Merge branch 'develop' of https://github.com/prysmaticlabs/geth-sharding into debugE2EFailure

validator/client/BUILD.bazel

@@ -83,6 +83,7 @@ go_library(
         "@com_github_prometheus_client_golang//prometheus/promauto:go_default_library",
         "@com_github_prysmaticlabs_go_bitfield//:go_default_library",
         "@com_github_sirupsen_logrus//:go_default_library",
+        "@in_gopkg_d4l3k_messagediff_v1//:go_default_library",
         "@io_opencensus_go//plugin/ocgrpc:go_default_library",
         "@io_opencensus_go//trace:go_default_library",
         "@org_golang_google_grpc//:go_default_library",

validator/client/validator.go

@@ -49,6 +49,7 @@ import (
 	"google.golang.org/grpc/status"
 	"google.golang.org/protobuf/proto"
 	"google.golang.org/protobuf/types/known/emptypb"
+	"gopkg.in/d4l3k/messagediff.v1"
 )
 
 // keyFetchPeriod is the frequency that we try to refetch validating keys
@@ -588,6 +589,14 @@ func (v *validator) UpdateDuties(ctx context.Context, slot primitives.Slot) erro
 		log.WithError(err).Error("error getting validator duties")
 		return err
 	}
+	if diff, isEqual := messagediff.PrettyDiff(resp.Duties, resp.CurrentEpochDuties); !isEqual {
+		v.dutiesLock.Lock()
+		v.duties = nil // Clear assignments so we know to retry the request.
+		v.dutiesLock.Unlock()
+		wrappedErr := errors.Errorf("duties are different: %s", diff)
+		log.WithError(wrappedErr).Error("error getting validator duties")
+		return wrappedErr
+	}
 
 	v.dutiesLock.Lock()
 	v.duties = resp