feat(engine): extract engine validator to customize

Cargo.toml

@@ -63,6 +63,7 @@ base-jwt = { path = "crates/shared/jwt" }
 
 # Client
 base-client-cli = { path = "crates/client/cli" }
+base-client-engine = { path = "crates/client/engine" }
 base-client-node = { path = "crates/client/node" }
 base-metering = { path = "crates/client/metering" }
 base-txpool = { path = "crates/client/txpool" }

crates/client/engine/Cargo.toml

@@ -0,0 +1,50 @@
+[package]
+name = "base-client-engine"
+description = "Engine validator for Base Node"
+version.workspace = true
+edition.workspace = true
+rust-version.workspace = true
+license.workspace = true
+homepage.workspace = true
+repository.workspace = true
+
+[lints]
+workspace = true
+
+[dependencies]
+alloy-consensus.workspace = true
+alloy-eips.workspace = true
+alloy-evm.workspace = true
+alloy-primitives.workspace = true
+alloy-rpc-types.workspace = true
+alloy-rpc-types-engine.workspace = true
+jsonrpsee.workspace = true
+rayon.workspace = true
+reth-chain-state.workspace = true
+reth-chainspec.workspace = true
+reth-consensus.workspace = true
+reth-engine-primitives.workspace = true
+reth-engine-tree.workspace = true
+reth-errors.workspace = true
+reth-evm.workspace = true
+reth-node-api.workspace = true
+reth-node-builder.workspace = true
+reth-node-core.workspace = true
+reth-payload-builder.workspace = true
+reth-payload-primitives.workspace = true
+reth-primitives-traits.workspace = true
+reth-provider.workspace = true
+reth-revm.workspace = true
+reth-rpc.workspace = true
+reth-rpc-api.workspace = true
+reth-rpc-builder.workspace = true
+reth-rpc-engine-api.workspace = true
+reth-rpc-eth-types.workspace = true
+reth-tokio-util.workspace = true
+reth-tracing.workspace = true
+reth-trie.workspace = true
+reth-trie-parallel.workspace = true
+revm-primitives.workspace = true
+tracing.workspace = true
+eyre.workspace = true
+derive_more.workspace = true

crates/client/engine/README.md

@@ -0,0 +1,106 @@
+# `base-client-engine`
+
+<a href="https://github.com/base/node-reth/actions/workflows/ci.yml"><img src="https://github.com/base/node-reth/actions/workflows/ci.yml/badge.svg?label=ci" alt="CI"></a>
+<a href="https://github.com/base/node-reth/blob/main/LICENSE"><img src="https://img.shields.io/badge/License-MIT-d1d1f6.svg?label=license&labelColor=2a2f35" alt="MIT License"></a>
+
+Custom engine validator implementation optimized for validating canonical blocks in the Base node.
+
+## Overview
+
+This crate provides a specialized engine validator that integrates with Reth's engine tree and consensus system. It is optimized for validating canonical blocks after flashblock validation and serves as a building block for Base-specific consensus and execution logic.
+
+### Key Components
+
+- **`BaseEngineValidator`**: A wrapper around Reth's `BasicEngineValidator` that provides reusable payload validation logic. It handles:
+  - Consensus validation
+  - Block execution
+  - State root computation
+  - Fork detection
+
+- **`BaseEngineValidatorBuilder`**: A builder that constructs `BaseEngineValidator` instances with the necessary context (provider, consensus engine, EVM config, payload validator, and invalid block hooks).
+
+## Features
+
+- **Payload Validation**: Validates execution payloads from the Engine API against the current chain state
+- **Block Validation**: Validates pre-constructed blocks (e.g., from flashblocks) efficiently
+- **State Management**: Computes and verifies state roots during block execution
+- **Invalid Block Handling**: Integrates with Reth's invalid block hooks for debugging and analysis
+
+## Usage
+
+Add the dependency to your `Cargo.toml`:
+
+```toml
+[dependencies]
+base-client-engine = { git = "https://github.com/base/node-reth" }
+```
+
+### Using with Node Builder
+
+The validator builder integrates with Reth's node builder pattern:
+
+```rust,ignore
+use base_client_engine::BaseEngineValidatorBuilder;
+use reth_node_builder::NodeBuilder;
+
+// Create a validator builder with your custom payload validator
+let validator_builder = BaseEngineValidatorBuilder::new(my_payload_validator_builder);
+
+// The node builder will automatically use this to construct the engine validator
+let node = NodeBuilder::new()
+    .with_engine_validator_builder(validator_builder)
+    .build()
+    .await?;
+```
+
+### Custom Payload Validation
+
+Implement custom payload validation logic by providing your own `PayloadValidatorBuilder`:
+
+```rust,ignore
+use base_client_engine::BaseEngineValidatorBuilder;
+use reth_engine_primitives::PayloadValidator;
+use reth_node_builder::rpc::PayloadValidatorBuilder;
+
+#[derive(Debug, Clone)]
+struct MyPayloadValidatorBuilder;
+
+impl<Node> PayloadValidatorBuilder<Node> for MyPayloadValidatorBuilder
+where
+    Node: FullNodeComponents,
+{
+    type Validator = MyPayloadValidator;
+
+    async fn build(self, ctx: &AddOnsContext<'_, Node>) -> eyre::Result<Self::Validator> {
+        Ok(MyPayloadValidator::new(/* ... */))
+    }
+}
+
+// Use with the base engine validator builder
+let engine_validator_builder = BaseEngineValidatorBuilder::new(MyPayloadValidatorBuilder);
+```
+
+## Architecture
+
+The validator follows a layered architecture:
+
+1. **Builder Layer** (`BaseEngineValidatorBuilder`): Constructs validators with the necessary dependencies
+2. **Validation Layer** (`BaseEngineValidator`): Coordinates validation, execution, and state computation
+3. **Integration Layer**: Implements `EngineValidator` trait to work with Reth's engine tree
+
+This design allows for composable, network-specific validation logic while reusing common execution and state management code.
+
+## Dependencies
+
+This crate builds on top of several Reth components:
+- `reth-engine-tree`: Engine tree primitives and traits
+- `reth-consensus`: Consensus validation
+- `reth-evm`: EVM execution configuration
+- `reth-provider`: State and storage access
+- `reth-payload-primitives`: Payload types and validation
+
+## Related Crates
+
+- **`base-flashblocks`**: Provides optimized block building that works with this validator
+- **`base-client-node`**: Node builder extensions that integrate this validator
+- **`reth-engine-tree`**: Core engine tree implementation

crates/client/engine/src/lib.rs

@@ -0,0 +1,5 @@
+//! Implements custom engine validator that is optimized for validating canonical blocks
+//! after flashblock validation.
+
+pub mod validator;
+pub use validator::{BaseEngineValidator, BaseEngineValidatorBuilder};