YT-20969: C++ methods for reading table partitions

* Changelog entry
Type: feature
Component: cpp-mapreduce-sdk

Introduce methods for reading table partition
commit_hash:ab818edd21ccb2a9c5f3d5f010686c3314532192

1 files changed, 66 insertions, 0 deletions

diff --git a/yt/cpp/mapreduce/client/partition_reader.cpp b/yt/cpp/mapreduce/client/partition_reader.cpp
new file mode 100644
index 00000000000..1610a087cc9
--- /dev/null
+++ b/yt/cpp/mapreduce/client/partition_reader.cpp
@@ -0,0 +1,66 @@
+#include "partition_reader.h"
+
+#include <yt/cpp/mapreduce/common/retry_request.h>
+
+#include <yt/cpp/mapreduce/interface/raw_client.h>
+
+namespace NYT::NDetail {
+
+////////////////////////////////////////////////////////////////////////////////
+
+class TPartitionTableReader
+    : public TRawTableReader
+{
+public:
+    TPartitionTableReader(std::unique_ptr<IInputStream> input)
+        : Input_(std::move(input))
+    { }
+
+    bool Retry(
+        const TMaybe<ui32>& /*rangeIndex*/,
+        const TMaybe<ui64>& /*rowIndex*/,
+        const std::exception_ptr& /*error*/) override
+    {
+        return false;
+    }
+
+    void ResetRetries() override
+    { }
+
+    bool HasRangeIndices() const override
+    {
+        return false;
+    }
+
+protected:
+    size_t DoRead(void* buf, size_t len) override
+    {
+        return Input_->Read(buf, len);
+    }
+
+private:
+    std::unique_ptr<IInputStream> Input_;
+};
+
+////////////////////////////////////////////////////////////////////////////////
+
+TRawTableReaderPtr CreateTablePartitionReader(
+    const IRawClientPtr& rawClient,
+    const IRequestRetryPolicyPtr& retryPolicy,
+    const TString& cookie,
+    const TMaybe<TFormat>& format,
+    const TTablePartitionReaderOptions& options)
+{
+
+    auto stream = NDetail::RequestWithRetry<std::unique_ptr<IInputStream>>(
+        retryPolicy,
+        [&] (TMutationId /*mutationId*/) {
+            return rawClient->ReadTablePartition(cookie, format, options);
+        }
+    );
+    return MakeIntrusive<TPartitionTableReader>(std::move(stream));
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+} // namespace NYT::NDetail