From f00853f39235a5eaef71595eab4548f5960ab746 Mon Sep 17 00:00:00 2001
From: Joris Van den Bossche <jorisvandenbossche@gmail.com>
Date: Wed, 24 May 2023 15:31:05 +0200
Subject: [PATCH] GH-34031: [Python][DRAFT] Experiment with PyCapsule for
 communicating C Data Interface pointers

---
 python/pyarrow/ipc.pxi | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/python/pyarrow/ipc.pxi b/python/pyarrow/ipc.pxi
index a8398597fe6..f86f3261fb7 100644
--- a/python/pyarrow/ipc.pxi
+++ b/python/pyarrow/ipc.pxi
@@ -17,7 +17,7 @@
 
 from collections import namedtuple
 import warnings
-
+cimport cpython
 
 cpdef enum MetadataVersion:
     V1 = <char> CMetadataVersion_V1
@@ -814,6 +814,29 @@ cdef class RecordBatchReader(_Weakrefable):
         self.reader = c_reader
         return self
 
+    @staticmethod
+    def _import_from_c_capsule(stream):
+        cdef:
+            ArrowArrayStream* c_stream
+            shared_ptr[CRecordBatchReader] c_reader
+            RecordBatchReader self
+
+        # sanity checks
+        if not cpython.PyCapsule_IsValid(stream, 'arrowarraystream'):
+            raise ValueError(
+                "Not an ArrayArrayStream object"
+            )
+        c_stream = <ArrowArrayStream*>cpython.PyCapsule_GetPointer(
+            stream, 'arrowarraystream'
+        )
+
+        with nogil:
+            c_reader = GetResultValue(ImportRecordBatchReader(c_stream))
+
+        self = RecordBatchReader.__new__(RecordBatchReader)
+        self.reader = c_reader
+        return self
+
     @staticmethod
     def from_batches(Schema schema not None, batches):
         """