[ugc] Deserialization + combining with serialization. And review fixes

20 files changed, 208 insertions, 177 deletions

diff --git a/3party/jansson/myjansson.cpp b/3party/jansson/myjansson.cpp
index 34fd6ac1f7..ed59a2c7a0 100644
--- a/3party/jansson/myjansson.cpp
+++ b/3party/jansson/myjansson.cpp
@@ -38,11 +38,6 @@ void FromJSON(json_t * root, bool & result)
   result = json_is_true(root);
 }
 
-bool CheckJsonArray(json_t const * data)
-{
-  return data != nullptr && json_is_array(data) && json_array_size(data) > 0;
-}
-
 namespace std
 {
 void FromJSON(json_t * root, string & result)
diff --git a/3party/jansson/myjansson.hpp b/3party/jansson/myjansson.hpp
index 610ef8e870..5a6c438d34 100644
--- a/3party/jansson/myjansson.hpp
+++ b/3party/jansson/myjansson.hpp
@@ -171,8 +171,6 @@ void FromJSONObjectOptionalField(json_t * root, std::string const & field, std::
     FromJSON(json_array_get(arr, i), result[i]);
 }
 
-bool CheckJsonArray(json_t const * data);
-
 struct JSONFreeDeleter
 {
   void operator()(char * buffer) const { free(buffer); }
diff --git a/generator/gen_mwm_info.hpp b/generator/gen_mwm_info.hpp
index db3941b61e..de72c00cc0 100644
--- a/generator/gen_mwm_info.hpp
+++ b/generator/gen_mwm_info.hpp
@@ -74,7 +74,7 @@ public:
     try
     {
       FileReader reader(filename);
-      ReaderSource<FileReader> src(reader);
+      NonOwningReaderSource src(reader);
       Read(src);
     }
     catch (FileReader::Exception const & e)
diff --git a/generator/generator_tests/ugc_test.cpp b/generator/generator_tests/ugc_test.cpp
index 44ca9055b9..9f7df6fde4 100644
--- a/generator/generator_tests/ugc_test.cpp
+++ b/generator/generator_tests/ugc_test.cpp
@@ -6,12 +6,14 @@
 
 #include "ugc/types.hpp"
 
+#include "base/math.hpp"
+
 std::string g_database(R"LLL(
                        PRAGMA foreign_keys=OFF;
                        BEGIN TRANSACTION;
                        CREATE TABLE ratings (key bigint, value blob);
                        INSERT INTO "ratings" VALUES(9826352,'{"osm_id":9826352,"total_rating":10.34,"votes":721,"ratings":[{"id":2,"value":3.4},{"id":2,"value":6.0001}],"reviews":[{"id":7864532,"text":"The best service on the Earth","lang":"en","author":"Robert","rating":8.5,"date":1234567}]}');
-                       INSERT INTO "ratings" VALUES(9826353,'{"osm_id":9826353,"total_rating":0.34,"votes":1,"ratings":[{"id":2,"value":3.4},{"id":3,"value":6.0001},{"id":6,"value":0.0001}],"reviews":[{"id":78645323924,"text":"Заебись!","lang":"ru","author":"Вася","rating":10,"date":1234569}]}');
+                       INSERT INTO "ratings" VALUES(9826353,'{"osm_id":9826353,"total_rating":0.34,"votes":1,"ratings":[{"id":2,"value":3.4},{"id":3,"value":6.0001},{"id":6,"value":0.0001}],"reviews":[{"id":78645323924,"text":"Изумительно!","lang":"ru","author":"Вася","rating":10,"date":1234569}]}');
                        CREATE INDEX key_index ON ratings (key);
                        COMMIT;
 )LLL");
@@ -41,5 +43,5 @@ UNIT_TEST(UGC_TranslateRatingTest)
 
   TEST_EQUAL(ugc.m_ratings.size(), 2, ());
   TEST_EQUAL(ugc.m_ratings[0].m_key, "2", ());
-  TEST_LESS(ugc.m_ratings[0].m_value - 3.4, 1e-6, ());
+  TEST(my::AlmostEqualAbs(ugc.m_ratings[0].m_value, 3.4f, 1e-6f), ());
 }
diff --git a/generator/ugc_translator.cpp b/generator/ugc_translator.cpp
index c69d493a11..150a2af030 100644
--- a/generator/ugc_translator.cpp
+++ b/generator/ugc_translator.cpp
@@ -2,59 +2,14 @@
 
 #include "generator/ugc_db.hpp"
 
+#include "ugc/serdes_json.hpp"
+
 #include "coding/multilang_utf8_string.hpp"
 
 #include "base/string_utils.hpp"
 
 #include "3party/jansson/myjansson.hpp"
 
-namespace
-{
-void FillRatings(json_t const * ratings, ugc::Ratings & result)
-{
-  size_t size = json_array_size(ratings);
-  for (size_t i = 0; i < size; ++i)
-  {
-    json_t * el = json_array_get(ratings, i);
-    uint32_t id = 0;
-    double ratingValue = 0.;
-
-    FromJSONObject(el, "id", id);
-    FromJSONObject(el, "value", ratingValue);
-
-    result.emplace_back(strings::to_string(id), static_cast<float>(ratingValue));
-  }
-}
-
-void FillReviews(json_t const * reviews, ugc::Reviews & result)
-{
-  size_t size = json_array_size(reviews);
-  for (size_t i = 0; i < size; ++i)
-  {
-    ugc::Review review;
-
-    json_t * el = json_array_get(reviews, i);
-
-    uint32_t daysSinceEpoch = 0;
-    double rating = 0.;
-    std::string lang;
-
-    FromJSONObject(el, "id", review.m_id);
-    FromJSONObject(el, "text", review.m_text.m_text);
-    FromJSONObject(el, "lang", lang);
-    FromJSONObject(el, "author", review.m_author);
-    FromJSONObject(el, "rating", rating);
-    FromJSONObject(el, "date", daysSinceEpoch);
-
-    review.m_text.m_lang = StringUtf8Multilang::GetLangIndex(lang);
-    review.m_rating = rating;
-    review.m_time = ugc::Clock::now() - std::chrono::hours(daysSinceEpoch * 24);
-
-    result.push_back(std::move(review));
-  }
-}
-}  // namespace
-
 namespace generator
 {
 UGCTranslator::UGCTranslator() : m_db(":memory:") {}
@@ -64,43 +19,21 @@ UGCTranslator::UGCTranslator(std::string const & dbFilename) : m_db(dbFilename)
 bool UGCTranslator::TranslateUGC(osm::Id const & id, ugc::UGC & ugc)
 {
   std::vector<uint8_t> blob;
-  bool rc = m_db.Get(id, blob);
-  if (!rc)
-    return false;
-  std::string result(blob.cbegin(), blob.cend());
-
-  try
-  {
-    my::Json root(result);
-    double totalRating = 0.;
-
-    FromJSONObject(root.get(), "total_rating", totalRating);
-    FromJSONObject(root.get(), "votes", ugc.m_votes);
 
-    ugc.m_totalRating = totalRating;
+  if (!m_db.Get(id, blob))
+    return false;
 
-    auto const ratings = json_object_get(root.get(), "ratings");
-    auto const reviews = json_object_get(root.get(), "reviews");
+  std::string src(blob.cbegin(), blob.cend());
 
-    if (!CheckJsonArray(ratings) || !CheckJsonArray(reviews))
-      return false;
+  ugc::DeserializerJsonV0 des(src);
 
-    FillRatings(ratings, ugc.m_ratings);
-    FillReviews(reviews, ugc.m_reviews);
-  }
-  catch (my::Json::Exception const & e)
-  {
-    LOG(LERROR, (e.Msg()));
-    ugc = {};
-    return false;
-  }
+  des(ugc);
 
   return true;
 }
 
 void UGCTranslator::CreateDb(std::string const & data)
 {
-  bool rc = m_db.Exec(data);
-  UNUSED_VALUE(rc);
+  CHECK(m_db.Exec(data), ());
 }
 }  // namespace generator
diff --git a/partners_api/locals_api.cpp b/partners_api/locals_api.cpp
index fbde1d72c6..c061304d95 100644
--- a/partners_api/locals_api.cpp
+++ b/partners_api/locals_api.cpp
@@ -37,8 +37,6 @@ void ParseLocals(std::string const & src, std::vector<LocalExpert> & locals,
   hasPrevious = json_is_number(previousField);
   hasNext = json_is_number(nextField);
   auto const results = json_object_get(root.get(), "results");
-  if (!CheckJsonArray(results))
-    return;
   auto const dataSize = json_array_size(results);
   for (size_t i = 0; i < dataSize; ++i)
   {
diff --git a/partners_api/viator_api.cpp b/partners_api/viator_api.cpp
index 09b7bed3c6..ac8662971b 100644
--- a/partners_api/viator_api.cpp
+++ b/partners_api/viator_api.cpp
@@ -133,7 +133,7 @@ bool CheckAnswer(my::Json const & root)
     std::string errorMessage = "Unknown error.";
     auto const errorMessageArray = json_object_get(root.get(), "errorMessageText");
 
-    if (CheckJsonArray(errorMessageArray))
+    if (json_array_size(errorMessageArray))
       FromJSON(json_array_get(errorMessageArray, 0), errorMessage);
 
     LOG(LWARNING, ("Viator retrieved unsuccessfull status, error message:", errorMessage));
@@ -148,7 +148,7 @@ void MakeProducts(std::string const & src, std::vector<Product> & products)
 
   my::Json root(src.c_str());
   auto const data = json_object_get(root.get(), "data");
-  if (!CheckAnswer(root) || !CheckJsonArray(data))
+  if (!CheckAnswer(root) || !json_array_size(data))
     return;
 
   auto const dataSize = json_array_size(data);
diff --git a/ugc/api.cpp b/ugc/api.cpp
index 076df47507..523f47fc4d 100644
--- a/ugc/api.cpp
+++ b/ugc/api.cpp
@@ -1,5 +1,7 @@
 #include "ugc/api.hpp"
 
+#include "indexer/feature.hpp"
+
 #include "platform/platform.hpp"
 
 #include <chrono>
@@ -9,7 +11,11 @@ using namespace ugc;
 
 namespace ugc
 {
-Api::Api(Index const & index, std::string const & filename) : m_index(index), m_storage(filename) {}
+Api::Api(Index const & index, std::string const & filename)
+  : m_storage(filename)
+, m_loader(index)
+{
+}
 
 void Api::GetUGC(FeatureID const & id, UGCCallback callback)
 {
@@ -23,17 +29,18 @@ void Api::SetUGCUpdate(FeatureID const & id, UGCUpdate const & ugc)
 
 void Api::GetUGCImpl(FeatureID const & id, UGCCallback callback)
 {
-  // TODO (@y, @mgsergio): retrieve static UGC
-  UGC ugc;
-  UGCUpdate update;
-
   if (!id.IsValid())
   {
-    GetPlatform().RunOnGuiThread([ugc, update, callback] { callback(ugc, update); });
+    GetPlatform().RunOnGuiThread([callback] { callback({}, {}); });
     return;
   }
 
-  // ugc = MakeTestUGC1();
+  UGC ugc;
+  UGCUpdate update;
+
+  m_storage.GetUGCUpdate(id, update);
+  m_loader.GetUGC(id, ugc);
+
   GetPlatform().RunOnGuiThread([ugc, update, callback] { callback(ugc, update); });
 }
 
diff --git a/ugc/api.hpp b/ugc/api.hpp
index 4f578ce53e..a9b50777b2 100644
--- a/ugc/api.hpp
+++ b/ugc/api.hpp
@@ -2,6 +2,7 @@
 
 #include "base/worker_thread.hpp"
 
+#include "ugc/loader.hpp"
 #include "ugc/storage.hpp"
 #include "ugc/types.hpp"
 
@@ -28,8 +29,8 @@ private:
 
   void SetUGCUpdateImpl(FeatureID const & id, UGCUpdate const & ugc);
 
-  Index const & m_index;
   base::WorkerThread m_thread;
   Storage m_storage;
+  Loader m_loader;
 };
 }  // namespace ugc
diff --git a/ugc/binary/serdes.cpp b/ugc/binary/serdes.cpp
index fdecacaff8..b239b0edce 100644
--- a/ugc/binary/serdes.cpp
+++ b/ugc/binary/serdes.cpp
@@ -15,6 +15,8 @@ class BaseCollector
 public:
   virtual ~BaseCollector() = default;
 
+  void VisitVarUint(uint32_t, char const * /* name */ = nullptr) {}
+  void VisitVarUint(uint64_t, char const * /* name */ = nullptr) {}
   virtual void VisitRating(float const f, char const * /* name */ = nullptr) {}
   virtual void operator()(string const & /* s */, char const * /* name */ = nullptr) {}
   virtual void operator()(Sentiment const /* sentiment */, char const * /* name */ = nullptr) {}
diff --git a/ugc/loader.cpp b/ugc/loader.cpp
new file mode 100644
index 0000000000..b28d9e3461
--- /dev/null
+++ b/ugc/loader.cpp
@@ -0,0 +1,34 @@
+#include "ugc/loader.hpp"
+
+#include "ugc/types.hpp"
+
+#include "indexer/feature.hpp"
+#include "indexer/index.hpp"
+
+#include "defines.hpp"
+
+namespace ugc
+{
+Loader::Loader(Index const & index) : m_index(index) {}
+
+void Loader::GetUGC(FeatureID const & featureId, UGC & result)
+{
+  UGC ugc;
+  auto const & handle = m_index.GetMwmHandleById(featureId.m_mwmId);
+
+  if (!handle.IsAlive())
+    return;
+
+  auto const & value = *handle.GetValue<MwmValue>();
+
+  if (!value.m_cont.IsExist(UGC_FILE_TAG))
+    return;
+
+  auto readerPtr = value.m_cont.GetReader(UGC_FILE_TAG);
+
+  if (!m_d.Deserialize(*readerPtr.GetPtr(), featureId.m_index, ugc))
+    return;
+
+  result = std::move(ugc);
+}
+}  // namespace ugc
diff --git a/ugc/loader.hpp b/ugc/loader.hpp
new file mode 100644
index 0000000000..45e332bd0c
--- /dev/null
+++ b/ugc/loader.hpp
@@ -0,0 +1,22 @@
+#pragma once
+
+#include "ugc/binary/serdes.hpp"
+
+class Index;
+struct FeatureID;
+
+namespace ugc
+{
+struct UGC;
+
+class Loader
+{
+public:
+  Loader(Index const & index);
+  void GetUGC(FeatureID const & featureId, UGC & ugc);
+
+private:
+    Index const & m_index;
+    binary::UGCDeserializer m_d;
+};
+}  // namespace ugc
diff --git a/ugc/serdes_json.hpp b/ugc/serdes_json.hpp
index 7fc8f36e01..c850db6cbe 100644
--- a/ugc/serdes_json.hpp
+++ b/ugc/serdes_json.hpp
@@ -73,6 +73,12 @@ public:
     ToJSONObject(*m_json, name, d);
   }
 
+  template <typename T>
+  void VisitVarUint(T const & t, char const * name = nullptr)
+  {
+    ToJSONObject(*m_json, name, t);
+  }
+
 private:
   template <typename Fn>
   void NewScopeWith(my::JSONPtr json_object, char const * name, Fn && fn)
@@ -95,20 +101,28 @@ private:
   Sink & m_sink;
 };
 
-template <typename Source>
 class DeserializerJsonV0
 {
 public:
   DECLARE_EXCEPTION(Exception, RootException);
 
-  DeserializerJsonV0(Source & source) : m_source(source)
+  template <typename Source,
+            typename std::enable_if<
+              !std::is_convertible<Source, std::string>::value, Source>::type * = nullptr>
+  DeserializerJsonV0(Source & source)
   {
     std::string src(source.Size(), '\0');
     source.Read(static_cast<void *>(&src[0]), source.Size());
-    m_jsonObject.ParseFrom(src.c_str());
+    m_jsonObject.ParseFrom(src);
     m_json = m_jsonObject.get();
   }
 
+  DeserializerJsonV0(std::string const & source)
+    : m_jsonObject(source)
+    , m_json(m_jsonObject.get())
+  {
+  }
+
   void operator()(bool & d, char const * name = nullptr) { FromJSONObject(m_json, name, d); }
   void operator()(uint8_t & d, char const * name = nullptr) { FromJSONObject(m_json, name, d); }
   void operator()(uint32_t & d, char const * name = nullptr) { FromJSONObject(m_json, name, d); }
@@ -118,6 +132,7 @@ public:
   {
     (*this)(key.m_key, name);
   }
+
   void operator()(Time & t, char const * name = nullptr)
   {
     uint32_t d = 0;
@@ -167,6 +182,12 @@ public:
     f = static_cast<float>(d);
   }
 
+  template <typename T>
+  void VisitVarUint(T & t, char const * name = nullptr)
+  {
+    FromJSONObject(m_json, name, t);
+  }
+
 private:
   json_t * SaveContext(char const * name = nullptr)
   {
@@ -184,6 +205,5 @@ private:
 
   my::Json m_jsonObject;
   json_t * m_json = nullptr;
-  Source & m_source;
 };
 }  // namespace ugc
diff --git a/ugc/storage.cpp b/ugc/storage.cpp
index 15fd9babb6..fe966264a7 100644
--- a/ugc/storage.cpp
+++ b/ugc/storage.cpp
@@ -10,12 +10,13 @@ Storage::Storage(std::string const & filename)
   Load();
 }
 
-UGCUpdate const * Storage::GetUGCUpdate(FeatureID const & id) const
+void Storage::GetUGCUpdate(FeatureID const & id, UGCUpdate & ugc) const
 {
   auto const it = m_ugc.find(id);
-  if (it != end(m_ugc))
-    return &it->second;
-  return nullptr;
+  if (it == end(m_ugc))
+    return;
+
+  ugc = it->second;
 }
 
 void Storage::SetUGCUpdate(FeatureID const & id, UGCUpdate const & ugc)
diff --git a/ugc/storage.hpp b/ugc/storage.hpp
index 2086dbad15..c6df8c5f67 100644
--- a/ugc/storage.hpp
+++ b/ugc/storage.hpp
@@ -14,7 +14,7 @@ class Storage
 public:
   explicit Storage(std::string const & filename);
 
-  UGCUpdate const * GetUGCUpdate(FeatureID const & id) const;
+  void GetUGCUpdate(FeatureID const & id, UGCUpdate & ugc) const;
   void SetUGCUpdate(FeatureID const & id, UGCUpdate const & ugc);
 
   void Save();
diff --git a/ugc/types.hpp b/ugc/types.hpp
index 2e6f278756..fd60258bba 100644
--- a/ugc/types.hpp
+++ b/ugc/types.hpp
@@ -4,6 +4,7 @@
 
 #include "coding/hex.hpp"
 
+#include "base/math.hpp"
 #include "base/visitor.hpp"
 
 #include <chrono>
@@ -30,14 +31,14 @@ struct TranslationKey
   bool operator==(TranslationKey const & rhs) const { return m_key == rhs.m_key; }
   bool operator<(TranslationKey const & rhs) const { return m_key < rhs.m_key; }
 
-  friend std::string DebugPrint(TranslationKey const & key)
-  {
-    return "TranslationKey [ " + key.m_key + " ]";
-  }
-
   std::string m_key;
 };
 
+std::string DebugPrint(TranslationKey const & key)
+{
+  return "TranslationKey [ " + key.m_key + " ]";
+}
+
 enum class Sentiment
 {
   Positive,
@@ -86,18 +87,18 @@ struct RatingRecord
     return m_key == rhs.m_key && m_value == rhs.m_value;
   }
 
-  friend std::string DebugPrint(RatingRecord const & ratingRecord)
-  {
-    std::ostringstream os;
-    os << "RatingRecord [ " << DebugPrint(ratingRecord.m_key) << " " << ratingRecord.m_value
-       << " ]";
-    return os.str();
-  }
-
   TranslationKey m_key{};
   float m_value{};
 };
 
+std::string DebugPrint(RatingRecord const & ratingRecord)
+{
+  std::ostringstream os;
+  os << "RatingRecord [ " << DebugPrint(ratingRecord.m_key) << " " << ratingRecord.m_value
+     << " ]";
+  return os.str();
+}
+
 using Ratings = std::vector<RatingRecord>;
 
 struct UID
@@ -110,17 +111,18 @@ struct UID
   DECLARE_VISITOR(visitor(m_hi, "hi"), visitor(m_lo, "lo"));
 
   bool operator==(UID const & rhs) const { return m_hi == rhs.m_hi && m_lo == rhs.m_lo; }
-  friend std::string DebugPrint(UID const & uid)
-  {
-    std::ostringstream os;
-    os << "UID [ " << uid.ToString() << " ]";
-    return os.str();
-  }
 
   uint64_t m_hi{};
   uint64_t m_lo{};
 };
 
+std::string DebugPrint(UID const & uid)
+{
+  std::ostringstream os;
+  os << "UID [ " << uid.ToString() << " ]";
+  return os.str();
+}
+
 using Author = std::string;
 
 struct Text
@@ -132,18 +134,18 @@ struct Text
 
   bool operator==(Text const & rhs) const { return m_lang == rhs.m_lang && m_text == rhs.m_text; }
 
-  friend std::string DebugPrint(Text const & text)
-  {
-    std::ostringstream os;
-    os << "Text [ " << StringUtf8Multilang::GetLangByCode(text.m_lang) << ": " << text.m_text
-       << " ]";
-    return os.str();
-  }
-
   std::string m_text;
   uint8_t m_lang = StringUtf8Multilang::kDefaultCode;
 };
 
+std::string DebugPrint(Text const & text)
+{
+  std::ostringstream os;
+  os << "Text [ " << StringUtf8Multilang::GetLangByCode(text.m_lang) << ": " << text.m_text
+     << " ]";
+  return os.str();
+}
+
 struct Review
 {
   using ReviewId = uint64_t;
@@ -164,18 +166,6 @@ struct Review
            m_rating == rhs.m_rating && m_time == rhs.m_time;
   }
 
-  friend std::string DebugPrint(Review const & review)
-  {
-    std::ostringstream os;
-    os << "Review [ ";
-    os << "id:" << review.m_id << ", ";
-    os << "text:" << DebugPrint(review.m_text) << ", ";
-    os << "author:" << review.m_author << ", ";
-    os << "rating:" << review.m_rating << ", ";
-    os << "days since epoch:" << ToDaysSinceEpoch(review.m_time) << " ]";
-    return os.str();
-  }
-
   ReviewId m_id{};
   Text m_text{};
   Author m_author{};
@@ -183,6 +173,18 @@ struct Review
   Time m_time{};
 };
 
+std::string DebugPrint(Review const & review)
+{
+  std::ostringstream os;
+  os << "Review [ ";
+  os << "id:" << review.m_id << ", ";
+  os << "text:" << DebugPrint(review.m_text) << ", ";
+  os << "author:" << review.m_author << ", ";
+  os << "rating:" << review.m_rating << ", ";
+  os << "days since epoch:" << ToDaysSinceEpoch(review.m_time) << " ]";
+  return os.str();
+}
+
 using Reviews = std::vector<Review>;
 
 struct Attribute
@@ -199,49 +201,56 @@ struct Attribute
     return m_key == rhs.m_key && m_value == rhs.m_value;
   }
 
-  friend std::string DebugPrint(Attribute const & attribute)
-  {
-    std::ostringstream os;
-    os << "Attribute [ key:" << DebugPrint(attribute.m_key)
-       << ", value:" << DebugPrint(attribute.m_value) << " ]";
-    return os.str();
-  }
-
   TranslationKey m_key{};
   TranslationKey m_value{};
 };
 
+std::string DebugPrint(Attribute const & attribute)
+{
+  std::ostringstream os;
+  os << "Attribute [ key:" << DebugPrint(attribute.m_key)
+     << ", value:" << DebugPrint(attribute.m_value) << " ]";
+  return os.str();
+}
+
 struct UGC
 {
   UGC() = default;
-  UGC(Ratings const & records, Reviews const & reviews, float const totalRating, uint32_t votes)
-    : m_ratings(records), m_reviews(reviews), m_totalRating(totalRating), m_votes(votes)
+  UGC(Ratings const & records, Reviews const & reviews, float const totalRating, uint32_t basedOn)
+    : m_ratings(records), m_reviews(reviews), m_totalRating(totalRating), m_basedOn(basedOn)
   {
   }
 
   DECLARE_VISITOR(visitor(m_ratings, "ratings"), visitor(m_reviews, "reviews"),
-                  visitor.VisitRating(m_totalRating, "totalRating"))
+                  visitor.VisitRating(m_totalRating, "total_rating"),
+                  visitor.VisitVarUint(m_basedOn, "based_on"))
 
   bool operator==(UGC const & rhs) const
   {
-    return m_ratings == rhs.m_ratings && m_reviews == rhs.m_reviews;
+    return m_ratings == rhs.m_ratings && m_reviews == rhs.m_reviews &&
+        my::AlmostEqualAbs(m_totalRating, rhs.m_totalRating, 1e-6f) && m_basedOn == rhs.m_basedOn;
   }
 
-  friend std::string DebugPrint(UGC const & ugc)
+  bool IsValid() const
   {
-    std::ostringstream os;
-    os << "UGC [ ";
-    os << "records:" << ::DebugPrint(ugc.m_ratings) << ", ";
-    os << "reviews:" << ::DebugPrint(ugc.m_reviews) << " ]";
-    return os.str();
+    return (!m_ratings.empty() || !m_reviews.empty()) && m_totalRating > 1e-6 && m_basedOn > 0;
   }
 
   Ratings m_ratings;
   Reviews m_reviews;
   float m_totalRating{};
-  uint32_t m_votes{};
+  uint32_t m_basedOn{};
 };
 
+std::string DebugPrint(UGC const & ugc)
+{
+  std::ostringstream os;
+  os << "UGC [ ";
+  os << "records:" << ::DebugPrint(ugc.m_ratings) << ", ";
+  os << "reviews:" << ::DebugPrint(ugc.m_reviews) << " ]";
+  return os.str();
+}
+
 struct UGCUpdate
 {
   UGCUpdate() = default;
@@ -257,14 +266,9 @@ struct UGCUpdate
     return m_ratings == rhs.m_ratings && m_text == rhs.m_text && m_time == rhs.m_time;
   }
 
-  friend std::string DebugPrint(UGCUpdate const & ugcUpdate)
+  bool IsValid() const
   {
-    std::ostringstream os;
-    os << "UGCUpdate [ ";
-    os << "records:" << ::DebugPrint(ugcUpdate.m_ratings) << ", ";
-    os << "text:" << DebugPrint(ugcUpdate.m_text) << ", ";
-    os << "days since epoch:" << ToDaysSinceEpoch(ugcUpdate.m_time) << " ]";
-    return os.str();
+    return (!m_ratings.empty() || !m_text.m_text.empty()) && m_time != Time();
   }
 
   Ratings m_ratings;
@@ -272,6 +276,16 @@ struct UGCUpdate
   Time m_time{};
 };
 
+std::string DebugPrint(UGCUpdate const & ugcUpdate)
+{
+  std::ostringstream os;
+  os << "UGCUpdate [ ";
+  os << "records:" << ::DebugPrint(ugcUpdate.m_ratings) << ", ";
+  os << "text:" << DebugPrint(ugcUpdate.m_text) << ", ";
+  os << "days since epoch:" << ToDaysSinceEpoch(ugcUpdate.m_time) << " ]";
+  return os.str();
+}
+
 struct ReviewFeedback
 {
   ReviewFeedback() = default;
diff --git a/ugc/ugc.pro b/ugc/ugc.pro
index 3142108058..a08da10f90 100644
--- a/ugc/ugc.pro
+++ b/ugc/ugc.pro
@@ -15,11 +15,14 @@ HEADERS += \
     binary/serdes.hpp \
     binary/ugc_holder.hpp \
     binary/visitors.hpp \
+    loader.hpp \
     serdes.hpp \
+    serdes_json.hpp \
     storage.hpp \
     types.hpp \
 
 SOURCES += \
     api.cpp \
     binary/serdes.cpp \
+    loader.cpp \
     storage.cpp \
diff --git a/ugc/ugc_tests/serdes_tests.cpp b/ugc/ugc_tests/serdes_tests.cpp
index 6cdc967a7d..b3f5c0154f 100644
--- a/ugc/ugc_tests/serdes_tests.cpp
+++ b/ugc/ugc_tests/serdes_tests.cpp
@@ -22,7 +22,7 @@ using Buffer = vector<uint8_t>;
 using ToBin = Serializer<MemWriter<Buffer>>;
 using FromBin = DeserializerV0<ReaderSource<MemReader>>;
 using ToJson = SerializerJson<MemWriter<Buffer>>;
-using FromJson = DeserializerJsonV0<ReaderSource<MemReader>>;
+using FromJson = DeserializerJsonV0;
 
 Ratings GetTestRating()
 {
diff --git a/ugc/ugc_tests/utils.cpp b/ugc/ugc_tests/utils.cpp
index 0693173410..11b178df42 100644
--- a/ugc/ugc_tests/utils.cpp
+++ b/ugc/ugc_tests/utils.cpp
@@ -19,13 +19,13 @@ UGC MakeTestUGC1(Time now)
 
   Reviews reviews;
   reviews.emplace_back(20 /* id */, Text("Damn good coffee", StringUtf8Multilang::kEnglishCode),
-                       Author(UID(987654321 /* hi */, 123456789 /* lo */), "Cole"),
+                       Author("Cole"),
                        5.0 /* rating */, FromDaysAgo(now, 10));
   reviews.emplace_back(
       67812 /* id */, Text("Clean place, reasonably priced", StringUtf8Multilang::kDefaultCode),
-      Author(UID(0 /* hi */, 315 /* lo */), "Cooper"), 5.0 /* rating */, FromDaysAgo(now, 1));
+      Author("Cooper"), 5.0 /* rating */, FromDaysAgo(now, 1));
 
-  return UGC(records, reviews, 4.5 /* rating */);
+  return UGC(records, reviews, 4.5 /* rating */, 4000000000 /* votes */);
 }
 
 UGC MakeTestUGC2(Time now)
@@ -38,9 +38,9 @@ UGC MakeTestUGC2(Time now)
   vector<Review> reviews;
   reviews.emplace_back(
       119 /* id */, Text("This pie's so good it is a crime", StringUtf8Multilang::kDefaultCode),
-      Author(UID(0 /* hi */, 315 /* lo */), "Cooper"), 5.0 /* rating */, FromDaysAgo(now, 1));
+      Author("Cooper"), 5.0 /* rating */, FromDaysAgo(now, 1));
 
-  return UGC(records, reviews, 5.0 /* rating */);
+  return UGC(records, reviews, 5.0 /* rating */, 1 /* votes */);
 }
 
 UGCUpdate MakeTestUGCUpdate(Time now)
diff --git a/ugc/ugc_tests/utils.hpp b/ugc/ugc_tests/utils.hpp
index 82cb5b8588..cc4507bb8c 100644
--- a/ugc/ugc_tests/utils.hpp
+++ b/ugc/ugc_tests/utils.hpp
@@ -6,5 +6,6 @@ namespace ugc
 {
 UGC MakeTestUGC1(Time now = Clock::now());
 UGC MakeTestUGC2(Time now = Clock::now());
+
 UGCUpdate MakeTestUGCUpdate(Time now = Clock::now());
 }  // namespace ugc