From 1ed4e1b84745f4c14f71d6394c1bccc0d7a26af7 Mon Sep 17 00:00:00 2001
From: Nikolai Kochetov <nk@clickhouse.com>
Date: Fri, 30 Aug 2024 16:52:42 +0000
Subject: [PATCH] Serialization of sort description.

---
 src/Core/SortDescription.cpp | 59 ++++++++++++++++++++++++++++++++++++
 src/Core/SortDescription.h   |  7 +++++
 2 files changed, 66 insertions(+)

diff --git a/src/Core/SortDescription.cpp b/src/Core/SortDescription.cpp
index 1b3f81f8547..01f22b9b9e5 100644
--- a/src/Core/SortDescription.cpp
+++ b/src/Core/SortDescription.cpp
@@ -15,6 +15,11 @@
 namespace DB
 {
 
+namespace ErrorCodes
+{
+    extern const int NOT_IMPLEMENTED;
+}
+
 void dumpSortDescription(const SortDescription & description, WriteBuffer & out)
 {
     bool first = true;
@@ -209,4 +214,58 @@ JSONBuilder::ItemPtr explainSortDescription(const SortDescription & description)
     return json_array;
 }
 
+void serializeSortDescription(const SortDescription & sort_description, WriteBuffer & out)
+{
+    writeVarUInt(sort_description.size(), out);
+    for (const auto & desc : sort_description)
+    {
+        writeStringBinary(desc.column_name, out);
+
+        UInt8 flags = 0;
+        if (desc.direction > 0)
+            flags |= 1;
+        if (desc.nulls_direction > 0)
+            flags |= 2;
+        if (desc.collator)
+            flags |= 4;
+        if (desc.with_fill)
+            flags |= 8;
+
+        writeIntBinary(flags, out);
+
+        if (desc.collator)
+            writeStringBinary(desc.collator->getLocale(), out);
+
+        if (desc.with_fill)
+            throw Exception(ErrorCodes::NOT_IMPLEMENTED, "WITH FILL is not supported in serialized sort description");
+    }
+}
+
+void deserializeSortDescription(SortDescription & sort_description, ReadBuffer & in)
+{
+    size_t size = 0;
+    readVarUInt(size, in);
+    sort_description.resize(size);
+    for (auto & desc : sort_description)
+    {
+        readStringBinary(desc.column_name, in);
+        UInt8 flags = 0;
+        readIntBinary(flags, in);
+
+        desc.direction = (flags & 1) ? 1 : -1;
+        desc.nulls_direction = (flags & 2) ? 1 : -1;
+
+        if (flags & 4)
+        {
+            String collator_locale;
+            readStringBinary(collator_locale, in);
+            if (!collator_locale.empty())
+                desc.collator = std::make_shared<Collator>(collator_locale);
+        }
+
+        if (flags & 8)
+            throw Exception(ErrorCodes::NOT_IMPLEMENTED, "WITH FILL is not supported in deserialized sort description");
+    }
+}
+
 }
diff --git a/src/Core/SortDescription.h b/src/Core/SortDescription.h
index 5c6f3e3150a..a87872193eb 100644
--- a/src/Core/SortDescription.h
+++ b/src/Core/SortDescription.h
@@ -140,4 +140,11 @@ void dumpSortDescription(const SortDescription & description, WriteBuffer & out)
 std::string dumpSortDescription(const SortDescription & description);
 
 JSONBuilder::ItemPtr explainSortDescription(const SortDescription & description);
+
+class WriteBuffer;
+class ReadBuffer;
+
+void serializeSortDescription(const SortDescription & sort_description, WriteBuffer & out);
+void deserializeSortDescription(SortDescription & sort_description, ReadBuffer & in);
+
 }