json_helpers.hpp

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#pragma once
 
/// @file userver/dump/json_helpers.hpp
/// @brief Convenience functions to load and dump as JSON in classes derived
/// from components::CachingComponentBase.
 
#include <memory>
#include <string>
#include <string_view>
 
#include <userver/dump/common.hpp>
#include <userver/dump/operations.hpp>
#include <userver/dump/unsafe.hpp>
#include <userver/formats/json/serialize.hpp>
#include <userver/formats/json/string_builder.hpp>
#include <userver/formats/json/value.hpp>
 
USERVER_NAMESPACE_BEGIN
 
namespace dump {
 
/// @brief Convenience function to use in
/// components::CachingComponentBase::WriteContents override to dump a type in
/// a human readable JSON format.
///
/// @see @ref scripts/docs/en/userver/cache_dumps.md
template <typename T>
void WriteJson(Writer& writer, const T& contents) {
  formats::json::StringBuilder sb;
  WriteToStream(contents, sb);
  WriteStringViewUnsafe(writer, sb.GetString());
  WriteStringViewUnsafe(writer, "\n");
}
 
/// @brief Convenience function to use in
/// components::CachingComponentBase::ReadContents override to load a dump in
/// a human readable JSON format.
///
/// @see @ref scripts/docs/en/userver/cache_dumps.md
template <typename T>
std::unique_ptr<const T> ReadJson(Reader& reader) {
  return std::make_unique<const T>(
      formats::json::FromString(ReadEntire(reader)).As<T>());
}
 
}  // namespace dump
 
USERVER_NAMESPACE_END