intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 76 insertions, 0 deletions

diff --git a/library/cpp/monlib/deprecated/json/writer.h b/library/cpp/monlib/deprecated/json/writer.h
new file mode 100644
index 0000000000..183288143c
--- /dev/null
+++ b/library/cpp/monlib/deprecated/json/writer.h
@@ -0,0 +1,76 @@
+#pragma once
+
+#include <library/cpp/json/json_writer.h>
+
+namespace NMonitoring {
+    /**
+     * Deprecated writer of Solomon JSON format
+     * https://wiki.yandex-team.ru/solomon/api/dataformat/json
+     *
+     * This writer will be deleted soon, so please consider to use
+     * high level library library/cpp/monlib/encode which is decoupled from the
+     * particular format.
+     */
+    class TDeprecatedJsonWriter {
+    private:
+        NJson::TJsonWriter JsonWriter;
+        enum EState {
+            STATE_ROOT,
+            STATE_DOCUMENT,
+            STATE_COMMON_LABELS,
+            STATE_METRICS,
+            STATE_METRIC,
+            STATE_LABELS,
+        };
+        EState State;
+
+    public:
+        explicit TDeprecatedJsonWriter(IOutputStream* out);
+
+        void OpenDocument();
+        void CloseDocument();
+
+        void OpenCommonLabels();
+        void CloseCommonLabels();
+
+        void WriteCommonLabel(TStringBuf name, TStringBuf value);
+
+        void OpenMetrics();
+        void CloseMetrics();
+
+        void OpenMetric();
+        void CloseMetric();
+
+        void OpenLabels();
+        void CloseLabels();
+
+        void WriteLabel(TStringBuf name, TStringBuf value);
+
+        template <typename... T>
+        void WriteLabels(T... pairs) {
+            OpenLabels();
+            WriteLabelsInner(pairs...);
+            CloseLabels();
+        }
+
+        void WriteModeDeriv();
+
+        void WriteValue(long long value);
+        void WriteDoubleValue(double d);
+
+        void WriteTs(ui64 ts);
+
+    private:
+        void WriteLabelsInner(TStringBuf name, TStringBuf value) {
+            WriteLabel(name, value);
+        }
+
+        template <typename... T>
+        void WriteLabelsInner(TStringBuf name, TStringBuf value, T... pairs) {
+            WriteLabel(name, value);
+            WriteLabelsInner(pairs...);
+        }
+
+        inline void TransitionState(EState current, EState next);
+    };
+}