fix(taiko-client): fix path parsing in /eth/v1/config/spec (#18295)

packages/taiko-client/pkg/rpc/beaconclient.go

@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"github.com/ethereum/go-ethereum/log"
+	"github.com/pkg/errors"
 	"github.com/prysmaticlabs/prysm/v5/api/client"
 	"github.com/prysmaticlabs/prysm/v5/api/client/beacon"
 	"github.com/prysmaticlabs/prysm/v5/api/server/structs"
@@ -18,6 +19,7 @@ var (
 	// Request urls.
 	sidecarsRequestURL = "/eth/v1/beacon/blob_sidecars/%d"
 	genesisRequestURL  = "/eth/v1/beacon/genesis"
+	getConfigSpecPath  = "/eth/v1/config/spec"
 )
 
 type ConfigSpec struct {
@@ -67,7 +69,7 @@ func NewBeaconClient(endpoint string, timeout time.Duration) (*BeaconClient, err
 	log.Info("L1 genesis time", "time", genesisTime)
 
 	// Get the seconds per slot.
-	spec, err := cli.GetConfigSpec(ctx)
+	spec, err := getConfigSpec(ctx, cli)
 	if err != nil {
 		return nil, err
 	}
@@ -111,3 +113,17 @@ func (c *BeaconClient) timeToSlot(timestamp uint64) (uint64, error) {
 	}
 	return (timestamp - c.genesisTime) / c.secondsPerSlot, nil
 }
+
+// getConfigSpec retrieve the current configs of the network used by the beacon node.
+func getConfigSpec(ctx context.Context, c *beacon.Client) (*structs.GetSpecResponse, error) {
+	body, err := c.Get(ctx, c.BaseURL().Path+getConfigSpecPath)
+	if err != nil {
+		return nil, errors.Wrap(err, "error requesting configSpecPath")
+	}
+	fsr := &structs.GetSpecResponse{}
+	err = json.Unmarshal(body, fsr)
+	if err != nil {
+		return nil, err
+	}
+	return fsr, nil
+}