intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 33 insertions, 0 deletions

diff --git a/library/cpp/protobuf/util/walk.h b/library/cpp/protobuf/util/walk.h
new file mode 100644
index 0000000000..d15d76562d
--- /dev/null
+++ b/library/cpp/protobuf/util/walk.h
@@ -0,0 +1,33 @@
+#pragma once
+
+#include "simple_reflection.h"
+
+#include <google/protobuf/message.h>
+#include <google/protobuf/descriptor.h>
+
+#include <functional>
+
+namespace NProtoBuf {
+    // Apply @onField processor to each field in @msg (even empty)
+    // Do not walk deeper the field if the field is an empty message
+    // Returned bool defines if we should walk down deeper to current node children (true), or not (false)
+    void WalkReflection(Message& msg,
+                        std::function<bool(Message&, const FieldDescriptor*)> onField);
+    void WalkReflection(const Message& msg,
+                        std::function<bool(const Message&, const FieldDescriptor*)> onField);
+
+    template <typename TOnField>
+    inline void WalkReflection(Message& msg, TOnField& onField) { // is used when TOnField is a callable class instance
+        WalkReflection(msg, std::function<bool(Message&, const FieldDescriptor*)>(std::ref(onField)));
+    }
+    template <typename TOnField>
+    inline void WalkReflection(const Message& msg, TOnField& onField) {
+        WalkReflection(msg, std::function<bool(const Message&, const FieldDescriptor*)>(std::ref(onField)));
+    }
+
+    // Apply @onField processor to each descriptor of a field
+    // Walk every field including nested messages. Avoid cyclic fields pointing to themselves
+    // Returned bool defines if we should walk down deeper to current node children (true), or not (false)
+    void WalkSchema(const Descriptor* descriptor, 
+                    std::function<bool(const FieldDescriptor*)> onField);
+}