From 275777743d01d0e347e571ae03b4e02eeda1a0da Mon Sep 17 00:00:00 2001
From: Ioannis Kavvadias <ioannis.kavvadias@redpanda.com>
Date: Tue, 21 Jan 2025 14:59:30 +0000
Subject: [PATCH] pandaproxy/sr: Add support for extention custom options

(cherry picked from commit f8c11ae7b79ff7e9b2b63394fe6180430c4fef10)
---
 src/v/pandaproxy/schema_registry/protobuf.cc         | 11 +++++++++++
 .../schema_registry/test/compatibility_protobuf.cc   | 12 +++++++++---
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/src/v/pandaproxy/schema_registry/protobuf.cc b/src/v/pandaproxy/schema_registry/protobuf.cc
index 205d5557256a4..0dc5dc8309a6b 100644
--- a/src/v/pandaproxy/schema_registry/protobuf.cc
+++ b/src/v/pandaproxy/schema_registry/protobuf.cc
@@ -637,6 +637,12 @@ struct protobuf_schema_definition::impl {
              boost::combine(from.enum_type(), *to.mutable_enum_type())) {
             copy_uninterpreted_options(enum_from, enum_to);
         }
+
+        // nested extentions
+        for (auto&& [extension_from, extension_to] :
+             boost::combine(from.extension(), *to.mutable_extension())) {
+            copy_uninterpreted_options(extension_from, extension_to);
+        }
     }
 
     void copy_uninterpreted_options(
@@ -680,6 +686,11 @@ struct protobuf_schema_definition::impl {
             copy_uninterpreted_options(enum_from, enum_to);
         }
 
+        for (auto&& [extension_from, extension_to] :
+             boost::combine(from.extension(), *to.mutable_extension())) {
+            copy_uninterpreted_options(extension_from, extension_to);
+        }
+
         for (auto&& [service_from, service_to] :
              boost::combine(from.service(), *to.mutable_service())) {
             copy_uninterpreted_options(service_from, service_to);
diff --git a/src/v/pandaproxy/schema_registry/test/compatibility_protobuf.cc b/src/v/pandaproxy/schema_registry/test/compatibility_protobuf.cc
index 7947ac2720164..3cec317eb431a 100644
--- a/src/v/pandaproxy/schema_registry/test/compatibility_protobuf.cc
+++ b/src/v/pandaproxy/schema_registry/test/compatibility_protobuf.cc
@@ -603,7 +603,7 @@ SEASTAR_THREAD_TEST_CASE(test_protobuf_normalize_custom_options) {
     auto schema = R"(import "google/protobuf/descriptor.proto";
 
 extend google.protobuf.FileOptions {
-  optional string my_file_option_b = 50008;
+  optional string my_file_option_b = 50008 [(my_field_option_b) = 5.5, (my_field_option_a) = 4.5];
   optional string my_file_option_a = 50000;
   repeated uint32 my_repeated_file_option = 60000;
 }
@@ -721,7 +721,10 @@ enum MyEnum {
   BAR = 2;
 }
 extend google.protobuf.FileOptions {
-  optional string my_file_option_b = 50008;
+  optional string my_file_option_b = 50008 [
+    (my_field_option_b) = 5.5,
+    (my_field_option_a) = 4.5
+  ];
   optional string my_file_option_a = 50000;
   repeated uint32 my_repeated_file_option = 60000;
 }
@@ -819,7 +822,10 @@ extend .google.protobuf.FieldOptions {
 }
 extend .google.protobuf.FileOptions {
   optional string my_file_option_a = 50000;
-  optional string my_file_option_b = 50008;
+  optional string my_file_option_b = 50008 [
+    (my_field_option_a) = 4.5,
+    (my_field_option_b) = 5.5
+  ];
   optional string my_file_option_c = 50015;
   repeated uint32 my_repeated_file_option = 60000;
 }