ido_mysql: Automatically reconnect when necessary.

components/ido_mysql/Makefile.am

@@ -23,7 +23,7 @@ libido_mysql_la_CPPFLAGS = \
 
 libido_mysql_la_LDFLAGS = \
 	$(BOOST_LDFLAGS) \
-	$(MYSQL_LDFLAGS) \
+	$(MYSQLR_LDFLAGS) \
 	-module \
 	-no-undefined \
 	@RELEASE_INFO@ \

components/ido_mysql/mysqldbconnection.cpp

@@ -31,7 +31,7 @@ using namespace icinga;
 REGISTER_TYPE(MysqlDbConnection);
 
 MysqlDbConnection::MysqlDbConnection(const Dictionary::Ptr& serializedUpdate)
-	: DbConnection(serializedUpdate)
+	: DbConnection(serializedUpdate), m_Connected(false)
 {
 	RegisterAttribute("host", Attribute_Config, &m_Host);
 	RegisterAttribute("port", Attribute_Config, &m_Port);
@@ -47,7 +47,44 @@ MysqlDbConnection::MysqlDbConnection(const Dictionary::Ptr& serializedUpdate)
 	m_TxTimer->OnTimerExpired.connect(boost::bind(&MysqlDbConnection::TxTimerHandler, this));
 	m_TxTimer->Start();
 
-	/* TODO: move this to a timer so we can periodically check if we're still connected - and reconnect if necessary */
+	m_ReconnectTimer = boost::make_shared<Timer>();
+	m_ReconnectTimer->SetInterval(10);
+	m_ReconnectTimer->OnTimerExpired.connect(boost::bind(&MysqlDbConnection::ReconnectTimerHandler, this));
+	m_ReconnectTimer->Start();
+
+	ASSERT(mysql_thread_safe());
+}
+
+void MysqlDbConnection::Stop(void)
+{
+	boost::mutex::scoped_lock lock(m_ConnectionMutex);
+	mysql_close(&m_Connection);
+}
+
+void MysqlDbConnection::TxTimerHandler(void)
+{
+	boost::mutex::scoped_lock lock(m_ConnectionMutex);
+
+	if (!m_Connected)
+		return;
+
+	Query("COMMIT");
+	Query("BEGIN");
+}
+
+void MysqlDbConnection::ReconnectTimerHandler(void)
+{
+	boost::mutex::scoped_lock lock(m_ConnectionMutex);
+
+	if (m_Connected) {
+		/* Check if we're really still connected */
+		if (mysql_ping(&m_Connection) == 0)
+			return;
+
+		mysql_close(&m_Connection);
+		m_Connected = false;
+	}
+
 	String ihost, iuser, ipasswd, idb;
 	const char *host, *user , *passwd, *db;
 	long port;
@@ -63,15 +100,14 @@ MysqlDbConnection::MysqlDbConnection(const Dictionary::Ptr& serializedUpdate)
 	passwd = (!ipasswd.IsEmpty()) ? ipasswd.CStr() : NULL;
 	db = (!idb.IsEmpty()) ? idb.CStr() : NULL;
 
-	{
-		boost::mutex::scoped_lock lock(m_ConnectionMutex);
-
 	if (!mysql_init(&m_Connection))
 		BOOST_THROW_EXCEPTION(std::bad_alloc());
 
 	if (!mysql_real_connect(&m_Connection, host, user, passwd, db, port, NULL, 0))
 		BOOST_THROW_EXCEPTION(std::runtime_error(mysql_error(&m_Connection)));
 
+	m_Connected = true;
+
 	String instanceName = "default";
 
 	if (!m_InstanceName.IsEmpty())
@@ -107,26 +143,12 @@ MysqlDbConnection::MysqlDbConnection(const Dictionary::Ptr& serializedUpdate)
 		DbObject::Ptr dbobj = dbtype->GetOrCreateObjectByName(row->Get("name1"), row->Get("name2"));
 		SetReference(dbobj, DbReference(row->Get("object_id")));
 	}
-	}
 
 	Query("BEGIN");
 
 	UpdateAllObjects();
 }
 
-void MysqlDbConnection::Stop(void)
-{
-	boost::mutex::scoped_lock lock(m_ConnectionMutex);
-	mysql_close(&m_Connection);
-}
-
-void MysqlDbConnection::TxTimerHandler(void)
-{
-	boost::mutex::scoped_lock lock(m_ConnectionMutex);
-	Query("COMMIT");
-	Query("BEGIN");
-}
-
 Array::Ptr MysqlDbConnection::Query(const String& query)
 {
 	Log(LogDebug, "ido_mysql", "Query: " + query);
@@ -209,6 +231,10 @@ Dictionary::Ptr MysqlDbConnection::FetchRow(MYSQL_RES *result)
 void MysqlDbConnection::UpdateObject(const DbObject::Ptr& dbobj, DbUpdateType kind) {
 	boost::mutex::scoped_lock lock(m_ConnectionMutex);
 
+	/* Check if we can handle updates right now */
+	if (!m_Connected)
+		return;
+
 	DbReference dbref = GetReference(dbobj);
 
 	if (kind == DbObjectRemoved) {
@@ -234,8 +260,6 @@ void MysqlDbConnection::UpdateObject(const DbObject::Ptr& dbobj, DbUpdateType ki
 			Query(q1buf.str());
 		}
 
-		//Dictionary::Ptr cols = boost::make_shared<Dictionary>();
-
 		Dictionary::Ptr fields = dbobj->GetFields();
 
 		if (!fields)

components/ido_mysql/mysqldbconnection.h

@@ -57,8 +57,10 @@ private:
 	DbReference m_InstanceID;
 
 	boost::mutex m_ConnectionMutex;
+	bool m_Connected;
 	MYSQL m_Connection;
 
+	Timer::Ptr m_ReconnectTimer;
 	Timer::Ptr m_TxTimer;
 
 	Array::Ptr Query(const String& query);
@@ -67,6 +69,7 @@ private:
 	Dictionary::Ptr FetchRow(MYSQL_RES *result);
 
 	void TxTimerHandler(void);
+	void ReconnectTimerHandler(void);
 };
 
 }

m4/ax_lib_mysql.m4

@@ -28,6 +28,7 @@
 #
 #     AC_SUBST(MYSQL_CFLAGS)
 #     AC_SUBST(MYSQL_LDFLAGS)
+#     AC_SUBST(MYSQLR_LDFLAGS)
 #     AC_SUBST(MYSQL_VERSION)
 #
 #   And sets:
@@ -82,6 +83,7 @@ AC_DEFUN([AX_LIB_MYSQL],
         if test "$MYSQL_CONFIG" != "no"; then
             MYSQL_CFLAGS="`$MYSQL_CONFIG --cflags`"
             MYSQL_LDFLAGS="`$MYSQL_CONFIG --libs`"
+            MYSQLR_LDFLAGS="`$MYSQL_CONFIG --libs_r`"
 
             MYSQL_VERSION=`$MYSQL_CONFIG --version`
 
@@ -144,4 +146,5 @@ AC_DEFUN([AX_LIB_MYSQL],
     AC_SUBST([MYSQL_VERSION])
     AC_SUBST([MYSQL_CFLAGS])
     AC_SUBST([MYSQL_LDFLAGS])
+    AC_SUBST([MYSQLR_LDFLAGS])
 ])