Pymem json

.github/workflows/ci.yml

@@ -53,22 +53,11 @@ jobs:
         if: runner.os == 'Linux'
         run: |
           sudo apt update
-          sudo apt install libeigen3-dev qtdeclarative5-dev qt5-qmake libqglviewer-dev-qt5 libsuitesparse-dev lcov libspdlog-dev
-
-      - name: Install cereal on Ubuntu
-        if: runner.os == 'Linux'
-        run: |
-          cd /tmp
-          wget https://github.com/USCiLab/cereal/archive/refs/tags/v1.3.2.tar.gz
-          tar xaf v1.3.2.tar.gz
-          cd cereal-1.3.2
-          mkdir build; cd build
-          cmake -DJUST_INSTALL_CEREAL:=On ..
-          sudo make install
+          sudo apt install libeigen3-dev qtdeclarative5-dev qt5-qmake libqglviewer-dev-qt5 libsuitesparse-dev lcov libspdlog-dev nlohmann-json3-dev
 
       - name: Install dependencies on macOS
         if: runner.os == 'macOS'
-        run: brew install cmake eigen coreutils
+        run: brew install cmake eigen coreutils nlohmann-json
 
       - name: Configure ccache for macOS
         if: runner.os == 'macOS'

CMakeLists.txt

@@ -421,16 +421,16 @@ set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${g2o_CXX_FLAGS}")
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${g2o_C_FLAGS}")
 
 find_package(Eigen3 3.3 REQUIRED)
-find_package(cereal)
+find_package(nlohmann_json 3.2.0)
 
 # Generate config.h
 set(G2O_OPENGL_FOUND ${OPENGL_FOUND})
 set(G2O_HAVE_CHOLMOD ${CHOLMOD_FOUND})
 set(G2O_HAVE_CSPARSE ${G2O_USE_CSPARSE})
-if (TARGET cereal::cereal)
-  set(G2O_HAVE_CEREAL 1)
+if (TARGET nlohmann_json::nlohmann_json)
+  set(G2O_HAVE_JSON 1)
 else()
-  set(G2O_HAVE_CEREAL 0)
+  set(G2O_HAVE_JSON 0)
 endif()
 set(G2O_SHARED_LIBS ${BUILD_SHARED_LIBS})
 set(G2O_LGPL_SHARED_LIBS ${BUILD_LGPL_SHARED_LIBS})

README.md

@@ -100,9 +100,9 @@ following packages.
 
 -   spdlog <https://github.com/gabime/spdlog>
 -   suitesparse <http://faculty.cse.tamu.edu/davis/suitesparse.html>
--   cereal <https://uscilab.github.io/cereal/index.html>
 -   Qt5 <http://qt-project.org>
 -   libQGLViewer <http://www.libqglviewer.com>
+-   JSON for Modern C++ <https://github.com/nlohmann/json>
 
 On Ubuntu / Debian these dependencies are resolved by installing the
 following packages.

config.h.in

@@ -7,7 +7,7 @@
 #cmakedefine G2O_SHARED_LIBS 1
 #cmakedefine G2O_LGPL_SHARED_LIBS 1
 
-#cmakedefine G2O_HAVE_CEREAL 1
+#cmakedefine G2O_HAVE_JSON 1
 
 // available sparse matrix libraries
 #cmakedefine G2O_HAVE_CHOLMOD 1

g2o/core/CMakeLists.txt

@@ -44,7 +44,6 @@ io/io_format.cpp
 io/io_binary.cpp io/io_binary.h
 io/io_json.cpp io/io_json.h
 io/io_g2o.cpp io/io_g2o.h
-io/io_xml.cpp io/io_xml.h
 )
 
 target_include_directories(core PUBLIC
@@ -58,8 +57,8 @@ set_target_properties(core PROPERTIES
   SOVERSION ${G2O_LIB_SOVERSION})
 target_link_libraries(core PUBLIC stuff Eigen3::Eigen)
 target_link_libraries(core PUBLIC g2o_ceres_ad)
-if (TARGET cereal::cereal)
-target_link_libraries(core PUBLIC cereal::cereal)
+if (TARGET nlohmann_json::nlohmann_json)
+  target_link_libraries(core PRIVATE nlohmann_json::nlohmann_json)
 endif()
 target_compile_features(core PUBLIC cxx_std_17)
 

g2o/core/abstract_graph.cpp

@@ -32,7 +32,6 @@
 #include "g2o/core/io/io_binary.h"
 #include "g2o/core/io/io_format.h"
 #include "g2o/core/io/io_json.h"
-#include "g2o/core/io/io_xml.h"
 #include "g2o/stuff/logger.h"
 #include "io/io_g2o.h"
 
@@ -54,8 +53,6 @@ std::unique_ptr<g2o::IoInterface> allocate(g2o::io::Format format) {
       return std::make_unique<g2o::IoBinary>();
     case g2o::io::Format::kJson:
       return std::make_unique<g2o::IoJson>();
-    case g2o::io::Format::kXML:
-      return std::make_unique<g2o::IoXml>();
   }
   G2O_CRITICAL("Failed to create graph IO interface for format {}",
                g2o::io::to_string(format));

g2o/core/io/io_binary.cpp

@@ -30,26 +30,35 @@
 
 #include "g2o/config.h"
 #include "g2o/core/abstract_graph.h"
-
-#ifdef G2O_HAVE_CEREAL
-#include <cereal/archives/portable_binary.hpp>
-#include <cereal/cereal.hpp>
-
-#include "io_wrapper_cereal.h"  // IWYU pragma: keep
-#else
 #include "g2o/stuff/logger.h"
-#endif  // HAVE CEREAL
+
+#ifdef G2O_HAVE_JSON
+#include "io_wrapper_json.h"
+#endif  // HAVE_JSON
 
 namespace g2o {
 
-#ifdef G2O_HAVE_CEREAL
+#ifdef G2O_HAVE_JSON
 
 std::optional<AbstractGraph> IoBinary::load(std::istream& input) {
-  return io::load<cereal::PortableBinaryInputArchive>(input, "BINARY");
+  try {
+    return json::fromJson(nlohmann::json::from_cbor(input));
+  } catch (const std::exception& e) {
+    G2O_ERROR("Exception while loading: {}", e.what());
+  }
+  return std::nullopt;
 }
 
 bool IoBinary::save(std::ostream& output, const AbstractGraph& graph) {
-  return io::save<cereal::PortableBinaryOutputArchive>(output, graph, "BINARY");
+  try {
+    std::vector<std::uint8_t> binary =
+        nlohmann::json::to_cbor(json::toJson(graph));
+    output.write(reinterpret_cast<char*>(binary.data()), binary.size());
+    return output.good();
+  } catch (const std::exception& e) {
+    G2O_ERROR("Exception while saving: {}", e.what());
+  }
+  return false;
 }
 
 #else

g2o/core/io/io_format.cpp

@@ -41,16 +41,13 @@ std::string_view to_string(g2o::io::Format format) {
       return "Binary";
     case g2o::io::Format::kJson:
       return "JSON";
-    case g2o::io::Format::kXML:
-      return "XML";
   }
   return "";
 }
 
 std::optional<Format> formatForFileExtension(std::string_view extension) {
   if (extension == "g2o" || extension == "G2O") return Format::kG2O;
   if (extension == "json" || extension == "JSON") return Format::kJson;
-  if (extension == "xml" || extension == "XML") return Format::kXML;
   if (extension == "bin" || extension == "BIN") return Format::kBinary;
   return std::nullopt;
 }
@@ -66,7 +63,6 @@ std::vector<FileFilter> getFileFilter(bool open) {
   std::vector<FileFilter> result;
   result.emplace_back("g2o Ascii files (*.g2o)", Format::kG2O);
   result.emplace_back("g2o Json files (*.json)", Format::kJson);
-  result.emplace_back("g2o XML files (*.xml)", Format::kXML);
   result.emplace_back("g2o BIN files (*.bin)", Format::kBinary);
   if (open) {
     result.emplace_back("All Files (*)", Format::kUndefined);

g2o/core/io/io_format.h

@@ -40,7 +40,6 @@ enum class G2O_CORE_API Format {
   kG2O = 0,
   kBinary = 1,
   kJson = 2,
-  kXML = 3
 };
 
 G2O_CORE_API std::string_view to_string(g2o::io::Format format);

g2o/core/io/io_json.cpp

@@ -26,30 +26,42 @@
 
 #include "io_json.h"
 
+#include <exception>
 #include <optional>
 
 #include "g2o/config.h"
 #include "g2o/core/abstract_graph.h"
+#include "g2o/stuff/logger.h"
 
-#ifdef G2O_HAVE_CEREAL
-#include <cereal/archives/json.hpp>
-#include <cereal/cereal.hpp>
+#ifdef G2O_HAVE_JSON
+#include <nlohmann/json.hpp>
 
-#include "io_wrapper_cereal.h"  // IWYU pragma: keep
-#else
-#include "g2o/stuff/logger.h"
-#endif  // HAVE CEREAL
+#include "io_wrapper_json.h"
+#endif  // HAVE_JSON
 
 namespace g2o {
 
-#ifdef G2O_HAVE_CEREAL
+#ifdef G2O_HAVE_JSON
 
 std::optional<AbstractGraph> IoJson::load(std::istream& input) {
-  return io::load<cereal::JSONInputArchive>(input, "JSON");
+  try {
+    nlohmann::json json;
+    input >> json;
+    return json::fromJson(json);
+  } catch (const std::exception& e) {
+    G2O_ERROR("Exception while saving: {}", e.what());
+  }
+  return std::nullopt;
 }
 
 bool IoJson::save(std::ostream& output, const AbstractGraph& graph) {
-  return io::save<cereal::JSONOutputArchive>(output, graph, "JSON");
+  try {
+    output << json::toJson(graph);
+  } catch (const std::exception& e) {
+    G2O_ERROR("Exception while saving: {}", e.what());
+    return false;
+  }
+  return true;
 }
 
 #else