GH-44063: [Python] Deprecate the no longer used serialize/deserialize…

… Pyarrow C++ functions (#44064)

### Rationale for this change

We want to remove this part of the code (since we no longer use it ourselves, see #43587), and before doing that first deprecating them for two releases.

* GitHub Issue: #44063

Authored-by: Joris Van den Bossche <[email protected]>
Signed-off-by: Joris Van den Bossche <[email protected]>

python/pyarrow/src/arrow/python/deserialize.h

@@ -24,6 +24,7 @@
 #include "arrow/python/serialize.h"
 #include "arrow/python/visibility.h"
 #include "arrow/status.h"
+#include "arrow/util/macros.h"
 
 namespace arrow {
 
@@ -55,6 +56,7 @@ struct ARROW_PYTHON_EXPORT SparseTensorCounts {
 /// \param[in] src a RandomAccessFile
 /// \param[out] out the reconstructed data
 /// \return Status
+ARROW_DEPRECATED("Deprecated in 18.0.0. Will be removed in 20.0.0")
 ARROW_PYTHON_EXPORT
 Status ReadSerializedObject(io::RandomAccessFile* src, SerializedPyObject* out);
 
@@ -70,6 +72,7 @@ Status ReadSerializedObject(io::RandomAccessFile* src, SerializedPyObject* out);
 /// num_csf_tensors * (2 * ndim_csf + 3) + num_buffers in length
 /// \param[out] out the reconstructed object
 /// \return Status
+ARROW_DEPRECATED("Deprecated in 18.0.0. Will be removed in 20.0.0")
 ARROW_PYTHON_EXPORT
 Status GetSerializedFromComponents(int num_tensors,
                                    const SparseTensorCounts& num_sparse_tensors,
@@ -88,6 +91,7 @@ Status GetSerializedFromComponents(int num_tensors,
 /// \param[out] out The returned object
 /// \return Status
 /// This acquires the GIL
+ARROW_DEPRECATED("Deprecated in 18.0.0. Will be removed in 20.0.0")
 ARROW_PYTHON_EXPORT
 Status DeserializeObject(PyObject* context, const SerializedPyObject& object,
                          PyObject* base, PyObject** out);
@@ -96,9 +100,11 @@ Status DeserializeObject(PyObject* context, const SerializedPyObject& object,
 /// \param[in] object Object to deserialize
 /// \param[out] out The deserialized tensor
 /// \return Status
+ARROW_DEPRECATED("Deprecated in 18.0.0. Will be removed in 20.0.0")
 ARROW_PYTHON_EXPORT
 Status DeserializeNdarray(const SerializedPyObject& object, std::shared_ptr<Tensor>* out);
 
+ARROW_DEPRECATED("Deprecated in 18.0.0. Will be removed in 20.0.0")
 ARROW_PYTHON_EXPORT
 Status NdarrayFromBuffer(std::shared_ptr<Buffer> src, std::shared_ptr<Tensor>* out);
 

python/pyarrow/src/arrow/python/serialize.h

@@ -24,6 +24,7 @@
 #include "arrow/python/visibility.h"
 #include "arrow/sparse_tensor.h"
 #include "arrow/status.h"
+#include "arrow/util/macros.h"
 
 // Forward declaring PyObject, see
 // https://mail.python.org/pipermail/python-dev/2003-August/037601.html
@@ -92,13 +93,15 @@ struct ARROW_PYTHON_EXPORT SerializedPyObject {
 /// \return Status
 ///
 /// Release GIL before calling
+ARROW_DEPRECATED("Deprecated in 18.0.0. Will be removed in 20.0.0")
 ARROW_PYTHON_EXPORT
 Status SerializeObject(PyObject* context, PyObject* sequence, SerializedPyObject* out);
 
 /// \brief Serialize an Arrow Tensor as a SerializedPyObject.
 /// \param[in] tensor Tensor to be serialized
 /// \param[out] out The serialized representation
 /// \return Status
+ARROW_DEPRECATED("Deprecated in 18.0.0. Will be removed in 20.0.0")
 ARROW_PYTHON_EXPORT
 Status SerializeTensor(std::shared_ptr<Tensor> tensor, py::SerializedPyObject* out);
 
@@ -108,6 +111,7 @@ Status SerializeTensor(std::shared_ptr<Tensor> tensor, py::SerializedPyObject* o
 /// \param[in] tensor_num_bytes The length of the Tensor data in bytes
 /// \param[in] dst The OutputStream to write the Tensor header to
 /// \return Status
+ARROW_DEPRECATED("Deprecated in 18.0.0. Will be removed in 20.0.0")
 ARROW_PYTHON_EXPORT
 Status WriteNdarrayHeader(std::shared_ptr<DataType> dtype,
                           const std::vector<int64_t>& shape, int64_t tensor_num_bytes,