Files
the-biergarten-app/tooling/pipeline/src/json_handling/json_loader.cc
2026-06-23 00:45:32 -04:00

237 lines
7.6 KiB
C++

/**
* @file json_handling/json_loader.cc
* @brief Parses curated location JSON input into strongly typed Location
* records with strict field validation and descriptive error reporting.
*/
#include "json_handling/json_loader.h"
#include <boost/json.hpp>
#include <format>
#include <fstream>
#include <iostream>
#include <sstream>
#include <stdexcept>
#include <string>
#include <string_view>
#include <unordered_map>
#include <utility>
#include "services/logging/logger.h"
static std::string ReadRequiredString(const boost::json::object& object,
const char* key) {
const boost::json::value* value = object.if_contains(key);
if (value == nullptr || !value->is_string()) {
throw std::runtime_error(
std::format("Missing or invalid string field: {}", key));
}
const std::string_view text = value->as_string();
return std::string(text);
}
static double ReadRequiredNumber(const boost::json::object& object,
const char* key) {
const boost::json::value* value = object.if_contains(key);
if (value == nullptr || !value->is_number()) {
throw std::runtime_error(
std::format("Missing or invalid numeric field: {}", key));
}
return value->to_number<double>();
}
static std::vector<std::string> ReadRequiredStringArray(
const boost::json::object& object, const char* key) {
const boost::json::value* value = object.if_contains(key);
if (value == nullptr || !value->is_array()) {
throw std::runtime_error(
std::format("Missing or invalid string array field: {}", key));
}
const auto& array = value->as_array();
std::vector<std::string> items;
items.reserve(array.size());
for (const auto& item : array) {
if (!item.is_string()) {
throw std::runtime_error(
std::format("Missing or invalid string array field: {}", key));
}
items.emplace_back(item.as_string());
}
return items;
}
namespace {
boost::json::value ParseJsonFile(const std::filesystem::path& filepath,
const char* what) {
std::ifstream input(filepath);
if (!input.is_open()) {
throw std::runtime_error(
std::format("Failed to open {} file: {}", what, filepath.string()));
}
std::stringstream buffer;
buffer << input.rdbuf();
boost::system::error_code error;
boost::json::value root = boost::json::parse(buffer.str(), error);
if (error) {
throw std::runtime_error(
std::format("Failed to parse {} JSON: {}", what, error.message()));
}
return root;
}
/**
* @brief Returns the first element of a string array field, falling back to
* `fallback_key` if `key` is missing/empty (some source entries only have a
* "localized" form and no "romanized" form).
*/
std::string ReadFirstOfStringArray(const boost::json::object& object,
const char* key, const char* fallback_key) {
for (const char* candidate_key : {key, fallback_key}) {
const boost::json::value* value = object.if_contains(candidate_key);
if (value == nullptr || !value->is_array()) {
continue;
}
const auto& array = value->as_array();
if (!array.empty() && array.front().is_string()) {
return std::string(array.front().as_string());
}
}
throw std::runtime_error(
std::format("Missing or invalid string array field: {}", key));
}
} // namespace
std::vector<Location> JsonLoader::LoadLocations(
const std::filesystem::path& filepath) {
const boost::json::value root = ParseJsonFile(filepath, "locations");
if (!root.is_array()) {
throw std::runtime_error(
"Invalid locations JSON: root element must be an array");
}
std::vector<Location> locations;
const auto& items = root.as_array();
locations.reserve(items.size());
for (const auto& item : items) {
if (!item.is_object()) {
throw std::runtime_error(
"Invalid locations JSON: each entry must be an object");
}
const auto& object = item.as_object();
locations.push_back(Location{
.city = ReadRequiredString(object, "city"),
.state_province = ReadRequiredString(object, "state_province"),
.iso3166_2 = ReadRequiredString(object, "iso3166_2"),
.country = ReadRequiredString(object, "country"),
.iso3166_1 = ReadRequiredString(object, "iso3166_1"),
.local_languages = ReadRequiredStringArray(object, "local_languages"),
.latitude = ReadRequiredNumber(object, "latitude"),
.longitude = ReadRequiredNumber(object, "longitude"),
});
}
return locations;
}
std::vector<UserPersona> JsonLoader::LoadPersonas(
const std::filesystem::path& filepath) {
const boost::json::value root = ParseJsonFile(filepath, "personas");
if (!root.is_array()) {
throw std::runtime_error(
"Invalid personas JSON: root element must be an array");
}
std::vector<UserPersona> personas;
const auto& items = root.as_array();
personas.reserve(items.size());
for (const auto& item : items) {
if (!item.is_object()) {
throw std::runtime_error(
"Invalid personas JSON: each entry must be an object");
}
const auto& object = item.as_object();
personas.push_back(UserPersona{
.name = ReadRequiredString(object, "name"),
.description = ReadRequiredString(object, "description"),
.style_affinities = ReadRequiredStringArray(object, "style_affinities"),
});
}
return personas;
}
NamesByCountry JsonLoader::LoadNamesByCountry(
const std::filesystem::path& forenames_filepath,
const std::filesystem::path& surnames_filepath) {
const boost::json::value forenames_root =
ParseJsonFile(forenames_filepath, "forenames-by-country");
const boost::json::value surnames_root =
ParseJsonFile(surnames_filepath, "surnames-by-country");
if (!forenames_root.is_object() || !surnames_root.is_object()) {
throw std::runtime_error(
"Invalid names-by-country JSON: root element must be an object "
"keyed by ISO 3166-1 country code");
}
std::unordered_map<std::string, std::vector<ForenameEntry>>
forenames_by_country;
for (const auto& [country_code, regions] : forenames_root.as_object()) {
if (!regions.is_array()) {
continue;
}
std::vector<ForenameEntry> entries;
for (const auto& region : regions.as_array()) {
if (!region.is_object()) {
continue;
}
const boost::json::value* names = region.as_object().if_contains("names");
if (names == nullptr || !names->is_array()) {
continue;
}
for (const auto& name_value : names->as_array()) {
if (!name_value.is_object()) {
continue;
}
const auto& name_object = name_value.as_object();
entries.push_back(ForenameEntry{
.name =
ReadFirstOfStringArray(name_object, "romanized", "localized"),
.gender = ReadRequiredString(name_object, "gender"),
});
}
}
forenames_by_country.emplace(country_code, std::move(entries));
}
std::unordered_map<std::string, std::vector<std::string>> surnames_by_country;
for (const auto& [country_code, name_entries] : surnames_root.as_object()) {
if (!name_entries.is_array()) {
continue;
}
std::vector<std::string> surnames;
for (const auto& name_value : name_entries.as_array()) {
if (!name_value.is_object()) {
continue;
}
surnames.push_back(ReadFirstOfStringArray(name_value.as_object(),
"romanized", "localized"));
}
surnames_by_country.emplace(country_code, std::move(surnames));
}
return NamesByCountry(std::move(forenames_by_country),
std::move(surnames_by_country));
}