SSZ-REST Engine API transport (EL server)

cmd/rpcdaemon/cli/config.go

@@ -960,6 +960,13 @@ func createHandler(cfg *httpcfg.HttpCfg, apiList []rpc.API, httpHandler http.Han
 			return
 		}
 
+		// EIP-8161: Route /engine/* paths to SSZ-REST handler,
+		// everything else (/) to JSON-RPC handler.
+		if cfg.SszRestHandler != nil && strings.HasPrefix(r.URL.Path, "/engine/") {
+			cfg.SszRestHandler.ServeHTTP(w, r)
+			return
+		}
+
 		httpHandler.ServeHTTP(w, r)
 	})
 

cmd/rpcdaemon/cli/httpcfg/http_cfg.go

@@ -17,6 +17,7 @@
 package httpcfg
 
 import (
+	"net/http"
 	"time"
 
 	"github.com/erigontech/erigon/db/datadir"
@@ -114,4 +115,8 @@ type HttpCfg struct {
 
 	RpcTxSyncDefaultTimeout time.Duration // Default timeout for eth_sendRawTransactionSync
 	RpcTxSyncMaxTimeout     time.Duration // Maximum timeout for eth_sendRawTransactionSync
+
+	// EIP-8161: SSZ-REST Engine API Transport — handler injected by EngineServer,
+	// served on the same port as JSON-RPC (path-based routing).
+	SszRestHandler http.Handler
 }

execution/engineapi/engine_server.go

@@ -92,6 +92,7 @@ type EngineServer struct {
 	// TODO Remove this on next release
 	printPectraBanner bool
 	maxReorgDepth     uint64
+	httpConfig        *httpcfg.HttpCfg
 }
 
 func NewEngineServer(
@@ -151,6 +152,7 @@ func (e *EngineServer) Start(
 			return nil
 		})
 	}
+	e.httpConfig = httpConfig
 	base := jsonrpc.NewBaseApi(filters, stateCache, blockReader, httpConfig.WithDatadir, httpConfig.EvmCallTimeout, engineReader, httpConfig.Dirs, nil, httpConfig.BlockRangeLimit, httpConfig.GetLogsMaxResults)
 	ethImpl := jsonrpc.NewEthAPI(base, db, eth, e.txpool, mining, jsonrpc.NewEthApiConfig(httpConfig), e.logger)
 
@@ -167,6 +169,11 @@ func (e *EngineServer) Start(
 			Version:   "1.0",
 		}}
 
+	// EIP-8161: Register SSZ-REST handler on the same port as JSON-RPC.
+	// Path-based routing: /engine/* → SSZ-REST, / → JSON-RPC
+	httpConfig.SszRestHandler = NewSszRestHandler(e, e.logger)
+	e.logger.Info("[EngineServer] SSZ-REST routes registered on Engine API port")
+
 	eg.Go(func() error {
 		defer e.logger.Debug("[EngineServer] engine rpc server goroutine terminated")
 		err := cli.StartRpcServerWithJwtAuthentication(ctx, httpConfig, apiList, e.logger)
@@ -175,6 +182,7 @@ func (e *EngineServer) Start(
 		}
 		return err
 	})
+
 	return eg.Wait()
 }