YT-19210: expose YQL shared library for YT.

After this, a new target libyqlplugin.so appears. in open-source cmake build.
Diff in open-source YDB repo looks like the following: https://paste.yandex-team.ru/f302bdb4-7ef2-4362-91c7-6ca45f329264

1 files changed, 268 insertions, 0 deletions

diff --git a/yt/cpp/mapreduce/interface/job_statistics.h b/yt/cpp/mapreduce/interface/job_statistics.h
new file mode 100644
index 0000000000..8af751604f
--- /dev/null
+++ b/yt/cpp/mapreduce/interface/job_statistics.h
@@ -0,0 +1,268 @@
+#pragma once
+
+///
+/// @file yt/cpp/mapreduce/interface/job_statistics.h
+///
+/// Header containing classes and utility functions to work with
+/// [job statistics](https://docs.yandex-team.ru/yt/problems/jobstatistics).
+
+#include "fwd.h"
+
+#include <library/cpp/yson/node/node.h>
+
+#include <util/system/defaults.h>
+#include <util/generic/maybe.h>
+#include <util/generic/ptr.h>
+
+namespace NYT {
+
+////////////////////////////////////////////////////////////////////
+
+///
+/// @brief Convert i64 representation of statistics to other type.
+///
+/// Library defines this template for types TDuration and i64.
+/// Users may define it for their types.
+///
+/// @see @ref NYT::TJobStatistics::GetStatisticsAs method.
+template <typename T>
+T ConvertJobStatisticsEntry(i64 value);
+
+////////////////////////////////////////////////////////////////////
+
+/// Class representing a collection of job statistics.
+class TJobStatistics
+{
+public:
+    ///
+    /// Construct empty statistics.
+    TJobStatistics();
+
+    ///
+    /// Construct statistics from statistics node.
+    TJobStatistics(const NYT::TNode& statistics);
+
+    TJobStatistics(const TJobStatistics& jobStatistics);
+    TJobStatistics(TJobStatistics&& jobStatistics);
+
+    TJobStatistics& operator=(const TJobStatistics& jobStatistics);
+    TJobStatistics& operator=(TJobStatistics&& jobStatistics);
+
+    ~TJobStatistics();
+
+    ///
+    /// @brief Filter statistics by task name.
+    ///
+    /// @param taskNames What task names to include (empty means all).
+    TJobStatistics TaskName(TVector<TTaskName> taskNames) const;
+
+    ///
+    /// @brief Filter statistics by job state.
+    ///
+    /// @param filter What job states to include (empty means all).
+    ///
+    /// @note Default statistics include only (successfully) completed jobs.
+    TJobStatistics JobState(TVector<EJobState> filter) const;
+
+    ///
+    /// @brief Filter statistics by job type.
+    ///
+    /// @param filter What job types to include (empty means all).
+    ///
+    /// @deprecated Use @ref TJobStatistics::TaskName instead.
+    ///
+    /// @see https://yt.yandex-team.ru/docs/description/mr/jobs#obshaya-shema
+    TJobStatistics JobType(TVector<EJobType> filter) const;
+
+    ///
+    /// @brief Check that given statistics exist.
+    ///
+    /// @param name Slash separated statistics name, e.g. "time/total" (like it appears in web interface).
+    bool HasStatistics(TStringBuf name) const;
+
+    ///
+    /// @brief Get statistics by name.
+    ///
+    /// @param name Slash separated statistics name, e.g. "time/total" (like it appears in web interface).
+    ///
+    /// @note If statistics is missing an exception is thrown. If because of filters
+    /// no fields remain the returned value is empty (all fields are `Nothing`).
+    ///
+    /// @note We don't use `TMaybe<TJobStatisticsEntry>` here;
+    /// instead, @ref NYT::TJobStatisticsEntry methods return `TMaybe<i64>`,
+    /// so user easier use `.GetOrElse`:
+    /// ```
+    ///     jobStatistics.GetStatistics("some/statistics/name").Max().GetOrElse(0);
+    /// ```
+    TJobStatisticsEntry<i64> GetStatistics(TStringBuf name) const;
+
+    ///
+    /// @brief Get statistics by name.
+    ///
+    /// @param name Slash separated statistics name, e.g. "time/total" (like it appears in web interface).
+    ///
+    /// @note In order to use `GetStatisticsAs` method, @ref NYT::ConvertJobStatisticsEntry function must be defined
+    /// (the library defines it for `i64` and `TDuration`, user may define it for other types).
+    template <typename T>
+    TJobStatisticsEntry<T> GetStatisticsAs(TStringBuf name) const;
+
+    ///
+    /// Get (slash separated) names of statistics.
+    TVector<TString> GetStatisticsNames() const;
+
+    ///
+    /// @brief Check if given custom statistics exists.
+    ///
+    /// @param name Slash separated custom statistics name.
+    bool HasCustomStatistics(TStringBuf name) const;
+
+    ///
+    /// @brief Get custom statistics (those the user can write in job with @ref NYT::WriteCustomStatistics).
+    ///
+    /// @param name Slash separated custom statistics name.
+    TJobStatisticsEntry<i64> GetCustomStatistics(TStringBuf name) const;
+
+    ///
+    /// @brief Get custom statistics (those the user can write in job with @ref NYT::WriteCustomStatistics).
+    ///
+    /// @param name Slash separated custom statistics name.
+    template <typename T>
+    TJobStatisticsEntry<T> GetCustomStatisticsAs(TStringBuf name) const;
+
+    ///
+    /// Get names of all custom statistics.
+    TVector<TString> GetCustomStatisticsNames() const;
+
+private:
+    class TData;
+    struct TFilter;
+
+    struct TDataEntry {
+        i64 Max;
+        i64 Min;
+        i64 Sum;
+        i64 Count;
+    };
+
+    static const TString CustomStatisticsNamePrefix_;
+
+private:
+    TJobStatistics(::TIntrusivePtr<TData> data, ::TIntrusivePtr<TFilter> filter);
+
+    TMaybe<TDataEntry> GetStatisticsImpl(TStringBuf name) const;
+
+private:
+    ::TIntrusivePtr<TData> Data_;
+    ::TIntrusivePtr<TFilter> Filter_;
+
+private:
+    template<typename T>
+    friend class TJobStatisticsEntry;
+};
+
+////////////////////////////////////////////////////////////////////
+
+/// Class representing single statistic.
+template <typename T>
+class TJobStatisticsEntry
+{
+public:
+    TJobStatisticsEntry(TMaybe<TJobStatistics::TDataEntry> data)
+        : Data_(std::move(data))
+    { }
+
+    /// Sum of the statistic over all jobs.
+    TMaybe<T> Sum() const
+    {
+        if (Data_) {
+            return ConvertJobStatisticsEntry<T>(Data_->Sum);
+        }
+        return Nothing();
+    }
+
+    /// @brief Average of the statistic over all jobs.
+    ///
+    /// @note Only jobs that emitted statistics are taken into account.
+    TMaybe<T> Avg() const
+    {
+        if (Data_ && Data_->Count) {
+            return ConvertJobStatisticsEntry<T>(Data_->Sum / Data_->Count);
+        }
+        return Nothing();
+    }
+
+    /// @brief Number of jobs that emitted this statistic.
+    TMaybe<T> Count() const
+    {
+        if (Data_) {
+            return ConvertJobStatisticsEntry<T>(Data_->Count);
+        }
+        return Nothing();
+    }
+
+    /// @brief Maximum value of the statistic over all jobs.
+    TMaybe<T> Max() const
+    {
+        if (Data_) {
+            return ConvertJobStatisticsEntry<T>(Data_->Max);
+        }
+        return Nothing();
+    }
+
+    /// @brief Minimum value of the statistic over all jobs.
+    TMaybe<T> Min() const
+    {
+        if (Data_) {
+            return ConvertJobStatisticsEntry<T>(Data_->Min);
+        }
+        return Nothing();
+    }
+
+private:
+    TMaybe<TJobStatistics::TDataEntry> Data_;
+
+private:
+    friend class TJobStatistics;
+};
+
+////////////////////////////////////////////////////////////////////
+
+template <typename T>
+TJobStatisticsEntry<T> TJobStatistics::GetStatisticsAs(TStringBuf name) const
+{
+    return TJobStatisticsEntry<T>(GetStatisticsImpl(name));
+}
+
+template <typename T>
+TJobStatisticsEntry<T> TJobStatistics::GetCustomStatisticsAs(TStringBuf name) const
+{
+    return TJobStatisticsEntry<T>(GetStatisticsImpl(CustomStatisticsNamePrefix_ + name));
+}
+
+////////////////////////////////////////////////////////////////////
+
+///
+/// @brief Write [custom statistics](https://yt.yandex-team.ru/docs/description/mr/jobs#user_stats).
+///
+/// @param path Slash-separated path (length must not exceed 512 bytes).
+/// @param value Value of the statistic.
+///
+/// @note The function must be called in job.
+/// Total number of statistics (with different paths) must not exceed 128.
+void WriteCustomStatistics(TStringBuf path, i64 value);
+
+///
+/// @brief Write several [custom statistics](https://yt.yandex-team.ru/docs/description/mr/jobs#user_stats) at once.
+///
+/// @param statistics A tree of map nodes with leaves of type `i64`.
+///
+/// @note The call is equivalent to calling @ref NYT::WriteCustomStatistics(TStringBuf, i64) for every path in the given map.
+void WriteCustomStatistics(const TNode& statistics);
+
+///
+/// @brief Flush [custom statistics stream](https://yt.yandex-team.ru/docs/description/mr/jobs#user_stats)
+///
+void FlushCustomStatisticsStream();
+////////////////////////////////////////////////////////////////////
+
+} // namespace NYT