feat: improved human readable error messages to default logger, with …

…unit test (#921)

.vscode/settings.json

@@ -79,6 +79,7 @@
 		"coroutine": "cpp",
 		"numbers": "cpp",
 		"semaphore": "cpp",
-		"stop_token": "cpp"
+		"stop_token": "cpp",
+		"charconv": "cpp"
 	}
 }

include/dpp/restresults.h

@@ -216,6 +216,10 @@ struct DPP_EXPORT error_detail {
 	 * @brief Error reason (full message)
 	 */
 	std::string reason;
+	/**
+	 * @brief Object field index
+	 */
+	int index = 0;
 };
 
 /**
@@ -235,6 +239,10 @@ struct DPP_EXPORT error_info {
 	 * @brief Field specific error descriptions
 	 */
 	std::vector<error_detail> errors;
+	/**
+	 * @brief Human readable error message constructed from the above
+	 */
+	std::string human_readable;
 };
 
 /**

src/dpp/cluster/confirmation.cpp

@@ -82,43 +82,99 @@ error_info confirmation_callback_t::get_error() const {
 		json& errors = j["errors"];
 		for (auto obj = errors.begin(); obj != errors.end(); ++obj) {
 
-			if (obj->find("0") != obj->end()) {
+			/* Arrays in the error report are numerically indexed with a number in a string. Ugh. */
+			if (isdigit(*(obj.key().c_str()))) {
 				/* An array of error messages */
+				int array_index = std::atoll(obj.key().c_str());
 				for (auto index = obj->begin(); index != obj->end(); ++index) {
 					if (index->find("_errors") != index->end()) {
+						/* A single object where one or more fields generated an error */
 						for (auto errordetails = (*index)["_errors"].begin(); errordetails != (*index)["_errors"].end(); ++errordetails) {
 							error_detail detail;
 							detail.code = (*errordetails)["code"].get<std::string>();
 							detail.reason = (*errordetails)["message"].get<std::string>();
 							detail.object.clear();
 							detail.field = obj.key();
+							detail.index = array_index;
 							e.errors.emplace_back(detail);
 						}
 					} else {
+						/* An object where one or more fields within it generated an error, e.g. slash command */
 						for (auto fields = index->begin(); fields != index->end(); ++fields) {
-							for (auto errordetails = (*fields)["_errors"].begin(); errordetails != (*fields)["_errors"].end(); ++errordetails) {
-								error_detail detail;
-								detail.code = (*errordetails)["code"].get<std::string>();
-								detail.reason = (*errordetails)["message"].get<std::string>();
-								detail.field = fields.key();
-								detail.object = obj.key();
-								e.errors.emplace_back(detail);
+							if (fields->find("_errors") != fields->end()) {
+								for (auto errordetails = (*fields)["_errors"].begin(); errordetails != (*fields)["_errors"].end(); ++errordetails) {
+									error_detail detail;
+									detail.code = (*errordetails)["code"].get<std::string>();
+									detail.reason = (*errordetails)["message"].get<std::string>();
+									detail.field = fields.key();
+									detail.object = obj.key();
+									detail.index = array_index;
+									e.errors.emplace_back(detail);
+								}
+							} else {
+								/* An array of objects where one or more generated an error, e.g. slash command bulk registration */
+								for (auto fields2 = fields->begin(); fields2 != fields->end(); ++fields2) {
+									for (auto errordetails = (*fields2)["_errors"].begin(); errordetails != (*fields2)["_errors"].end(); ++errordetails) {
+										error_detail detail;
+										detail.code = (*errordetails)["code"].get<std::string>();
+										detail.reason = (*errordetails)["message"].get<std::string>();
+										detail.field = index.key() + "[" + fields.key() +  "]." + fields2.key();
+										detail.object = obj.key();
+										detail.index = array_index;
+										e.errors.emplace_back(detail);
+									}
+								}
 							}
 						}
 					}
 				}
 
 			} else if (obj->find("_errors") != obj->end()) {
-				/* An object of error messages */
+				/* An object of error messages (rare) */
 				e.errors.reserve((*obj)["_errors"].size());
 				for (auto errordetails = (*obj)["_errors"].begin(); errordetails != (*obj)["_errors"].end(); ++errordetails) {
 					error_detail detail;
 					detail.code = (*errordetails)["code"].get<std::string>();
 					detail.reason = (*errordetails)["message"].get<std::string>();
 					detail.object.clear();
 					detail.field = obj.key();
+					detail.index = 0;
 					e.errors.emplace_back(detail);
 				}
+			} else {
+				/* An object that has a subobject with errors */
+				for (auto index = obj->begin(); index != obj->end(); ++index) {
+					int array_index = std::atoll(index.key().c_str());
+					for (auto index2 = index->begin(); index2 != index->end(); ++index2) {
+						if (index2->find("_errors") != index2->end()) {
+							/* A single object where one or more fields generated an error */
+							for (auto errordetails = (*index2)["_errors"].begin(); errordetails != (*index2)["_errors"].end(); ++errordetails) {
+								error_detail detail;
+								detail.code = (*errordetails)["code"].get<std::string>();
+								detail.reason = (*errordetails)["message"].get<std::string>();
+								detail.object = obj.key();
+								detail.field = index2.key();
+								detail.index = array_index;
+								e.errors.emplace_back(detail);
+							}
+						}
+					}
+				}
+			}
+		}
+
+		e.human_readable = std::to_string(e.code) + ": " + e.message;
+		std::string prefix = e.errors.size() == 1 ? " " : "\n\t";
+		for (const auto& error : e.errors) {
+			if (error.object.empty()) {
+				/* A singular field with an error in an unnamed object */
+				e.human_readable += prefix + "- " + error.field + ": " + error.reason + " (" + error.code + ")";
+			} else if (isdigit(*(error.object.c_str()))) {
+				/* An unnamed array of objects where one or more generated an error, e.g. slash command bulk registration */
+				e.human_readable += prefix + "- <array>[" + error.object + "]." + error.field + ": " + error.reason + " (" + error.code + ")";
+			} else {
+				/* A named array of objects whre a field in the object has an error */
+				e.human_readable += prefix + "- " + error.object + "[" + std::to_string(error.index) + "]." + error.field + ": " + error.reason + " (" + error.code + ")";
 			}
 		}
 

src/dpp/utility.cpp

@@ -499,10 +499,10 @@ namespace dpp {
 			return [](const dpp::confirmation_callback_t& detail) {
 				if (detail.is_error()) {
 					if (detail.bot) {
+						error_info e = detail.get_error();
 						detail.bot->log(
 							dpp::ll_error, 
-							"Error " + std::to_string(detail.get_error().code) + " [" +
-							detail.get_error().message + "] on API request, returned content was: " + detail.http_info.body
+							"Error: " + e.human_readable
 						);
 					}
 				}

src/unittest/test.cpp

@@ -58,6 +58,99 @@ Markdown lol ||spoiler|| ~~strikethrough~~ `small *code* block`\n";
 	set_test(COMPARISON, u1 == u2 && u1 != u3);
 
 
+	set_test(ERRORS, false);
+
+	/* Prepare a confirmation_callback_t in error state (400) */
+	dpp::confirmation_callback_t error_test;
+	bool error_message_success = false;
+	error_test.http_info.status = 400;
+
+	error_test.http_info.body = "{\
+		\"message\": \"Invalid Form Body\",\
+		\"code\": 50035,\
+		\"errors\": {\
+			\"options\": {\
+				\"0\": {\
+					\"name\": {\
+						\"_errors\": [\
+							{\
+								\"code\": \"STRING_TYPE_REGEX\",\
+								\"message\": \"String value did not match validation regex.\"\
+							},\
+							{\
+								\"code\": \"APPLICATION_COMMAND_INVALID_NAME\",\
+								\"message\": \"Command name is invalid\"\
+							}\
+						]\
+					}\
+				}\
+			}\
+		}\
+	}";
+	error_message_success = (error_test.get_error().human_readable == "50035: Invalid Form Body\n\t- options[0].name: String value did not match validation regex. (STRING_TYPE_REGEX)\n\t- options[0].name: Command name is invalid (APPLICATION_COMMAND_INVALID_NAME)");
+
+	error_test.http_info.body = "{\
+		\"message\": \"Invalid Form Body\",\
+		\"code\": 50035,\
+		\"errors\": {\
+			\"type\": {\
+				\"_errors\": [\
+					{\
+						\"code\": \"BASE_TYPE_CHOICES\",\
+						\"message\": \"Value must be one of {4, 5, 9, 10, 11}.\"\
+					}\
+				]\
+			}\
+		}\
+	}";
+	error_message_success = (error_message_success && error_test.get_error().human_readable == "50035: Invalid Form Body - type: Value must be one of {4, 5, 9, 10, 11}. (BASE_TYPE_CHOICES)");
+
+	error_test.http_info.body = "{\
+		\"message\": \"Unknown Guild\",\
+		\"code\": 10004\
+	}";
+	error_message_success = (error_message_success && error_test.get_error().human_readable == "10004: Unknown Guild");
+
+	error_test.http_info.body = "{\
+		\"message\": \"Invalid Form Body\",\
+		\"code\": 50035,\
+		\"errors\": {\
+			\"allowed_mentions\": {\
+				\"_errors\": [\
+					{\
+						\"code\": \"MESSAGE_ALLOWED_MENTIONS_PARSE_EXCLUSIVE\",\
+						\"message\": \"parse:[\\\"users\\\"] and users: [ids...] are mutually exclusive.\"\
+					}\
+				]\
+			}\
+		}\
+	}";
+	error_message_success = (error_message_success && error_test.get_error().human_readable == "50035: Invalid Form Body - allowed_mentions: parse:[\"users\"] and users: [ids...] are mutually exclusive. (MESSAGE_ALLOWED_MENTIONS_PARSE_EXCLUSIVE)");
+
+	error_test.http_info.body = "{\
+		\"message\": \"Invalid Form Body\",\
+		\"code\": 50035,\
+		\"errors\": {\
+			\"1\": {\
+				\"options\": {\
+					\"1\": {\
+						\"description\": {\
+							\"_errors\": [\
+								{\
+									\"code\": \"BASE_TYPE_BAD_LENGTH\",\
+									\"message\": \"Must be between 1 and 100 in length.\"\
+								}\
+							]\
+						}\
+					}\
+				}\
+			}\
+		}\
+	}";
+	error_message_success = (error_message_success && error_test.get_error().human_readable == "50035: Invalid Form Body - <array>[1].options[1].description: Must be between 1 and 100 in length. (BASE_TYPE_BAD_LENGTH)");
+
+	set_test(ERRORS, error_message_success);
+
 	set_test(MD_ESC_1, false);
 	set_test(MD_ESC_2, false);
 	std::string escaped1 = dpp::utility::markdown_escape(test_to_escape);

src/unittest/test.h

@@ -144,6 +144,7 @@ DPP_TEST(CHANNELTYPES, "channel type flags", tf_online);
 DPP_TEST(FORUM_CREATION, "create a forum channel", tf_online);
 DPP_TEST(FORUM_CHANNEL_GET, "retrieve the created forum channel", tf_online);
 DPP_TEST(FORUM_CHANNEL_DELETE, "delete the created forum channel", tf_online);
+DPP_TEST(ERRORS, "Human readable error translation", tf_offline);
 
 DPP_TEST(GUILD_BAN_CREATE, "cluster::guild_ban_add ban three deleted discord accounts", tf_online);
 DPP_TEST(GUILD_BAN_GET, "cluster::guild_get_ban getting one of the banned accounts", tf_online);