Add recursive callback to manage auth and db select

lib/redis/redisconnection.cpp

@@ -30,7 +30,7 @@
 using namespace icinga;
 
 RedisConnection::RedisConnection(const String host, const int port, const String path, const String password, const int db) :
-		m_Host(host), m_Port(port), m_Path(path), m_Password(password), m_DbIndex(db), m_Context(NULL)
+		m_Host(host), m_Port(port), m_Path(path), m_Password(password), m_DbIndex(db), m_Context(NULL), m_Connected(false)
 {
 	m_RedisConnectionWorkQueue.SetName("RedisConnection");
 }
@@ -70,12 +70,58 @@ void RedisConnection::HandleRW()
 	}
 }
 
+
+void RedisConnection::RedisInitialCallback(redisAsyncContext *c, void *r, void *p)
+{
+	auto *state = (ConnectionState *) p;
+	if (r != nullptr) {
+		redisReply *rep = (redisReply *) r;
+		if (rep->type == REDIS_REPLY_ERROR) {
+			Log(LogCritical, "RedisConnection")
+				<< "Failed to connect to Redis: " << rep->str;
+			state->conn->m_Connected = false;
+			return;
+		}
+	}
+
+	if (state->state != Starting && (!r || c->err)) {
+		Log(LogCritical, "RedisConnection") << c->errstr;
+		state->conn->m_Connected = false;
+		return;
+	}
+
+	if (state->state == Starting) {
+		state->state = Auth;
+		if (!state->conn->m_Password.IsEmpty()) {
+			boost::mutex::scoped_lock lock(state->conn->m_CMutex);
+			redisAsyncCommand(c, &RedisInitialCallback, p, "AUTH %s", state->conn->m_Password.CStr());
+			return;
+		}
+	}
+	if (state->state == Auth)
+	{
+		state->state = DBSelect;
+		if (state->conn->m_DbIndex != 0) {
+			boost::mutex::scoped_lock lock(state->conn->m_CMutex);
+			redisAsyncCommand(c, &RedisInitialCallback, p, "SELECT %d", state->conn->m_DbIndex);
+			return;
+		}
+	}
+	if (state->state == DBSelect)
+		state->conn->m_Connected = true;
+}
+bool RedisConnection::IsConnected() {
+	return m_Connected;
+}
+
+
 void RedisConnection::Connect()
 {
 	if (m_Context)
 		return;
 
 	Log(LogInformation, "RedisWriter", "Trying to connect to redis server Async");
+	{
 		boost::mutex::scoped_lock lock(m_CMutex);
 
 		if (m_Path.IsEmpty())
@@ -98,17 +144,10 @@ void RedisConnection::Connect()
 		}
 
 		redisAsyncSetDisconnectCallback(m_Context, &DisconnectCallback);
-
-	/* TODO: This currently does not work properly:
-	 * In case of error the connection is broken, yet the Context is not set to faulty. May be a bug with hiredis.
-     * Error case: Password does not match, or even: "Client sent AUTH, but no password is set" which also results in an error.
-     */
-	if (!m_Password.IsEmpty()) {
-		ExecuteQuery({"AUTH", m_Password});
 	}
 
-	if (m_DbIndex != 0)
-		ExecuteQuery({"SELECT", Convert::ToString(m_DbIndex)});
+	m_State = ConnectionState{Starting, this};
+	RedisInitialCallback(m_Context, nullptr, (void*)&m_State);
 }
 
 void RedisConnection::Disconnect()
@@ -129,11 +168,6 @@ void RedisConnection::DisconnectCallback(const redisAsyncContext *c, int status)
 
 }
 
-bool RedisConnection::IsConnected()
-{
-	return (REDIS_CONNECTED & m_Context->c.flags) == REDIS_CONNECTED;
-}
-
 void RedisConnection::ExecuteQuery(const std::vector<String>& query, redisCallbackFn *fn, void *privdata)
 {
 	m_RedisConnectionWorkQueue.Enqueue(std::bind(&RedisConnection::SendMessageInternal, this, query, fn, privdata));

lib/redis/redisconnection.hpp

@@ -31,6 +31,20 @@ namespace icinga
  *
  * @ingroup redis
  */
+
+	enum conn_state{
+		Starting,
+		Auth,
+		DBSelect,
+		Done,
+	};
+
+	class RedisConnection;
+	struct ConnectionState {
+		conn_state state;
+		RedisConnection *conn;
+	};
+
 	class RedisConnection final : public Object
 	{
 	public:
@@ -62,6 +76,9 @@ namespace icinga
 
 		static void DisconnectCallback(const redisAsyncContext *c, int status);
 
+		static void RedisInitialCallback(redisAsyncContext *c, void *r, void *p);
+
+
 		WorkQueue m_RedisConnectionWorkQueue{100000};
 		Timer::Ptr m_EventLoop;
 
@@ -72,14 +89,18 @@ namespace icinga
 		int m_Port;
 		String m_Password;
 		int m_DbIndex;
+		bool m_Connected;
 
 		boost::mutex m_CMutex;
+		ConnectionState m_State;
+
 	};
 
 	struct redis_error : virtual std::exception, virtual boost::exception { };
 
 	struct errinfo_redis_query_;
 	typedef boost::error_info<struct errinfo_redis_query_, std::string> errinfo_redis_query;
+
 }
 
 #endif //REDISCONNECTION_H

lib/redis/rediswriter.cpp

@@ -104,11 +104,13 @@ void RedisWriter::TryToReconnect()
 {
 	AssertOnWorkQueue();
 
-	if (m_ConfigDumpDone && m_Rcon->IsConnected())
+	if (m_ConfigDumpDone)
 		return;
-	else if (!m_Rcon->IsConnected())
+	else
 		m_Rcon->Start();
 
+	if (!m_Rcon->IsConnected())
+		return;
 	UpdateSubscriptions();
 
 	if (m_ConfigDumpInProgress || m_ConfigDumpDone)
@@ -135,8 +137,11 @@ void RedisWriter::UpdateSubscriptions()
 
 	Log(LogInformation, "RedisWriter", "Updating Redis subscriptions");
 
-	m_Subscriptions.clear();
-
+	if (!m_Rcon->IsConnected()) {
+		Log(LogCritical, "DEBUG, Redis")
+				<< "NO CONNECT CHIEF";
+		return;
+	}
 	long long cursor = 0;
 
 	String keyPrefix = "icinga:subscription:";
@@ -349,7 +354,7 @@ redisReply* RedisWriter::RedisGet(const std::vector<String>& query) {
 
 	boost::mutex::scoped_lock lock(wait->mtx);
 	while (!wait->ready) {
-		wait->cv.timed_wait(lock, boost::posix_time::milliseconds(long(15 * 1000)));
+		wait->cv.wait(lock);
 		if (!wait->ready)
 			wait->ready = true;
 	}