Improvements for the ConfigManager, part 1 (ad-freiburg#1054)

`ConfigManager::addOption` now returns a reference to the created option. This makes working with this option much simpler in comparison to the previous interface, where we had to explicitly (and redundantly and error-prone) request the option by its key.

benchmark/BenchmarkExamples.cpp

@@ -13,6 +13,8 @@
 #include "util/ConfigManager/ConfigOption.h"
 #include "util/Random.h"
 
+using namespace std::string_literals;
+
 namespace ad_benchmark {
 /*
 A typical problem in benchmarking is that the result of a computation is
@@ -49,19 +51,17 @@ class ConfigOptions : public BenchmarkInterface {
   ConfigOptions() {
     ad_utility::ConfigManager& manager = getConfigManager();
 
-    manager.createConfigOption<std::string>("date", "The current date.",
-                                            &dateString_, "22.3.2023");
+    manager.addOption("date", "The current date.", &dateString_, "22.3.2023"s);
 
-    manager.createConfigOption<int>("numSigns", "The number of street signs.",
-                                    &numberOfStreetSigns_, 10);
+    manager.addOption("numSigns", "The number of street signs.",
+                      &numberOfStreetSigns_, 10);
 
-    manager.createConfigOption<std::vector<bool>>(
-        "CoinFlipTry", "The number of succesful coin flips.", &wonOnTryX_,
-        std::vector{false, false, false, false, false});
+    manager.addOption("CoinFlipTry", "The number of succesful coin flips.",
+                      &wonOnTryX_, {false, false, false, false, false});
 
-    manager.createConfigOption<float>({"Accounts", "Personal", "Steve"},
-                                      "Steves saving account balance.",
-                                      &balanceOnStevesSavingAccount_, -41.9);
+    manager.addOption({"Accounts"s, "Personal"s, "Steve"s},
+                      "Steves saving account balance.",
+                      &balanceOnStevesSavingAccount_, -41.9f);
   }
 };
 

benchmark/Usage.md

@@ -134,7 +134,7 @@ Defining the configuration options and passing values to them.
 
 ### Adding options
 
-Adding configuration options is done by adding configuration option to the private member variable `manager_`, accessible via a getter, by using the function `ConfigManager::createConfigOption`. That is best done in the constructor of your class.
+Adding configuration options is done by adding configuration option to the private member variable `manager_`, accessible via a getter, by using the function `ConfigManager::addOption`. That is best done in the constructor of your class.
 
 In our system a configuration option is described by a handful of characteristics:
 

src/util/ConfigManager/ConfigManager.cpp

@@ -9,13 +9,17 @@
 #include <absl/strings/str_cat.h>
 #include <antlr4-runtime.h>
 
+#include <algorithm>
+#include <functional>
 #include <iostream>
 #include <iterator>
 #include <ranges>
 #include <regex>
 #include <sstream>
 #include <stdexcept>
 #include <string>
+#include <type_traits>
+#include <utility>
 
 #include "util/Algorithm.h"
 #include "util/ConfigManager/ConfigExceptions.h"
@@ -30,6 +34,25 @@
 #include "util/json.h"
 
 namespace ad_utility {
+static auto configurationOptionsImpl(auto& configurationOptions) {
+  return std::views::transform(configurationOptions, [](auto& pair) {
+    // Make sure, that there is no null pointer.
+    AD_CORRECTNESS_CHECK(pair.second);
+
+    // Return a dereferenced reference.
+    return std::tie(pair.first, *pair.second);
+  });
+}
+
+// ____________________________________________________________________________
+auto ConfigManager::configurationOptions() {
+  return configurationOptionsImpl(configurationOptions_);
+}
+
+// ____________________________________________________________________________
+auto ConfigManager::configurationOptions() const {
+  return configurationOptionsImpl(configurationOptions_);
+}
 
 // ____________________________________________________________________________
 std::string ConfigManager::createJsonPointerString(
@@ -103,22 +126,8 @@ void ConfigManager::addConfigOption(
 
   // Add the configuration option.
   configurationOptions_.insert(
-      {createJsonPointerString(pathToOption), std::move(option)});
-}
-
-// ____________________________________________________________________________
-const ConfigOption& ConfigManager::getConfigurationOptionByNestedKeys(
-    const std::vector<std::string>& keys) const {
-  // If there is an config option with that described location, then this should
-  // point to the configuration option.
-  const std::string ptr{createJsonPointerString(keys)};
-
-  if (configurationOptions_.contains(ptr)) {
-    return configurationOptions_.at(ptr);
-  } else {
-    throw NoConfigOptionFoundException(vectorOfKeysForJsonToString(keys),
-                                       printConfigurationDoc(true));
-  }
+      {createJsonPointerString(pathToOption),
+       std::make_unique<ConfigOption>(std::move(option))});
 }
 
 // ____________________________________________________________________________
@@ -217,7 +226,7 @@ void ConfigManager::parseConfig(const nlohmann::json& j) {
   an exception, if a configuration option was given a value of the wrong type,
   or if it HAD to be set, but wasn't.
   */
-  for (auto& [key, option] : configurationOptions_) {
+  for (auto&& [key, option] : configurationOptions()) {
     // Set the option, if possible, with the pointer to the position of the
     // current configuration in json.
     if (const nlohmann::json::json_pointer configurationOptionJsonPosition{key};
@@ -229,8 +238,8 @@ void ConfigManager::parseConfig(const nlohmann::json& j) {
 
     /*
     If the option hasn't set the variable, that it's internal variable pointer
-    points to, that means, it doesn't have a default value, and needs to be set
-    by the user at runtime, but wasn't.
+    points to, that means, it doesn't have a default value, and needs to be
+    set by the user at runtime, but wasn't.
     */
     if (!option.wasSet()) {
       throw ConfigOptionWasntSetException(key);
@@ -258,7 +267,7 @@ std::string ConfigManager::printConfigurationDoc(
   - The default value of the configuration option.
   - An example value, of the correct type.
   */
-  for (const auto& [path, option] : configurationOptions_) {
+  for (const auto& [path, option] : configurationOptions()) {
     // Pointer to the position of this option in
     // `configuratioOptionsVisualization`.
     const nlohmann::json::json_pointer jsonOptionPointer{path};
@@ -281,13 +290,13 @@ std::string ConfigManager::printConfigurationDoc(
 
   // List the configuration options themselves.
   const std::string& listOfConfigurationOptions = ad_utility::lazyStrJoin(
-      std::views::transform(configurationOptions_,
+      std::views::transform(configurationOptions(),
                             [](const auto& pair) {
                               // Add the location of the option and the option
                               // itself.
                               return absl::StrCat(
-                                  "Location : ", pair.first, "\n",
-                                  static_cast<std::string>(pair.second));
+                                  "Location : ", std::get<0>(pair), "\n",
+                                  static_cast<std::string>(std::get<1>(pair)));
                             }),
       "\n\n");
 
@@ -320,8 +329,8 @@ std::string
 ConfigManager::getListOfNotChangedConfigOptionsWithDefaultValuesAsString()
     const {
   // For only looking at the configuration options in our map.
-  auto onlyConfigurationOptionsView = std::views::transform(
-      configurationOptions_, [](const auto& pair) { return pair.second; });
+  auto onlyConfigurationOptionsView =
+      std::views::values(configurationOptions());
 
   // Returns true, if the `ConfigOption` has a default value and wasn't set at
   // runtime.