intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 59 insertions, 0 deletions

diff --git a/library/cpp/logger/backend_creator.h b/library/cpp/logger/backend_creator.h
new file mode 100644
index 0000000000..4f0ca24a4e
--- /dev/null
+++ b/library/cpp/logger/backend_creator.h
@@ -0,0 +1,59 @@
+#pragma once
+
+#include "backend.h"
+#include <library/cpp/object_factory/object_factory.h>
+#include <library/cpp/json/json_value.h>
+#include <util/generic/vector.h>
+#include <util/generic/ptr.h>
+#include <util/string/cast.h>
+
+class ILogBackendCreator {
+public:
+    using TFactory = NObjectFactory::TObjectFactory<ILogBackendCreator, TString>;
+
+    class IInitContext {
+    public:
+        template<class T>
+        bool GetValue(TStringBuf name, T& var) const {
+            TString tmp;
+            if (!GetValue(name, tmp)) {
+                return false;
+            }
+            var = FromString<T>(tmp);
+            return true;
+        }
+
+        template<class T>
+        T GetOrElse(TStringBuf name, const T& def) const {
+            T res;
+            return GetValue(name, res) ? res : def;
+        }
+
+        virtual ~IInitContext() = default;
+        virtual bool GetValue(TStringBuf name, TString& var) const = 0;
+        virtual TVector<THolder<IInitContext>> GetChildren(TStringBuf name) const = 0;
+    };
+
+public:
+    virtual ~ILogBackendCreator() = default;
+    THolder<TLogBackend> CreateLogBackend() const;
+    virtual bool Init(const IInitContext& ctx);
+
+    NJson::TJsonValue AsJson() const;
+    virtual void ToJson(NJson::TJsonValue& value) const = 0;
+
+    static THolder<ILogBackendCreator> Create(const IInitContext& ctx);
+
+private:
+    virtual THolder<TLogBackend> DoCreateLogBackend() const = 0;
+};
+
+class TLogBackendCreatorBase: public ILogBackendCreator {
+public:
+    TLogBackendCreatorBase(const TString& type);
+    virtual void ToJson(NJson::TJsonValue& value) const override final;
+
+protected:
+    virtual void DoToJson(NJson::TJsonValue& value) const = 0;
+    TString Type;
+};