diff --git a/internal/net/grpc/interceptor/server/metric/metric.go b/internal/net/grpc/interceptor/server/metric/metric.go
index c1c8edfccb..f77817cdae 100644
--- a/internal/net/grpc/interceptor/server/metric/metric.go
+++ b/internal/net/grpc/interceptor/server/metric/metric.go
@@ -55,17 +55,7 @@ func MetricInterceptors() (grpc.UnaryServerInterceptor, grpc.StreamServerInterce
 	}
 
 	record := func(ctx context.Context, method string, err error, latency float64) {
-		code := codes.OK // default error is success when error is nil
-		if err != nil {
-			st, _ := status.FromError(err)
-			if st != nil {
-				code = st.Code()
-			}
-		}
-		attrs := []attribute.KeyValue{
-			attribute.String(gRPCMethodKeyName, method),
-			attribute.String(gRPCStatus, code.String()),
-		}
+		attrs := attributesFromError(method, err)
 		latencyHistgram.Record(ctx, latency, attrs...)
 		completedRPCCnt.Add(ctx, 1, attrs...)
 	}
@@ -83,3 +73,17 @@ func MetricInterceptors() (grpc.UnaryServerInterceptor, grpc.StreamServerInterce
 			return err
 		}, nil
 }
+
+func attributesFromError(method string, err error) []attribute.KeyValue {
+	code := codes.OK // default error is success when error is nil
+	if err != nil {
+		st, _ := status.FromError(err)
+		if st != nil {
+			code = st.Code()
+		}
+	}
+	return []attribute.KeyValue{
+		attribute.String(gRPCMethodKeyName, method),
+		attribute.String(gRPCStatus, code.String()),
+	}
+}
diff --git a/internal/net/grpc/interceptor/server/metric/metric_test.go b/internal/net/grpc/interceptor/server/metric/metric_test.go
index f5538e439a..12f341d781 100644
--- a/internal/net/grpc/interceptor/server/metric/metric_test.go
+++ b/internal/net/grpc/interceptor/server/metric/metric_test.go
@@ -14,11 +14,15 @@
 package metric
 
 import (
+	"context"
 	"reflect"
 	"testing"
 
 	"github.com/vdaas/vald/internal/errors"
 	"github.com/vdaas/vald/internal/net/grpc"
+	"github.com/vdaas/vald/internal/net/grpc/codes"
+	"github.com/vdaas/vald/internal/net/grpc/status"
+	"github.com/vdaas/vald/internal/observability/attribute"
 	"github.com/vdaas/vald/internal/test/goleak"
 )
 
@@ -92,3 +96,95 @@ func TestMetricInterceptors(t *testing.T) {
 		})
 	}
 }
+
+func Test_attributesFromError(t *testing.T) {
+	type T = []attribute.KeyValue
+	type args struct {
+		method string
+		err    error
+	}
+	type want struct {
+		obj T
+	}
+	type test struct {
+		name       string
+		args       args
+		want       want
+		checkFunc  func(w want, obj T) error
+		beforeFunc func(*testing.T, args)
+		afterFunc  func(*testing.T, args)
+	}
+
+	defaultCheckFunc := func(w want, obj T) error {
+		if !reflect.DeepEqual(obj, w.obj) {
+			return errors.Errorf("got: \"%#v\",\n\t\t\t\twant: \"%#v\"", obj, w.obj)
+		}
+		return nil
+	}
+
+	tests := []test{
+		{
+			name: "return []attribute.KeyValue when err is nil",
+			args: args{
+				method: "InsertRPC",
+				err:    nil,
+			},
+			want: want{
+				obj: []attribute.KeyValue{
+					attribute.String(gRPCMethodKeyName, "InsertRPC"),
+					attribute.String(gRPCStatus, codes.OK.String()),
+				},
+			},
+		},
+		{
+			name: "return []attribute.KeyValue when err is not nil",
+			args: args{
+				method: "InsertRPC",
+				err:    context.DeadlineExceeded,
+			},
+			want: want{
+				obj: []attribute.KeyValue{
+					attribute.String(gRPCMethodKeyName, "InsertRPC"),
+					attribute.String(gRPCStatus, codes.DeadlineExceeded.String()),
+				},
+			},
+		},
+		{
+			name: "return []attribute.KeyValue when err type is wrapped error",
+			args: args{
+				method: "InsertRPC",
+				err:    status.WrapWithInvalidArgument("Insert API failed", errors.ErrIncompatibleDimensionSize(100, 940)),
+			},
+			want: want{
+				obj: []attribute.KeyValue{
+					attribute.String(gRPCMethodKeyName, "InsertRPC"),
+					attribute.String(gRPCStatus, codes.InvalidArgument.String()),
+				},
+			},
+		},
+	}
+
+	for _, tc := range tests {
+		test := tc
+		t.Run(test.name, func(tt *testing.T) {
+			tt.Parallel()
+			defer goleak.VerifyNone(tt, goleak.IgnoreCurrent())
+			if test.beforeFunc != nil {
+				test.beforeFunc(tt, test.args)
+			}
+			if test.afterFunc != nil {
+				defer test.afterFunc(tt, test.args)
+			}
+
+			checkFunc := test.checkFunc
+			if test.checkFunc == nil {
+				checkFunc = defaultCheckFunc
+			}
+
+			got := attributesFromError(test.args.method, test.args.err)
+			if err := checkFunc(test.want, got); err != nil {
+				tt.Errorf("error = %v", err)
+			}
+		})
+	}
+}