From dc0ba2984e9d6ed9af0cc62d4f2f5535206c24b2 Mon Sep 17 00:00:00 2001
From: King_DuckZ <king_duckz@gmx.com>
Date: Tue, 20 Oct 2020 22:18:44 +0200
Subject: [PATCH] Retry when server responds 503 too.

That's "Service Unavailable", it's
probably a temporary failure.
---
 src/oro/api_nap_exception.cpp |  2 +-
 src/timer_oro_api.cpp         | 23 ++++++++++++++++-------
 2 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/src/oro/api_nap_exception.cpp b/src/oro/api_nap_exception.cpp
index 3f2bbd8..9d9b384 100644
--- a/src/oro/api_nap_exception.cpp
+++ b/src/oro/api_nap_exception.cpp
@@ -36,7 +36,7 @@ std::size_t append_to_char_arary (std::string_view in, char* out, std::size_t of
 
 ServerError::ServerError (const nap::HttpResponse& resp) :
 	std::runtime_error(
-		std::string("Server replied: ") + std::to_string(resp.code) + " (" +
+		std::string("Server replied: ") + std::to_string(resp.code) + " (HTTP " +
 			std::string(resp.http_ver) + ", \"" + std::string(resp.code_desc) +
 			"\")"
 	),
diff --git a/src/timer_oro_api.cpp b/src/timer_oro_api.cpp
index 78453c0..7ec1332 100644
--- a/src/timer_oro_api.cpp
+++ b/src/timer_oro_api.cpp
@@ -22,6 +22,7 @@
 #	include "lzma.hpp"
 #endif
 #include "base64.hpp"
+#include "magic_enum.hpp"
 #if defined(OROTOOL_WITH_RESTCCPP)
 #	include <restc-cpp/error.h>
 #elif defined(OROTOOL_WITH_NAP)
@@ -70,7 +71,7 @@ inline TimerOroApi<Op>::TimerOroApi (
 
 template<oro::DBOperation Op>
 inline void TimerOroApi<Op>::fetch_data (oro::SourceFormat store_mode) {
-	int status_code = 200;
+	bool schedule_retry = false;
 	try {
 		auto results = invoke_api_func<Op>(oro_api(), store_mode);
 		set_next_timer(results.header);
@@ -96,8 +97,9 @@ inline void TimerOroApi<Op>::fetch_data (oro::SourceFormat store_mode) {
 	}
 #if defined(OROTOOL_WITH_RESTCCPP)
 	catch (const restc_cpp::RequestFailedWithErrorException& err) {
-		status_code = err.http_response.status_code;
+		const int status_code = err.http_response.status_code;
 		if (429 == err.http_response.status_code) {
+			schedule_retry = true;
 			//server received too many requests, give up for now
 		}
 		else {
@@ -106,10 +108,17 @@ inline void TimerOroApi<Op>::fetch_data (oro::SourceFormat store_mode) {
 	}
 #elif defined(OROTOOL_WITH_NAP)
 	catch (const oro::ServerError& err) {
-		status_code = err.error_code();
-		if (429 == status_code) {
-		}
-		else {
+		const int status_code = err.error_code();
+		switch (status_code) {
+		case 503:
+			std::cerr << "Server returned 503 during request for " <<
+				magic_enum::enum_name(Op) << '\n';
+			schedule_retry = true;
+			break;
+		case 429:
+			schedule_retry = true;
+			break;
+		default:
 			throw;
 		}
 	}
@@ -134,7 +143,7 @@ inline void TimerOroApi<Op>::fetch_data (oro::SourceFormat store_mode) {
 #endif
 
 	m_retries_left = error_retries();
-	if (429 == status_code) {
+	if (schedule_retry) {
 		oro::Header head;
 		head.date.ts = std::chrono::time_point_cast<oro::timestamp_t::duration>(std::chrono::system_clock::now());
 		head.rate_limit = 1;