YT-19324: move YT provider to ydb/library/yql

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This commit has zero effect on all projects that depend on YQL.

The summary of changes:
- `yql/providers/yt -> ydb/library/yql/providers/yt `- the whole implementation of YT provider is moved into YDB code base for further export as a part of YT YQL plugin shared library;
- `yql/providers/stat/{expr_nodes,uploader} -> ydb/library/yql/providers/stat/{expr_nodes,uploader}` - a small interface without implementation and the description of stat expr nodes;
- `yql/core/extract_predicate/ut -> ydb/library/yql/core/extract_predicate/ut`;
- `yql/core/{ut,ut_common} -> ydb/library/yql/core/{ut,ut_common}`;
- `yql/core` is gone;
- `yql/library/url_preprocessing -> ydb/library/yql/core/url_preprocessing`.

**NB**: all new targets inside `ydb/` are under `IF (NOT CMAKE_EXPORT)` clause which disables them from open-source cmake generation and ya make build. They will be enabled in the subsequent commits.

1 files changed, 112 insertions, 0 deletions

diff --git a/yt/cpp/mapreduce/client/py_helpers.cpp b/yt/cpp/mapreduce/client/py_helpers.cpp
new file mode 100644
index 00000000000..3072449866e
--- /dev/null
+++ b/yt/cpp/mapreduce/client/py_helpers.cpp
@@ -0,0 +1,112 @@
+#include "py_helpers.h"
+
+#include "client.h"
+#include "operation.h"
+#include "transaction.h"
+
+#include <yt/cpp/mapreduce/interface/client.h>
+#include <yt/cpp/mapreduce/interface/fluent.h>
+
+#include <yt/cpp/mapreduce/common/retry_lib.h>
+#include <yt/cpp/mapreduce/common/helpers.h>
+
+#include <library/cpp/yson/node/node_io.h>
+
+#include <util/generic/hash_set.h>
+
+namespace NYT {
+
+using namespace NDetail;
+
+////////////////////////////////////////////////////////////////////////////////
+
+IStructuredJobPtr ConstructJob(const TString& jobName, const TString& state)
+{
+    auto node = TNode();
+    if (!state.empty()) {
+        node = NodeFromYsonString(state);
+    }
+    return TJobFactory::Get()->GetConstructingFunction(jobName.data())(node);
+}
+
+TString GetJobStateString(const IStructuredJob& job)
+{
+    TString result;
+    {
+        TStringOutput output(result);
+        job.Save(output);
+        output.Finish();
+    }
+    return result;
+}
+
+TStructuredJobTableList NodeToStructuredTablePaths(const TNode& node, const TOperationPreparer& preparer)
+{
+    int intermediateTableCount = 0;
+    TVector<TRichYPath> paths;
+    for (const auto& inputNode : node.AsList()) {
+        if (inputNode.IsNull()) {
+            ++intermediateTableCount;
+        } else {
+            paths.emplace_back(inputNode.AsString());
+        }
+    }
+    paths = NRawClient::CanonizeYPaths(/* retryPolicy */ nullptr, preparer.GetContext(), paths);
+    TStructuredJobTableList result(intermediateTableCount, TStructuredJobTable::Intermediate(TUnspecifiedTableStructure()));
+    for (const auto& path : paths) {
+        result.emplace_back(TStructuredJobTable{TUnspecifiedTableStructure(), path});
+    }
+    return result;
+}
+
+TString GetIOInfo(
+    const IStructuredJob& job,
+    const TCreateClientOptions& options,
+    const TString& cluster,
+    const TString& transactionId,
+    const TString& inputPaths,
+    const TString& outputPaths,
+    const TString& neededColumns)
+{
+    auto client = NDetail::CreateClientImpl(cluster, options);
+    TOperationPreparer preparer(client, GetGuid(transactionId));
+
+    auto structuredInputs = NodeToStructuredTablePaths(NodeFromYsonString(inputPaths), preparer);
+    auto structuredOutputs = NodeToStructuredTablePaths(NodeFromYsonString(outputPaths), preparer);
+
+    auto neededColumnsNode = NodeFromYsonString(neededColumns);
+    THashSet<TString> columnsUsedInOperations;
+    for (const auto& columnNode : neededColumnsNode.AsList()) {
+        columnsUsedInOperations.insert(columnNode.AsString());
+    }
+
+    auto operationIo = CreateSimpleOperationIoHelper(
+        job,
+        preparer,
+        TOperationOptions(),
+        std::move(structuredInputs),
+        std::move(structuredOutputs),
+        TUserJobFormatHints(),
+        ENodeReaderFormat::Yson,
+        columnsUsedInOperations);
+
+    return BuildYsonStringFluently().BeginMap()
+        .Item("input_format").Value(operationIo.InputFormat.Config)
+        .Item("output_format").Value(operationIo.OutputFormat.Config)
+        .Item("input_table_paths").List(operationIo.Inputs)
+        .Item("output_table_paths").List(operationIo.Outputs)
+        .Item("small_files").DoListFor(
+            operationIo.JobFiles.begin(),
+            operationIo.JobFiles.end(),
+            [] (TFluentList fluent, auto fileIt) {
+                fluent.Item().BeginMap()
+                    .Item("file_name").Value(fileIt->FileName)
+                    .Item("data").Value(fileIt->Data)
+                .EndMap();
+            })
+    .EndMap();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+} // namespace NYT