From 6b2464bad413d3cb074094cc817b90e964163bd0 Mon Sep 17 00:00:00 2001
From: Jack <jackbondpreston@outlook.com>
Date: Thu, 21 Jul 2016 14:07:05 +0100
Subject: [PATCH] Fix messages occasionally not going through

Discord API will occasionally throw 502 Bad Gateway errors. Retrying
normally means this is not a problem.
---
 TriviaBot/bot/APIHelper.cpp       | 17 +++++++++++++++--
 TriviaBot/bot/http/HTTPHelper.cpp | 10 ++++++----
 TriviaBot/bot/http/HTTPHelper.hpp |  2 +-
 3 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/TriviaBot/bot/APIHelper.cpp b/TriviaBot/bot/APIHelper.cpp
index 13bc476..f4b0703 100644
--- a/TriviaBot/bot/APIHelper.cpp
+++ b/TriviaBot/bot/APIHelper.cpp
@@ -1,9 +1,13 @@
 #include "http/HTTPHelper.hpp"
 
 #include <cstdio>
+#include <thread>
+#include <chrono>
 
 #include "APIHelper.hpp"
 
+using namespace std::chrono_literals;
+
 APIHelper::APIHelper() : BASE_URL("https://discordapp.com/api"), CHANNELS_URL(BASE_URL + "/channels"),
 	JSON_CTYPE("application/json") {
 	http = new HTTPHelper();
@@ -15,6 +19,15 @@ void APIHelper::send_message(std::string channel_id, std::string message) {
 		{ "content", message }
 	};
 
-	const std::string response = http->post_request(url, JSON_CTYPE, data.dump());
-	// TODO: verify success
+	std::string response;
+	long response_code = -1;
+	response = http->post_request(url, JSON_CTYPE, data.dump(), &response_code);
+
+	int retries = 0;
+	while (response_code != 200 && retries < 2) {
+		std::this_thread::sleep_for(100ms);
+		// try 3 times. usually enough to prevent 502 bad gateway issues
+		response = http->post_request(url, JSON_CTYPE, data.dump(), &response_code);
+		retries++;
+	}
 }
\ No newline at end of file
diff --git a/TriviaBot/bot/http/HTTPHelper.cpp b/TriviaBot/bot/http/HTTPHelper.cpp
index 18b2ab6..33b6c0a 100644
--- a/TriviaBot/bot/http/HTTPHelper.cpp
+++ b/TriviaBot/bot/http/HTTPHelper.cpp
@@ -6,7 +6,7 @@ extern std::string bot_token;
 *  Warning: (Awful) C Code
 */
 
-std::string HTTPHelper::post_request(std::string url, std::string content_type, std::string data) {
+std::string HTTPHelper::post_request(std::string url, std::string content_type, std::string data, long *response_code) {
 	CURL *curl;
 	CURLcode res;
 	std::string read_buffer;
@@ -37,8 +37,10 @@ std::string HTTPHelper::post_request(std::string url, std::string content_type,
 
 		res = curl_easy_perform(curl);
 
-		if (res != CURLE_OK) {
-			return "ERROR";
+		if (res == CURLE_OK) {
+			curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, response_code);
+		} else {
+			return "";
 		}
 
 		/* always cleanup */
@@ -50,6 +52,6 @@ std::string HTTPHelper::post_request(std::string url, std::string content_type,
 }
 
 size_t HTTPHelper::write_callback(void *contents, size_t size, size_t nmemb, void *userp) {
-	((std::string *) userp)->append((char *)contents, size * nmemb);
+	((std::string *) userp)->append((char *) contents, size * nmemb);
 	return size * nmemb;
 }
\ No newline at end of file
diff --git a/TriviaBot/bot/http/HTTPHelper.hpp b/TriviaBot/bot/http/HTTPHelper.hpp
index 158e6da..3010eff 100644
--- a/TriviaBot/bot/http/HTTPHelper.hpp
+++ b/TriviaBot/bot/http/HTTPHelper.hpp
@@ -7,7 +7,7 @@
 
 class HTTPHelper {
 public:
-	std::string post_request(std::string url, std::string content_type, std::string data);
+	std::string post_request(std::string url, std::string content_type, std::string data, long *response_code);
 
 private:
 	static size_t write_callback(void *contents, size_t size, size_t nmemb, void *userp);