feat(l2-withdrawals): Define OpEngineApiBuilder (#14426)

crates/optimism/node/src/rpc.rs

@@ -0,0 +1,40 @@
+//! RPC component builder
+
+pub use reth_optimism_rpc::OpEngineApi;
+
+use reth_chainspec::EthereumHardforks;
+use reth_node_api::{
+    AddOnsContext, EngineTypes, ExecutionData, FullNodeComponents, NodeTypes, NodeTypesWithEngine,
+};
+use reth_node_builder::rpc::{BasicEngineApiBuilder, EngineApiBuilder, EngineValidatorBuilder};
+
+/// Builder for basic [`OpEngineApi`] implementation.
+#[derive(Debug, Default)]
+pub struct OpEngineApiBuilder<EV> {
+    inner: BasicEngineApiBuilder<EV>,
+}
+
+impl<N, EV> EngineApiBuilder<N> for OpEngineApiBuilder<EV>
+where
+    N: FullNodeComponents<
+        Types: NodeTypesWithEngine<
+            ChainSpec: EthereumHardforks,
+            Engine: EngineTypes<ExecutionData = ExecutionData>,
+        >,
+    >,
+    EV: EngineValidatorBuilder<N>,
+{
+    type EngineApi = OpEngineApi<
+        N::Provider,
+        <N::Types as NodeTypesWithEngine>::Engine,
+        N::Pool,
+        EV::Validator,
+        <N::Types as NodeTypes>::ChainSpec,
+    >;
+
+    async fn build_engine_api(self, ctx: &AddOnsContext<'_, N>) -> eyre::Result<Self::EngineApi> {
+        let inner = self.inner.build_engine_api(ctx).await?;
+
+        Ok(OpEngineApi::new(inner))
+    }
+}