diff --git a/ros2bag/ros2bag/verb/info.py b/ros2bag/ros2bag/verb/info.py
index 005c4b0ea..d101c0c52 100644
--- a/ros2bag/ros2bag/verb/info.py
+++ b/ros2bag/ros2bag/verb/info.py
@@ -45,6 +45,6 @@ def main(self, *, args):  # noqa: D102
             Info().print_output_verbose(args.bag_path, m, args.sort)
         else:
             if args.topic_name:
-                Info().print_output_topic_name_only(m)
+                Info().print_output_topic_name_only(m, args.sort)
             else:
                 Info().print_output(m, args.sort)
diff --git a/rosbag2_py/CMakeLists.txt b/rosbag2_py/CMakeLists.txt
index feb07925f..781fb3387 100644
--- a/rosbag2_py/CMakeLists.txt
+++ b/rosbag2_py/CMakeLists.txt
@@ -86,6 +86,7 @@ pybind11_add_module(_info SHARED
   src/rosbag2_py/_info.cpp
   src/rosbag2_py/format_bag_metadata.cpp
   src/rosbag2_py/format_service_info.cpp
+  src/rosbag2_py/info_sorting_method.cpp
 )
 target_link_libraries(_info PUBLIC
   rosbag2_cpp::rosbag2_cpp
diff --git a/rosbag2_py/src/rosbag2_py/_info.cpp b/rosbag2_py/src/rosbag2_py/_info.cpp
index 8fd39d69b..7b5d0473d 100644
--- a/rosbag2_py/src/rosbag2_py/_info.cpp
+++ b/rosbag2_py/src/rosbag2_py/_info.cpp
@@ -18,6 +18,7 @@
 #include <algorithm>
 #include <numeric>
 
+#include "info_sorting_method.hpp"
 #include "format_bag_metadata.hpp"
 #include "format_service_info.hpp"
 #include "rosbag2_cpp/info.hpp"
@@ -30,11 +31,6 @@ namespace rosbag2_py
 {
 
 
-std::unordered_map<std::string, SortingMethod> stringToSortingMethod = {
-  {"name", SortingMethod::NAME},
-  {"type", SortingMethod::TYPE},
-  {"count", SortingMethod::COUNT}};
-
 class Info
 {
 public:
@@ -51,28 +47,23 @@ class Info
   }
 
   void print_output(
-    const rosbag2_storage::BagMetadata & metadata_info, std::string sorting_method)
+    const rosbag2_storage::BagMetadata & metadata_info, const std::string & sorting_method)
   {
-    rosbag2_py::SortingMethod sort_method = rosbag2_py::stringToSortingMethod[sorting_method];
+    InfoSortingMethod sort_method = info_sorting_method_from_string(sorting_method);
     // Output formatted metadata
     std::cout << format_bag_meta_data(metadata_info, {}, false, false, sort_method) << std::endl;
   }
 
-  void print_output_topic_name_only(const rosbag2_storage::BagMetadata & metadata_info)
+  void print_output_topic_name_only(
+    const rosbag2_storage::BagMetadata & metadata_info, const std::string & sorting_method)
   {
-    std::vector<size_t> sorted_idx(metadata_info.topics_with_message_count.size());
-    std::iota(sorted_idx.begin(), sorted_idx.end(), 0);
-    std::sort(
-      sorted_idx.begin(),
-      sorted_idx.end(),
-      [&metadata_info](size_t i1, size_t i2) {
-        std::string topic_name_1 = metadata_info.topics_with_message_count[i1].topic_metadata.name;
-        std::string topic_name_2 = metadata_info.topics_with_message_count[i2].topic_metadata.name;
-        return topic_name_1 < topic_name_2;
-      }
-    );
+    InfoSortingMethod sort_method = info_sorting_method_from_string(sorting_method);
+    std::vector<size_t> sorted_idx = generate_sorted_idx(
+      metadata_info.topics_with_message_count,
+      sort_method);
+
     for (auto idx : sorted_idx) {
-      auto topic_info = metadata_info.topics_with_message_count[idx];
+      const auto & topic_info = metadata_info.topics_with_message_count[idx];
       if (!rosbag2_cpp::is_service_event_topic(
           topic_info.topic_metadata.name,
           topic_info.topic_metadata.type))
@@ -85,7 +76,7 @@ class Info
   void print_output_verbose(
     const std::string & uri,
     const rosbag2_storage::BagMetadata & metadata_info,
-    std::string sorting_method)
+    const std::string & sorting_method)
   {
     std::vector<std::shared_ptr<rosbag2_cpp::rosbag2_service_info_t>> all_services_info;
     for (auto & file_info : metadata_info.files) {
@@ -110,7 +101,7 @@ class Info
       }
     }
 
-    rosbag2_py::SortingMethod sort_method = rosbag2_py::stringToSortingMethod[sorting_method];
+    rosbag2_py::InfoSortingMethod sort_method = info_sorting_method_from_string(sorting_method);
     // Output formatted metadata and service info
     std::cout << format_bag_meta_data(metadata_info, messages_size, true, true, sort_method);
     std::cout << format_service_info(all_services_info, messages_size, true) << std::endl;
@@ -119,7 +110,7 @@ class Info
   std::unordered_set<std::string> get_sorting_methods()
   {
     std::unordered_set<std::string> sorting_methods;
-    for (auto sorting_method : rosbag2_py::stringToSortingMethod) {
+    for (auto sorting_method : rosbag2_py::sorting_method_map) {
       sorting_methods.insert(sorting_method.first);
     }
     return sorting_methods;
diff --git a/rosbag2_py/src/rosbag2_py/format_bag_metadata.cpp b/rosbag2_py/src/rosbag2_py/format_bag_metadata.cpp
index 0b1fa48bd..117d80793 100644
--- a/rosbag2_py/src/rosbag2_py/format_bag_metadata.cpp
+++ b/rosbag2_py/src/rosbag2_py/format_bag_metadata.cpp
@@ -118,7 +118,7 @@ void format_topics_with_type(
   bool verbose,
   std::stringstream & info_stream,
   int indentation_spaces,
-  const rosbag2_py::SortingMethod sort_method = rosbag2_py::SortingMethod::NAME)
+  const rosbag2_py::InfoSortingMethod sort_method = rosbag2_py::InfoSortingMethod::NAME)
 {
   if (topics.empty()) {
     info_stream << std::endl;
@@ -142,21 +142,7 @@ void format_topics_with_type(
       info_stream << std::endl;
     };
 
-  std::vector<size_t> sorted_idx(topics.size());
-  std::iota(sorted_idx.begin(), sorted_idx.end(), 0);
-  std::sort(
-    sorted_idx.begin(),
-    sorted_idx.end(),
-    [&topics, sort_method](size_t i1, size_t i2) {
-      if (sort_method == rosbag2_py::SortingMethod::TYPE) {
-        return topics[i1].topic_metadata.type < topics[i2].topic_metadata.type;
-      }
-      if (sort_method == rosbag2_py::SortingMethod::COUNT) {
-        return topics[i1].message_count < topics[i2].message_count;
-      }
-      return topics[i1].topic_metadata.name < topics[i2].topic_metadata.name;
-    }
-  );
+  std::vector<size_t> sorted_idx = rosbag2_py::generate_sorted_idx(topics, sort_method);
 
   size_t number_of_topics = topics.size();
   size_t i = 0;
@@ -186,31 +172,19 @@ void format_topics_with_type(
   }
 }
 
-struct ServiceMetadata
-{
-  std::string name;
-  std::string type;
-  std::string serialization_format;
-};
 
-struct ServiceInformation
-{
-  ServiceMetadata service_metadata;
-  size_t event_message_count = 0;
-};
-
-std::vector<std::shared_ptr<ServiceInformation>> filter_service_event_topic(
+std::vector<std::shared_ptr<rosbag2_storage::ServiceInformation>> filter_service_event_topic(
   const std::vector<rosbag2_storage::TopicInformation> & topics_with_message_count,
   size_t & total_service_event_msg_count)
 {
   total_service_event_msg_count = 0;
-  std::vector<std::shared_ptr<ServiceInformation>> service_info_list;
+  std::vector<std::shared_ptr<rosbag2_storage::ServiceInformation>> service_info_list;
 
   for (auto & topic : topics_with_message_count) {
     if (rosbag2_cpp::is_service_event_topic(
         topic.topic_metadata.name, topic.topic_metadata.type))
     {
-      auto service_info = std::make_shared<ServiceInformation>();
+      auto service_info = std::make_shared<rosbag2_storage::ServiceInformation>();
       service_info->service_metadata.name =
         rosbag2_cpp::service_event_topic_name_to_service_name(topic.topic_metadata.name);
       service_info->service_metadata.type =
@@ -227,12 +201,12 @@ std::vector<std::shared_ptr<ServiceInformation>> filter_service_event_topic(
 }
 
 void format_service_with_type(
-  const std::vector<std::shared_ptr<ServiceInformation>> & services,
+  const std::vector<std::shared_ptr<rosbag2_storage::ServiceInformation>> & services,
   const std::unordered_map<std::string, uint64_t> & messages_size,
   bool verbose,
   std::stringstream & info_stream,
   int indentation_spaces,
-  const rosbag2_py::SortingMethod sort_method = rosbag2_py::SortingMethod::NAME)
+  const rosbag2_py::InfoSortingMethod sort_method = rosbag2_py::InfoSortingMethod::NAME)
 {
   if (services.empty()) {
     info_stream << std::endl;
@@ -241,7 +215,7 @@ void format_service_with_type(
 
   auto print_service_info =
     [&info_stream, &messages_size, verbose](
-    const std::shared_ptr<ServiceInformation> & si) -> void {
+    const std::shared_ptr<rosbag2_storage::ServiceInformation> & si) -> void {
       info_stream << "Service: " << si->service_metadata.name << " | ";
       info_stream << "Type: " << si->service_metadata.type << " | ";
       info_stream << "Event Count: " << si->event_message_count << " | ";
@@ -258,21 +232,7 @@ void format_service_with_type(
       info_stream << std::endl;
     };
 
-  std::vector<size_t> sorted_idx(services.size());
-  std::iota(sorted_idx.begin(), sorted_idx.end(), 0);
-  std::sort(
-    sorted_idx.begin(),
-    sorted_idx.end(),
-    [&services, sort_method](size_t i1, size_t i2) {
-      if (sort_method == rosbag2_py::SortingMethod::TYPE) {
-        return services[i1]->service_metadata.type < services[i2]->service_metadata.type;
-      }
-      if (sort_method == rosbag2_py::SortingMethod::COUNT) {
-        return services[i1]->event_message_count < services[i2]->event_message_count;
-      }
-      return services[i1]->service_metadata.name < services[i2]->service_metadata.name;
-    }
-  );
+  std::vector<size_t> sorted_idx = rosbag2_py::generate_sorted_idx(services, sort_method);
 
   print_service_info(services[sorted_idx[0]]);
   auto number_of_services = services.size();
@@ -292,7 +252,7 @@ std::string format_bag_meta_data(
   const std::unordered_map<std::string, uint64_t> & messages_size,
   bool verbose,
   bool only_topic,
-  const SortingMethod sort_method)
+  const InfoSortingMethod sort_method)
 {
   auto start_time = metadata.starting_time.time_since_epoch();
   auto end_time = start_time + metadata.duration;
@@ -304,7 +264,7 @@ std::string format_bag_meta_data(
   }
 
   size_t total_service_event_msg_count = 0;
-  std::vector<std::shared_ptr<ServiceInformation>> service_info_list;
+  std::vector<std::shared_ptr<rosbag2_storage::ServiceInformation>> service_info_list;
   service_info_list = filter_service_event_topic(
     metadata.topics_with_message_count,
     total_service_event_msg_count);
diff --git a/rosbag2_py/src/rosbag2_py/format_bag_metadata.hpp b/rosbag2_py/src/rosbag2_py/format_bag_metadata.hpp
index de8def134..88343006a 100644
--- a/rosbag2_py/src/rosbag2_py/format_bag_metadata.hpp
+++ b/rosbag2_py/src/rosbag2_py/format_bag_metadata.hpp
@@ -18,27 +18,18 @@
 #include <string>
 #include <unordered_map>
 
+#include "info_sorting_method.hpp"
 #include "rosbag2_storage/bag_metadata.hpp"
 
 namespace rosbag2_py
 {
 
-/**
- * \brief Available sorting methods for info output.
- */
-enum class SortingMethod
-{
-  NAME,
-  TYPE,
-  COUNT,
-};
-
 std::string format_bag_meta_data(
   const rosbag2_storage::BagMetadata & metadata,
   const std::unordered_map<std::string, uint64_t> & messages_size = {},
   bool verbose = false,
   bool only_topic = false,
-  const SortingMethod sort_method = SortingMethod::NAME);
+  const InfoSortingMethod sort_method = InfoSortingMethod::NAME);
 
 }  // namespace rosbag2_py
 
diff --git a/rosbag2_py/src/rosbag2_py/format_service_info.cpp b/rosbag2_py/src/rosbag2_py/format_service_info.cpp
index 379425915..4b4f3d121 100644
--- a/rosbag2_py/src/rosbag2_py/format_service_info.cpp
+++ b/rosbag2_py/src/rosbag2_py/format_service_info.cpp
@@ -46,7 +46,8 @@ std::string
 format_service_info(
   std::vector<std::shared_ptr<rosbag2_cpp::rosbag2_service_info_t>> & service_info_list,
   const std::unordered_map<std::string, uint64_t> & messages_size,
-  bool verbose)
+  bool verbose,
+  const InfoSortingMethod sort_method)
 {
   std::stringstream info_stream;
   const std::string service_info_string = "Service information: ";
@@ -78,11 +79,13 @@ format_service_info(
       info_stream << std::endl;
     };
 
-  print_service_info(service_info_list[0]);
+  std::vector<size_t> sorted_idx = rosbag2_py::generate_sorted_idx(service_info_list, sort_method);
+
+  print_service_info(service_info_list[sorted_idx[0]]);
   auto number_of_services = service_info_list.size();
   for (size_t j = 1; j < number_of_services; ++j) {
     info_stream << std::string(indentation_spaces, ' ');
-    print_service_info(service_info_list[j]);
+    print_service_info(service_info_list[sorted_idx[j]]);
   }
 
   return info_stream.str();
diff --git a/rosbag2_py/src/rosbag2_py/format_service_info.hpp b/rosbag2_py/src/rosbag2_py/format_service_info.hpp
index 2feb1432c..58b696e08 100644
--- a/rosbag2_py/src/rosbag2_py/format_service_info.hpp
+++ b/rosbag2_py/src/rosbag2_py/format_service_info.hpp
@@ -20,6 +20,7 @@
 #include <vector>
 #include <unordered_map>
 
+#include "info_sorting_method.hpp"
 #include "rosbag2_cpp/info.hpp"
 
 namespace rosbag2_py
@@ -28,7 +29,8 @@ namespace rosbag2_py
 std::string format_service_info(
   std::vector<std::shared_ptr<rosbag2_cpp::rosbag2_service_info_t>> & service_info,
   const std::unordered_map<std::string, uint64_t> & messages_size = {},
-  bool verbose = false);
+  bool verbose = false,
+  const InfoSortingMethod sort_method = InfoSortingMethod::NAME);
 
 }  // namespace rosbag2_py
 
diff --git a/rosbag2_py/src/rosbag2_py/info_sorting_method.cpp b/rosbag2_py/src/rosbag2_py/info_sorting_method.cpp
new file mode 100644
index 000000000..cc07725e4
--- /dev/null
+++ b/rosbag2_py/src/rosbag2_py/info_sorting_method.cpp
@@ -0,0 +1,103 @@
+// Copyright 2024 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "rosbag2_storage/bag_metadata.hpp"
+
+#include "info_sorting_method.hpp"
+
+
+namespace rosbag2_py
+{
+
+InfoSortingMethod info_sorting_method_from_string(std::string str)
+{
+  std::transform(str.begin(), str.end(), str.begin(), ::tolower);
+  auto find_result = sorting_method_map.find("str");
+  if (find_result == sorting_method_map.end()) {
+    throw std::runtime_error("Enum value match for \"" + str + "\" string is not found.");
+  }
+  return find_result->second;
+}
+
+std::vector<size_t> generate_sorted_idx(
+  const std::vector<rosbag2_storage::TopicInformation> & topics,
+  const InfoSortingMethod sort_method)
+{
+  std::vector<size_t> sorted_idx(topics.size());
+  std::iota(sorted_idx.begin(), sorted_idx.end(), 0);
+  std::sort(
+    sorted_idx.begin(),
+    sorted_idx.end(),
+    [&topics, sort_method](size_t i1, size_t i2) {
+      if (sort_method == InfoSortingMethod::TYPE) {
+        return topics[i1].topic_metadata.type < topics[i2].topic_metadata.type;
+      }
+      if (sort_method == InfoSortingMethod::COUNT) {
+        return topics[i1].message_count < topics[i2].message_count;
+      }
+      return topics[i1].topic_metadata.name < topics[i2].topic_metadata.name;
+    }
+  );
+  return sorted_idx;
+}
+
+
+std::vector<size_t> generate_sorted_idx(
+  std::vector<std::shared_ptr<rosbag2_cpp::rosbag2_service_info_t>> & services,
+  const InfoSortingMethod sort_method)
+{
+  std::vector<size_t> sorted_idx(services.size());
+  std::iota(sorted_idx.begin(), sorted_idx.end(), 0);
+  std::sort(
+    sorted_idx.begin(),
+    sorted_idx.end(),
+    [&services, sort_method](size_t i1, size_t i2) {
+      if (sort_method == InfoSortingMethod::TYPE) {
+        return services[i1]->type < services[i2]->type;
+      }
+      if (sort_method == InfoSortingMethod::COUNT) {
+        const auto & count_1 = services[i1]->request_count + services[i1]->response_count;
+        const auto & count_2 = services[i2]->request_count + services[i2]->response_count;
+        return count_1 < count_2;
+      }
+      return services[i1]->name < services[i2]->name;
+    }
+  );
+  return sorted_idx;
+}
+
+
+std::vector<size_t> generate_sorted_idx(
+  const std::vector<std::shared_ptr<rosbag2_storage::ServiceInformation>> & services,
+  const InfoSortingMethod sort_method)
+{
+  std::vector<size_t> sorted_idx(services.size());
+  std::iota(sorted_idx.begin(), sorted_idx.end(), 0);
+  std::sort(
+    sorted_idx.begin(),
+    sorted_idx.end(),
+    [&services, sort_method](size_t i1, size_t i2) {
+      if (sort_method == InfoSortingMethod::TYPE) {
+        return services[i1]->service_metadata.type < services[i2]->service_metadata.type;
+      }
+      if (sort_method == InfoSortingMethod::COUNT) {
+        return services[i1]->event_message_count < services[i2]->event_message_count;
+      }
+      return services[i1]->service_metadata.name < services[i2]->service_metadata.name;
+    }
+  );
+  return sorted_idx;
+}
+
+}  // namespace rosbag2_py
diff --git a/rosbag2_py/src/rosbag2_py/info_sorting_method.hpp b/rosbag2_py/src/rosbag2_py/info_sorting_method.hpp
new file mode 100644
index 000000000..807e0116d
--- /dev/null
+++ b/rosbag2_py/src/rosbag2_py/info_sorting_method.hpp
@@ -0,0 +1,63 @@
+// Copyright 2024 Open Source Robotics Foundation, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+
+#ifndef ROSBAG2_PY__INFO_SORTING_METHOD_HPP_
+#define ROSBAG2_PY__INFO_SORTING_METHOD_HPP_
+
+#include <algorithm>
+#include <numeric>
+#include <stdexcept>
+#include <string>
+#include <unordered_map>
+#include <vector>
+#include <memory>
+
+#include "rosbag2_storage/topic_metadata.hpp"
+#include "rosbag2_storage/bag_metadata.hpp"
+#include "rosbag2_cpp/info.hpp"
+
+namespace rosbag2_py
+{
+
+/// \brief Available sorting methods for info output.
+enum class InfoSortingMethod
+{
+  NAME,
+  TYPE,
+  COUNT,
+};
+
+const std::unordered_map<std::string, InfoSortingMethod> sorting_method_map = {
+  {"name", InfoSortingMethod::NAME},
+  {"type", InfoSortingMethod::TYPE},
+  {"count", InfoSortingMethod::COUNT}};
+
+InfoSortingMethod info_sorting_method_from_string(std::string str);
+
+std::vector<size_t> generate_sorted_idx(
+  const std::vector<rosbag2_storage::TopicInformation> & topics,
+  const InfoSortingMethod sort_method = InfoSortingMethod::NAME);
+
+std::vector<size_t> generate_sorted_idx(
+  const std::vector<std::shared_ptr<rosbag2_cpp::rosbag2_service_info_t>> & services,
+  const InfoSortingMethod sort_method = InfoSortingMethod::NAME);
+
+std::vector<size_t> generate_sorted_idx(
+  const std::vector<std::shared_ptr<rosbag2_storage::ServiceInformation>> & services,
+  const InfoSortingMethod sort_method = InfoSortingMethod::NAME);
+
+}  // namespace rosbag2_py
+
+#endif  // ROSBAG2_PY__INFO_SORTING_METHOD_HPP_
diff --git a/rosbag2_storage/include/rosbag2_storage/bag_metadata.hpp b/rosbag2_storage/include/rosbag2_storage/bag_metadata.hpp
index 4bbc1cda9..865772ddb 100644
--- a/rosbag2_storage/include/rosbag2_storage/bag_metadata.hpp
+++ b/rosbag2_storage/include/rosbag2_storage/bag_metadata.hpp
@@ -32,6 +32,19 @@ struct TopicInformation
   size_t message_count;
 };
 
+struct ServiceMetadata
+{
+  std::string name;
+  std::string type;
+  std::string serialization_format;
+};
+
+struct ServiceInformation
+{
+  ServiceMetadata service_metadata;
+  size_t event_message_count = 0;
+};
+
 struct FileInformation
 {
   std::string path;