Add .nam file validation

NAM/get_dsp.cpp

@@ -1,4 +1,3 @@
-#include <fstream>
 #include <iostream>
 #include <mutex>
 #include <regex>
@@ -169,11 +168,7 @@ std::unique_ptr<DSP> get_dsp(const nlohmann::json& config, DspLoadOptions option
 std::unique_ptr<DSP> get_dsp(const std::filesystem::path config_filename, dspData& returnedConfig,
                              DspLoadOptions options)
 {
-  if (!std::filesystem::exists(config_filename))
-    throw std::runtime_error("Config file doesn't exist!\n");
-  std::ifstream i(config_filename);
-  nlohmann::json j;
-  i >> j;
+  const auto j = validate_nam_file(config_filename);
   populate_dsp_data(j, returnedConfig);
 
   /*Copy to a new dsp_config object for get_dsp below,

NAM/get_dsp.h

@@ -1,11 +1,11 @@
 #pragma once
 
-#include <fstream>
 #include <memory>
 #include <optional>
 #include <vector>
 
 #include "dsp.h"
+#include "nam_file.h"
 
 namespace nam
 {
@@ -81,6 +81,7 @@ struct DspLoadOptions
 /// \param config_filename Path to the .nam model file
 /// \param options Loading options
 /// \return Unique pointer to a DSP object
+/// \throws NamFileValidationError If the file cannot be read or does not contain a minimally valid .nam configuration
 std::unique_ptr<DSP> get_dsp(const std::filesystem::path config_filename, DspLoadOptions options = DspLoadOptions());
 
 /// \brief Get NAM from a provided configuration struct
@@ -96,6 +97,7 @@ std::unique_ptr<DSP> get_dsp(dspData& conf, DspLoadOptions options = DspLoadOpti
 /// \param returnedConfig Output parameter that will be filled with the model data
 /// \param options Loading options
 /// \return Unique pointer to a DSP object
+/// \throws NamFileValidationError If the file cannot be read or does not contain a minimally valid .nam configuration
 std::unique_ptr<DSP> get_dsp(const std::filesystem::path config_filename, dspData& returnedConfig,
                              DspLoadOptions options = DspLoadOptions());
 

NAM/nam_file.cpp

@@ -0,0 +1,41 @@
+#include "nam_file.h"
+
+#include <array>
+#include <fstream>
+#include <string>
+
+namespace nam
+{
+nlohmann::json validate_nam_file(const std::filesystem::path& filename)
+{
+  if (!std::filesystem::exists(filename))
+    throw NamFileValidationError("Could not validate .nam file [" + filename.string() + "]: file does not exist.");
+
+  std::ifstream input(filename);
+  if (!input.is_open())
+    throw NamFileValidationError("Could not validate .nam file [" + filename.string() + "]: file could not be read.");
+
+  nlohmann::json config;
+  try
+  {
+    input >> config;
+  }
+  catch (const nlohmann::json::parse_error& error)
+  {
+    throw NamFileValidationError("Could not parse .nam file [" + filename.string() + "]: " + error.what());
+  }
+
+  if (!config.is_object())
+    throw NamFileValidationError("Invalid .nam file [" + filename.string() + "]: root JSON value must be an object.");
+
+  constexpr std::array<const char*, 4> required_keys{"version", "architecture", "config", "weights"};
+  for (const auto* key : required_keys)
+  {
+    if (config.find(key) == config.end())
+      throw NamFileValidationError("Invalid .nam file [" + filename.string() + "]: missing required key \"" + key
+                                   + "\".");
+  }
+
+  return config;
+}
+} // namespace nam

NAM/nam_file.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include <filesystem>
+#include <stdexcept>
+
+#include "json.hpp"
+
+namespace nam
+{
+/// \brief Indicates that a .nam file failed validation while loading
+class NamFileValidationError : public std::runtime_error
+{
+public:
+  using std::runtime_error::runtime_error;
+};
+
+/// \brief Parse and validate a .nam file
+/// \param filename Path to the .nam file
+/// \return The parsed model configuration
+/// \throws NamFileValidationError If the file cannot be read, parsed, or does not contain the minimum required fields
+nlohmann::json validate_nam_file(const std::filesystem::path& filename);
+} // namespace nam

tools/run_tests.cpp

@@ -29,6 +29,7 @@
 #include "test/test_linear.cpp"
 #include "test/test_lstm.cpp"
 #include "test/test_lstm_realtime_safe.cpp"
+#include "test/test_nam_file.cpp"
 #include "test/test_wavenet_configurable_gating.cpp"
 #include "test/test_noncontiguous_blocks.cpp"
 #include "test/test_extensible.cpp"
@@ -297,6 +298,8 @@ int main()
 
   test_get_dsp::test_gets_input_level();
   test_get_dsp::test_gets_output_level();
+  test_get_dsp::test_empty_nam_file_throws_validation_error();
+  test_get_dsp::test_malformed_nam_file_throws_validation_error();
   test_get_dsp::test_null_input_level();
   test_get_dsp::test_null_output_level();
   test_get_dsp::test_version_patch_one_beyond_supported();
@@ -310,6 +313,10 @@ int main()
   test_get_dsp::test_get_dsp_prewarm_option_forces_constructor_reset_prewarm();
   test_get_dsp::test_get_dsp_with_returned_config_constructs_once();
 
+  test_nam_file::test_accepts_minimum_valid_file();
+  test_nam_file::test_rejects_non_object_json();
+  test_nam_file::test_rejects_missing_required_keys();
+
   // Finally, some end-to-end tests.
   test_get_dsp::test_load_and_process_nam_files();
 

tools/test/test_get_dsp.cpp

@@ -1,10 +1,13 @@
 #include <cassert>
 #include <cmath>
 #include <filesystem>
+#include <fstream>
 #include <iostream>
 #include <memory>
 #include <sstream>
+#include <stdexcept>
 #include <string>
+#include <type_traits>
 #include <vector>
 
 #include "json.hpp"
@@ -14,6 +17,8 @@
 
 namespace test_get_dsp
 {
+static_assert(std::is_base_of_v<std::runtime_error, nam::NamFileValidationError>);
+
 // Config
 const std::string basicConfigStr =
   R"({"version": "0.5.4", "metadata": {"date": {"year": 2024, "month": 10, "day": 9, "hour": 18, "minute": 44, "second": 41}, "loudness": -37.8406867980957, "gain": 0.13508800804658277, "name": "Test LSTM", "modeled_by": "Steve", "gear_type": "amp", "gear_make": "Darkglass Electronics", "gear_model": "Microtubes 900 v2", "tone_type": "clean", "input_level_dbu": 18.3, "output_level_dbu": 12.3, "training": {"settings": {"ignore_checks": false}, "data": {"latency": {"manual": null, "calibration": {"algorithm_version": 1, "delays": [-16], "safety_factor": 1, "recommended": -17, "warnings": {"matches_lookahead": false, "disagreement_too_high": false}}}, "checks": {"version": 3, "passed": true}}, "validation_esr": null}}, "architecture": "LSTM", "config": {"input_size": 1, "hidden_size": 3, "num_layers": 1}, "weights": [-0.21677088737487793, -0.6683622002601624, -0.2560940980911255, -0.3588429093360901, 0.17952610552310944, 0.19445613026618958, -0.01662646047770977, 0.5353694558143616, -0.2536540627479553, -0.5132213234901428, -0.020476307719945908, 0.08592455089092255, -0.6891753673553467, 0.3627359867095947, 0.008421811275184155, 0.3113192617893219, 0.14251480996608734, 0.07989779114723206, -0.18211324512958527, 0.7118963003158569, 0.41084015369415283, -0.6571938395500183, -0.13214066624641418, -0.2698603868484497, 0.49387243390083313, -0.3491725027561188, 0.6353667974472046, -0.5005152225494385, 0.2052856683731079, -0.4301638901233673, -0.15770092606544495, -0.7181791067123413, 0.056290093809366226, -0.49049463868141174, 0.6623441576957703, 0.09029324352741241, 0.34005245566368103, 0.16416560113430023, 0.15520110726356506, -0.4155678153038025, -0.36928507685661316, 0.3211132884025574, -0.6769840121269226, -0.1575538069009781, 0.05268515646457672, -0.4191459119319916, 0.599330484867096, 0.21518059074878693, -4.246325492858887, -3.315647840499878, -4.328850746154785, 4.496089458465576, 5.015639305114746, 3.6492037773132324, 0.14431169629096985, -0.6633821725845337, 0.11673200130462646, -0.1418764889240265, -0.4897872805595398, -0.8689419031143188, -0.06714004278182983, -0.4450395107269287, -0.02142983116209507, -0.15136894583702087, -2.775207996368408, -0.08681213855743408, 0.05702732503414154, 0.670292317867279, 0.31442636251449585, 0.30793967843055725], "sample_rate": 48000})";
@@ -50,6 +55,21 @@ nam::dspData _GetConfig(const std::string& configStr = basicConfigStr)
 namespace
 {
 
+class TemporaryNamFile
+{
+public:
+  TemporaryNamFile(const std::string& filename, const std::string& contents)
+  : path(std::filesystem::temp_directory_path() / filename)
+  {
+    std::ofstream output(path);
+    output << contents;
+  }
+
+  ~TemporaryNamFile() { std::filesystem::remove(path); }
+
+  const std::filesystem::path path;
+};
+
 constexpr const char* kConstructorResetArchitecture = "ConstructorResetPrewarmPolicyTest";
 int gConstructorResetConstructCount = 0;
 
@@ -91,6 +111,40 @@ nlohmann::json build_constructor_reset_config()
 
 } // namespace
 
+void test_empty_nam_file_throws_validation_error()
+{
+  const TemporaryNamFile file("nam_core_empty_file_test.nam", "");
+
+  try
+  {
+    nam::get_dsp(file.path);
+    assert(false);
+  }
+  catch (const nam::NamFileValidationError& error)
+  {
+    const std::string message = error.what();
+    assert(message.find(file.path.string()) != std::string::npos);
+    assert(message.find("parse") != std::string::npos);
+  }
+}
+
+void test_malformed_nam_file_throws_validation_error()
+{
+  const TemporaryNamFile file("nam_core_malformed_file_test.nam", R"({"version":)");
+
+  try
+  {
+    nam::get_dsp(file.path);
+    assert(false);
+  }
+  catch (const nam::NamFileValidationError& error)
+  {
+    const std::string message = error.what();
+    assert(message.find(file.path.string()) != std::string::npos);
+    assert(message.find("parse") != std::string::npos);
+  }
+}
+
 void test_gets_input_level()
 {
   nam::dspData config = _GetConfig();

tools/test/test_nam_file.cpp

@@ -0,0 +1,82 @@
+#include <cassert>
+#include <filesystem>
+#include <fstream>
+#include <string>
+#include <vector>
+
+#include "json.hpp"
+
+#include "NAM/nam_file.h"
+
+namespace test_nam_file
+{
+namespace
+{
+
+class TemporaryNamFile
+{
+public:
+  TemporaryNamFile(const std::string& filename, const std::string& contents)
+  : path(std::filesystem::temp_directory_path() / filename)
+  {
+    std::ofstream output(path);
+    output << contents;
+  }
+
+  ~TemporaryNamFile() { std::filesystem::remove(path); }
+
+  const std::filesystem::path path;
+};
+
+nlohmann::json minimum_valid_nam_file()
+{
+  return {{"version", "0.7.0"},
+          {"architecture", "Test"},
+          {"config", nlohmann::json::object()},
+          {"weights", nlohmann::json::array()}};
+}
+
+void assert_validation_error(const TemporaryNamFile& file, const std::string& expected_detail)
+{
+  try
+  {
+    nam::validate_nam_file(file.path);
+    assert(false);
+  }
+  catch (const nam::NamFileValidationError& error)
+  {
+    const std::string message = error.what();
+    assert(message.find(file.path.string()) != std::string::npos);
+    assert(message.find(expected_detail) != std::string::npos);
+  }
+}
+
+} // namespace
+
+void test_accepts_minimum_valid_file()
+{
+  const TemporaryNamFile file("nam_core_minimum_valid_file_test.nam", minimum_valid_nam_file().dump());
+  const auto config = nam::validate_nam_file(file.path);
+
+  assert(config.is_object());
+}
+
+void test_rejects_non_object_json()
+{
+  const TemporaryNamFile file("nam_core_non_object_file_test.nam", "[]");
+  assert_validation_error(file, "object");
+}
+
+void test_rejects_missing_required_keys()
+{
+  const std::vector<std::string> required_keys{"version", "architecture", "config", "weights"};
+  for (const auto& key : required_keys)
+  {
+    auto config = minimum_valid_nam_file();
+    config.erase(key);
+    const TemporaryNamFile file("nam_core_missing_" + key + "_test.nam", config.dump());
+    assert_validation_error(file, key);
+  }
+}
+
+} // namespace test_nam_file