
+                    .entry(namespace.clone())
+                    .or_insert_with(|| match namespace.clone() {
                         RethRpcModule::Admin => {
                             AdminApi::new(self.network.clone(), self.provider.chain_spec())
                                 .into_rpc()
@@ -981,7 +980,9 @@ where
                         // only relevant for Ethereum and configured in `EthereumAddOns`
                         // implementation
                         // TODO: can we get rid of this here?
-                        RethRpcModule::Flashbots => Default::default(),
+                        // Custom modules are not handled here - they should be registered via
+                        // extend_rpc_modules
+                        RethRpcModule::Flashbots | RethRpcModule::Other(_) => Default::default(),
                         RethRpcModule::Miner => MinerApi::default().into_rpc().into(),
                         RethRpcModule::Mev => {
                             EthSimBundle::new(eth_api.clone(), self.blocking_pool_guard.clone())
@@ -1570,9 +1571,9 @@ impl TransportRpcModuleConfig {
             let ws_modules =
                 self.ws.as_ref().map(RpcModuleSelection::to_selection).unwrap_or_default();
 
-            let http_not_ws = http_modules.difference(&ws_modules).copied().collect();
-            let ws_not_http = ws_modules.difference(&http_modules).copied().collect();
-            let overlap = http_modules.intersection(&ws_modules).copied().collect();
+            let http_not_ws = http_modules.difference(&ws_modules).cloned().collect();
+            let ws_not_http = ws_modules.difference(&http_modules).cloned().collect();
+            let overlap = http_modules.intersection(&ws_modules).cloned().collect();
 
             Err(WsHttpSamePortError::ConflictingModules(Box::new(ConflictingModules {
                 overlap,
@@ -1708,7 +1709,7 @@ impl TransportRpcModules {
     /// Returns all unique endpoints installed for the given module.
     ///
     /// Note: In case of duplicate method names this only record the first occurrence.
-    pub fn methods_by_module<F>(&self, module: RethRpcModule) -> Methods {
+    pub fn methods_by_module(&self, module: RethRpcModule) -> Methods {
         self.methods_by(|name| name.starts_with(module.as_str()))
     }
 

crates/rpc/rpc-server-types/src/lib.rs

@@ -13,6 +13,9 @@ pub mod constants;
 pub mod result;
 
 mod module;
-pub use module::{RethRpcModule, RpcModuleSelection};
+pub use module::{
+    DefaultRpcModuleValidator, LenientRpcModuleValidator, RethRpcModule, RpcModuleSelection,
+    RpcModuleValidator,
+};
 
 pub use result::ToRpcResult;