added static helper methods for cluster state

arangod/Aql/Collection.cpp

@@ -227,8 +227,10 @@ void Collection::fillIndexes () const {
   if (! indexes.empty()) {
     return;
   }
+  
+  auto const role = triagens::arango::ServerState::instance()->getRole();
 
-  if (triagens::arango::ServerState::instance()->isCoordinator()) {
+  if (triagens::arango::ServerState::instance()->isCoordinator(role)) {
     fillIndexesCoordinator();
     return;
   }
@@ -236,7 +238,7 @@ void Collection::fillIndexes () const {
   // must have a collection  
   TRI_ASSERT(collection != nullptr);
 
-  if (triagens::arango::ServerState::instance()->isDBServer() && 
+  if (triagens::arango::ServerState::instance()->isDBServer(role) && 
       documentCollection()->_info._planId > 0) {
     fillIndexesDBServer();
     return;

arangod/Aql/ExecutionEngine.cpp

@@ -901,8 +901,9 @@ ExecutionEngine* ExecutionEngine::instanciateFromPlan (QueryRegistry* queryRegis
                                                        Query* query,
                                                        ExecutionPlan* plan,
                                                        bool planRegisters) {
-  bool const isCoordinator = triagens::arango::ServerState::instance()->isCoordinator();
-  bool const isDBServer    = triagens::arango::ServerState::instance()->isDBServer();
+  auto role = triagens::arango::ServerState::instance()->getRole();
+  bool const isCoordinator = triagens::arango::ServerState::instance()->isCoordinator(role);
+  bool const isDBServer    = triagens::arango::ServerState::instance()->isDBServer(role);
 
   ExecutionEngine* engine = nullptr;
 

arangod/Cluster/HeartbeatThread.cpp

@@ -491,15 +491,18 @@ bool HeartbeatThread::handlePlanChangeCoordinator (uint64_t currentPlanVersion,
       ++it;
     }
 
+    // get the list of databases that we know about locally
     TRI_voc_tick_t* localIds = TRI_GetIdsCoordinatorDatabaseServer(_server);
 
     if (localIds != nullptr) {
       TRI_voc_tick_t* p = localIds;
 
+      // now check which of the local databases are also in the plan
       while (*p != 0) {
         std::vector<TRI_voc_tick_t>::const_iterator r = std::find(ids.begin(), ids.end(), *p);
 
         if (r == ids.end()) {
+          // local database not found in the plan...
           TRI_DropByIdCoordinatorDatabaseServer(_server, *p, false);
         }
 

arangod/Cluster/ServerState.cpp

@@ -102,7 +102,7 @@ ServerState* ServerState::instance () {
 /// @brief get the string representation of a role
 ////////////////////////////////////////////////////////////////////////////////
 
-std::string ServerState::roleToString (RoleEnum role) {
+std::string ServerState::roleToString (ServerState::RoleEnum role) {
   switch (role) {
     case ROLE_UNDEFINED:
       return "UNDEFINED";
@@ -238,7 +238,15 @@ bool ServerState::isCoordinator () {
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-/// @brief check whether the server is a DB server (primary or secondory)
+/// @brief check whether the server is a coordinator
+////////////////////////////////////////////////////////////////////////////////
+
+bool ServerState::isCoordinator (ServerState::RoleEnum role) {
+  return (role == ServerState::ROLE_COORDINATOR);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check whether the server is a DB server (primary or secondary)
 /// running in cluster mode.
 ////////////////////////////////////////////////////////////////////////////////
 
@@ -249,6 +257,16 @@ bool ServerState::isDBServer () {
           role == ServerState::ROLE_SECONDARY);
 }
 
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check whether the server is a DB server (primary or secondary)
+/// running in cluster mode.
+////////////////////////////////////////////////////////////////////////////////
+
+bool ServerState::isDBServer (ServerState::RoleEnum role) {
+  return (role == ServerState::ROLE_PRIMARY ||
+          role == ServerState::ROLE_SECONDARY);
+}
+
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief check whether the server is running in a cluster
 ////////////////////////////////////////////////////////////////////////////////
@@ -316,7 +334,7 @@ ServerState::RoleEnum ServerState::getRole () {
 /// @brief set the server role
 ////////////////////////////////////////////////////////////////////////////////
 
-void ServerState::setRole (RoleEnum role) {
+void ServerState::setRole (ServerState::RoleEnum role) {
   storeRole(role);
 }
 

arangod/Cluster/ServerState.h

@@ -188,12 +188,25 @@ namespace triagens {
         bool isCoordinator ();
 
 ////////////////////////////////////////////////////////////////////////////////
-/// @brief check whether the server is a DB server (primary or secondory)
+/// @brief check whether the server is a coordinator
+////////////////////////////////////////////////////////////////////////////////
+
+        static bool isCoordinator (RoleEnum);
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check whether the server is a DB server (primary or secondary)
 /// running in cluster mode.
 ////////////////////////////////////////////////////////////////////////////////
 
         bool isDBServer ();
 
+////////////////////////////////////////////////////////////////////////////////
+/// @brief check whether the server is a DB server (primary or secondary)
+/// running in cluster mode.
+////////////////////////////////////////////////////////////////////////////////
+
+        static bool isDBServer (RoleEnum);
+
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief check whether the server is running in a cluster
 ////////////////////////////////////////////////////////////////////////////////

arangod/RestServer/ArangoServer.cpp

@@ -986,7 +986,9 @@ int ArangoServer::startupServer () {
   // for a cluster coordinator, the users are loaded at a later stage;
   // the kickstarter will trigger a bootstrap process
   //
-  if (role != ServerState::ROLE_COORDINATOR && role != ServerState::ROLE_PRIMARY && role != ServerState::ROLE_SECONDARY) {
+  if (role != ServerState::ROLE_COORDINATOR && 
+      role != ServerState::ROLE_PRIMARY && 
+      role != ServerState::ROLE_SECONDARY) {
 
     // if the authentication info could not be loaded, but authentication is turned on,
     // then we refuse to start