From 2e401ed1edbde52df7f8ae100ecd0fcd4b596832 Mon Sep 17 00:00:00 2001
From: Giulio Eulisse <10544+ktf@users.noreply.github.com>
Date: Fri, 8 Aug 2025 09:16:26 +0200
Subject: [PATCH 1/2] WIP DPL Analysis: support BinaryView

The idea is to be able to have BinaryViews on top of the CCDB object
blobs which are already cached in shared memory, so that we can have
a simple table with rows of the kind:

(timestamp, blob-requested-ccdb-object-2, blob-requested-ccdb-object-2)

which then can be joined via the timestamp to provide access to the requested CCDB
Object.

Filling of the table via TableBuilder seems to work, retrieving the blobs currently crashes.
---
 Framework/Core/include/Framework/ArrowTypes.h |  5 +++
 .../Core/include/Framework/TableBuilder.h     | 34 ++++++++++++++++++-
 Framework/Core/test/test_TableBuilder.cxx     | 32 +++++++++++++++++
 3 files changed, 70 insertions(+), 1 deletion(-)

diff --git a/Framework/Core/include/Framework/ArrowTypes.h b/Framework/Core/include/Framework/ArrowTypes.h
index 69946b6f35a50..6fd70113fede7 100644
--- a/Framework/Core/include/Framework/ArrowTypes.h
+++ b/Framework/Core/include/Framework/ArrowTypes.h
@@ -12,6 +12,7 @@
 #ifndef O2_FRAMEWORK_ARROWTYPES_H
 #define O2_FRAMEWORK_ARROWTYPES_H
 #include "arrow/type_fwd.h"
+#include <span>
 
 namespace o2::soa
 {
@@ -62,6 +63,10 @@ template <>
 struct arrow_array_for<double> {
   using type = arrow::DoubleArray;
 };
+template <>
+struct arrow_array_for<std::span<std::byte>> {
+  using type = arrow::BinaryViewArray;
+};
 template <int N>
 struct arrow_array_for<float[N]> {
   using type = arrow::FixedSizeListArray;
diff --git a/Framework/Core/include/Framework/TableBuilder.h b/Framework/Core/include/Framework/TableBuilder.h
index eb56791acfd3c..0eaaa2bc1f949 100644
--- a/Framework/Core/include/Framework/TableBuilder.h
+++ b/Framework/Core/include/Framework/TableBuilder.h
@@ -98,6 +98,7 @@ O2_ARROW_STL_CONVERSION(long unsigned, UInt64Type)
 O2_ARROW_STL_CONVERSION(float, FloatType)
 O2_ARROW_STL_CONVERSION(double, DoubleType)
 O2_ARROW_STL_CONVERSION(std::string, StringType)
+O2_ARROW_STL_CONVERSION(std::span<std::byte>, BinaryViewType)
 } // namespace detail
 
 void addLabelToSchema(std::shared_ptr<arrow::Schema>& schema, const char* label);
@@ -274,6 +275,29 @@ struct BuilderMaker<bool> {
   }
 };
 
+template <>
+struct BuilderMaker<std::span<std::byte>> {
+  using FillType = std::span<std::byte>;
+  using STLValueType = std::span<std::byte>;
+  using ArrowType = typename detail::ConversionTraits<std::span<std::byte>>::ArrowType;
+  using BuilderType = typename arrow::TypeTraits<ArrowType>::BuilderType;
+
+  static std::unique_ptr<BuilderType> make(arrow::MemoryPool* pool)
+  {
+    return std::make_unique<BuilderType>(pool);
+  }
+
+  static std::shared_ptr<arrow::DataType> make_datatype()
+  {
+    return arrow::TypeTraits<ArrowType>::type_singleton();
+  }
+
+  static arrow::Status append(BuilderType& builder, std::span<std::byte> value)
+  {
+    return builder.Append((char*)value.data(), (int64_t)value.size());
+  }
+};
+
 template <typename ITERATOR>
 struct BuilderMaker<std::pair<ITERATOR, ITERATOR>> {
   using FillType = std::pair<ITERATOR, ITERATOR>;
@@ -338,6 +362,7 @@ struct BuilderMaker<T[N]> {
   }
 };
 
+
 template <typename T, int N>
 struct BuilderMaker<std::array<T, N>> {
   using FillType = T*;
@@ -422,6 +447,13 @@ struct DirectInsertion {
     return builder->Append(value);
   }
 
+  template <typename BUILDER>
+    requires std::same_as<std::span<std::byte>, T>
+  arrow::Status append(BUILDER& builder, T value)
+  {
+    return builder->Append((char*)value.data(), (int64_t)value.size());
+  }
+
   template <typename BUILDER>
   arrow::Status flush(BUILDER&)
   {
@@ -569,7 +601,7 @@ template <typename... ARGS>
 using IndexedHoldersTuple = decltype(makeHolderTypes<ARGS...>());
 
 template <typename T>
-concept ShouldNotDeconstruct = std::is_bounded_array_v<T> || std::is_arithmetic_v<T> || framework::is_base_of_template_v<std::vector, T>;
+concept ShouldNotDeconstruct = std::is_bounded_array_v<T> || std::is_arithmetic_v<T> || framework::is_base_of_template_v<std::vector, T> || std::same_as<std::span<std::byte>, T>;
 
 /// Helper class which creates a lambda suitable for building
 /// an arrow table from a tuple. This can be used, for example
diff --git a/Framework/Core/test/test_TableBuilder.cxx b/Framework/Core/test/test_TableBuilder.cxx
index 00cbbbc59b725..a42fe01511892 100644
--- a/Framework/Core/test/test_TableBuilder.cxx
+++ b/Framework/Core/test/test_TableBuilder.cxx
@@ -19,6 +19,9 @@
 #include <arrow/ipc/writer.h>
 #include <arrow/ipc/reader.h>
 
+#include <iostream>
+#include <string_view>
+
 using namespace o2::framework;
 
 // We use a different namespace to avoid clashes with the
@@ -27,10 +30,12 @@ namespace test2
 {
 DECLARE_SOA_COLUMN_FULL(X, x, uint64_t, "x");
 DECLARE_SOA_COLUMN_FULL(Y, y, uint64_t, "y");
+DECLARE_SOA_COLUMN_FULL(Blob, blob, std::span<std::byte>, "blob");
 DECLARE_SOA_COLUMN_FULL(Pos, pos, int[4], "pos");
 } // namespace test2
 
 using TestTable = o2::soa::InPlaceTable<0, test2::X, test2::Y>;
+using SpanTable = o2::soa::InPlaceTable<0, test2::Blob>;
 using ArrayTable = o2::soa::InPlaceTable<0, test2::Pos>;
 
 TEST_CASE("TestTableBuilder")
@@ -189,6 +194,32 @@ TEST_CASE("TestTableBuilderMore")
   REQUIRE(table->schema()->field(3)->type()->id() == arrow::boolean()->id());
 }
 
+TEST_CASE("TestSpan")
+{
+  TableBuilder builder;
+  std::vector<std::byte> buffer{10, std::byte{'c'}};
+  std::vector<std::byte> buffer1{10, std::byte{'a'}};
+
+  auto rowWriter = builder.persist<std::span<std::byte>>({"blob"});
+  rowWriter(0, std::span(buffer));
+  rowWriter(0, std::span(buffer));
+  rowWriter(0, std::span(buffer1.data(), 3));
+  rowWriter(0, std::span(buffer1.data(), 1));
+  auto table = builder.finalize();
+
+  REQUIRE(table->num_columns() == 1);
+  REQUIRE(table->num_rows() == 4);
+  REQUIRE(table->schema()->field(0)->name() == "blob");
+  REQUIRE(table->schema()->field(0)->type()->id() == arrow::binary_view()->id());
+
+  std::cout << table->ToString() << std::endl;
+
+  auto readBack = SpanTable{table};
+  for (auto& row : readBack) {
+    std::cout << row.blob().size() << std::endl;
+  }
+}
+
 TEST_CASE("TestSoAIntegration")
 {
   TableBuilder builder;
@@ -240,6 +271,7 @@ TEST_CASE("TestPodInjestion")
   }
 }
 
+
 TEST_CASE("TestColumnCount")
 {
   struct Foo {

From 6ea5056f061db7d42a58cf5cc20464ead20a72a8 Mon Sep 17 00:00:00 2001
From: ALICE Action Bot <alibuild@cern.ch>
Date: Fri, 8 Aug 2025 07:20:23 +0000
Subject: [PATCH 2/2] Please consider the following formatting changes

---
 Framework/Core/include/Framework/TableBuilder.h | 1 -
 Framework/Core/test/test_TableBuilder.cxx       | 1 -
 2 files changed, 2 deletions(-)

diff --git a/Framework/Core/include/Framework/TableBuilder.h b/Framework/Core/include/Framework/TableBuilder.h
index 0eaaa2bc1f949..74395a2680077 100644
--- a/Framework/Core/include/Framework/TableBuilder.h
+++ b/Framework/Core/include/Framework/TableBuilder.h
@@ -362,7 +362,6 @@ struct BuilderMaker<T[N]> {
   }
 };
 
-
 template <typename T, int N>
 struct BuilderMaker<std::array<T, N>> {
   using FillType = T*;
diff --git a/Framework/Core/test/test_TableBuilder.cxx b/Framework/Core/test/test_TableBuilder.cxx
index a42fe01511892..b6fc96e377fdb 100644
--- a/Framework/Core/test/test_TableBuilder.cxx
+++ b/Framework/Core/test/test_TableBuilder.cxx
@@ -271,7 +271,6 @@ TEST_CASE("TestPodInjestion")
   }
 }
 
-
 TEST_CASE("TestColumnCount")
 {
   struct Foo {