Migrate ORC Writer to pylibcudf

[Matt711]

Description

Apart of #15162.

Checklist

• I am familiar with the Contributing Guidelines.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.

[wence-]

Small suggestions for cleanup, looks good to me.

[Matt711]

For the reviewer, c_obj is not usually accessed in the cudf._lib modules. I did it here because I didn't want to have to maintain a column_data attribute in TableInputMetadata. You'd have to "maintain" it because self.c_obj.column_metadata and self.column_metadata are different. Another approach is to have ColumnInMetadata's c_obj be a pointer. WDYT?

Here's what it looks like if ColumnInMetadata's c_obj` is a pointer.

diff --git a/python/pylibcudf/pylibcudf/io/types.pxd b/python/pylibcudf/pylibcudf/io/types.pxd
index 6e42c9c309..f8d1c515db 100644
--- a/python/pylibcudf/pylibcudf/io/types.pxd
+++ b/python/pylibcudf/pylibcudf/io/types.pxd
@@ -48,7 +48,7 @@ cdef class SinkInfo:
     cdef sink_info c_obj
 
 cdef class ColumnInMetadata:
-    cdef column_in_metadata c_obj
+    cdef column_in_metadata* c_obj
 
     cpdef ColumnInMetadata set_name(self, str name)
 
@@ -75,7 +75,7 @@ cdef class ColumnInMetadata:
     cpdef str get_name(self)
 
     @staticmethod
-    cdef ColumnInMetadata from_libcudf(column_in_metadata data)
+    cdef ColumnInMetadata from_libcudf(column_in_metadata* data)
 
 cdef class TableInputMetadata:
     cdef public Table table

and

diff --git a/python/pylibcudf/pylibcudf/io/types.pyx b/python/pylibcudf/pylibcudf/io/types.pyx
index c72fe3d4aa..f31f5c4d30 100644
--- a/python/pylibcudf/pylibcudf/io/types.pyx
+++ b/python/pylibcudf/pylibcudf/io/types.pyx
@@ -33,6 +33,7 @@ from pylibcudf.libcudf.io.types import (
     quote_style as QuoteStyle,  # no-cython-lint
     statistics_freq as StatisticsFreq, # no-cython-lint
 )
+from cython.operator cimport dereference
 
 __all__ = [
     "ColumnEncoding",
@@ -345,10 +346,10 @@ cdef class ColumnInMetadata:
         )
 
     @staticmethod
-    cdef ColumnInMetadata from_libcudf(column_in_metadata data):
+    cdef ColumnInMetadata from_libcudf(column_in_metadata* data):
         """Create a Python ColumnInMetadata from a libcudf column_in_metadata."""
         cdef ColumnInMetadata out = ColumnInMetadata.__new__(ColumnInMetadata)
-        out.c_obj = move(data)
+        out.c_obj = data
         return out
 
     cpdef ColumnInMetadata set_name(self, str name):
@@ -362,7 +363,7 @@ cdef class ColumnInMetadata:
         -------
         Self
         """
-        self.c_obj.set_name(name.encode())
+        dereference(self.c_obj).set_name(name.encode())
         return self

...
 
     cpdef ColumnInMetadata set_decimal_precision(self, int precision):
@@ -417,7 +418,7 @@ cdef class ColumnInMetadata:
         -------
         Self
         """
-        self.c_obj.set_decimal_precision(precision)
+        dereference(self.c_obj).set_decimal_precision(precision)
         return self
 
     cpdef ColumnInMetadata child(self, int i):
@@ -431,9 +432,8 @@ cdef class ColumnInMetadata:
         -------
         ColumnInMetadata
         """
-        return ColumnInMetadata.from_libcudf(
-            move(self.c_obj.child(i))
-        )
+        cdef column_in_metadata* child_c_obj = &dereference(self.c_obj).child(i)
+        return ColumnInMetadata.from_libcudf(child_c_obj)
 
...
 
 cdef class TableInputMetadata:
@@ -514,3 +514,8 @@ cdef class TableInputMetadata:
     """
     def __init__(self, Table table):
         self.c_obj = table_input_metadata(table.view())
+        self.column_metadata = []
+
+        cdef int num_columns = self.c_obj.column_metadata.size()
+        for i in range(num_columns):
+            self.column_metadata.append(ColumnInMetadata.from_libcudf(&self.c_obj.column_metadata[i]))

[Matt711]

I went ahead and made the change

[Matt711]

This PR uses changes from #17163 #17263, so it'd would be nice (but not necessary) to get those merged first.

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[Matt711]

/ok to test

[Matt711]

/ok to test

[Matt711]

Waiting on #17263, then I'll open this PR back up.

[Matt711]

/ok to test

[Matt711]

/ok to test

[Matt711]

/ok to test

[Matt711]

/ok to test

[Matt711]

/ok to test

[wence-]

Some small suggestions

[Matt711]

/ok to test

[Matt711]

/merge