Merge branch 'json_agency_comm' of ssh://github.com/ArangoDB/ArangoDB into json_agency_comm

arangod/Cluster/AgencyCallback.cpp

@@ -35,8 +35,6 @@
 
 using namespace arangodb;
 
-#include <iostream>
-
 AgencyCallback::AgencyCallback(AgencyComm& agency, 
                                std::string const& key, 
                                std::function<bool(VPackSlice const&)> const& cb,
@@ -133,7 +131,7 @@ void AgencyCallback::waitWithFailover(double timeout) {
   }
 }
 
-void AgencyCallback::waitForExecution(double maxTimeout) {
+void AgencyCallback::executeByCallbackOrTimeout(double maxTimeout) {
   auto compareBuilder = std::make_shared<VPackBuilder>();
   if (_lastData) {
     compareBuilder = _lastData;

arangod/Cluster/AgencyCallback.h

@@ -53,7 +53,7 @@ public:
   std::string const key;
   
   void refetchAndUpdate();
-  void waitForExecution(double);
+  void executeByCallbackOrTimeout(double);
   
 
 private:

arangod/Cluster/ClusterInfo.cpp

@@ -1003,10 +1003,64 @@ int ClusterInfo::createDatabaseCoordinator(std::string const& name,
   AgencyComm ac;
   AgencyCommResult res;
   
+  Mutex dbServersMutex;
+
   double const realTimeout = getTimeout(timeout);
   double const endTime = TRI_microtime() + realTimeout;
   double const interval = getPollInterval();
 
+  std::vector<ServerID> DBServers = getCurrentDBServers();
+
+  int dbServerResult = -1;
+  std::function<bool(VPackSlice const& result)> dbServerChanged =
+    [&](VPackSlice const& result) {
+    size_t numDbServers;
+    {
+      MUTEX_LOCKER(guard, dbServersMutex);
+      numDbServers = DBServers.size();
+    }
+    if (result.isObject() && result.length() == numDbServers) {
+      VPackObjectIterator dbs(result);
+      
+      std::map<std::string, AgencyCommResultEntry>::iterator it;
+      std::string tmpMsg = "";
+      bool tmpHaveError = false;
+
+      for (auto const& dbserver : dbs) {
+        VPackSlice slice = dbserver.value;
+        if (arangodb::basics::VelocyPackHelper::getBooleanValue(
+              slice, "error", false)) {
+          tmpHaveError = true;
+          tmpMsg += " DBServer:" + dbserver.key.copyString() + ":";
+          tmpMsg += arangodb::basics::VelocyPackHelper::getStringValue(
+              slice, "errorMessage", "");
+          if (slice.hasKey("errorNum")) {
+            VPackSlice errorNum = slice.get("errorNum");
+            if (errorNum.isNumber()) {
+              tmpMsg += " (errorNum=";
+              tmpMsg += basics::StringUtils::itoa(
+                  errorNum.getNumericValue<uint32_t>());
+              tmpMsg += ")";
+            }
+          }
+        }
+      }
+      if (tmpHaveError) {
+        errorMsg = "Error in creation of database:" + tmpMsg;
+        std::cout << errorMsg << std::endl;
+        dbServerResult = TRI_ERROR_CLUSTER_COULD_NOT_CREATE_DATABASE;
+        return true;
+      }
+      loadCurrentDatabases();  // update our cache
+      dbServerResult = setErrormsg(TRI_ERROR_NO_ERROR, errorMsg);
+    }
+    return true;
+  };
+  
+  auto agencyCallback = std::make_shared<AgencyCallback>(
+    ac, "Current/Databases/" + name, dbServerChanged, true, false);
+  _agencyCallbackRegistry->registerCallback(agencyCallback);
+
   {
     AgencyCommLocker locker("Plan", "WRITE");
 
@@ -1029,80 +1083,29 @@ int ClusterInfo::createDatabaseCoordinator(std::string const& name,
   // Now update our own cache of planned databases:
   loadPlannedDatabases();
   
-  // Now wait for it to appear and be complete:
-  res.clear();
-  res = ac.getValues2("Current/Version", false);
-  if (!res.successful()) {
-    return setErrormsg(TRI_ERROR_CLUSTER_COULD_NOT_READ_CURRENT_VERSION,
-                       errorMsg);
-  }
-  // HERE
-  std::vector<ServerID> DBServers = getCurrentDBServers();
   int count = 0;  // this counts, when we have to reload the DBServers
-
-  std::string where = "Current/Databases/" + name;
   while (TRI_microtime() <= endTime) {
-
+    agencyCallback->executeByCallbackOrTimeout(getReloadServerListTimeout() / interval);
-    res.clear();
+    if (dbServerResult >= 0) {
-
+      break;
-    res = ac.getValues2(where, true);
-      VPackSlice adbservers =
-        res._vpack->slice()[0]
-        .get(AgencyComm::prefixStripped()).get("Current")
-        .get("Databases").get(name);
-
-    if (res.successful() && !adbservers.isNone()) {
-
-      VPackObjectIterator dbs(adbservers);
-      
-      if (dbs.size() == DBServers.size()) {
-        std::map<std::string, AgencyCommResultEntry>::iterator it;
-        std::string tmpMsg = "";
-        bool tmpHaveError = false;
-
-        for (auto const& dbserver : dbs) {
-          VPackSlice slice = dbserver.value;
-          if (arangodb::basics::VelocyPackHelper::getBooleanValue(
-                slice, "error", false)) {
-            tmpHaveError = true;
-            tmpMsg += " DBServer:" + dbserver.key.copyString() + ":";
-            tmpMsg += arangodb::basics::VelocyPackHelper::getStringValue(
-                slice, "errorMessage", "");
-            if (slice.hasKey("errorNum")) {
-              VPackSlice errorNum = slice.get("errorNum");
-              if (errorNum.isNumber()) {
-                tmpMsg += " (errorNum=";
-                tmpMsg += basics::StringUtils::itoa(
-                    errorNum.getNumericValue<uint32_t>());
-                tmpMsg += ")";
-              }
-            }
-          }
-        }
-        if (tmpHaveError) {
-          errorMsg = "Error in creation of database:" + tmpMsg;
-          std::cout << errorMsg << std::endl;
-          return TRI_ERROR_CLUSTER_COULD_NOT_CREATE_DATABASE;
-        }
-        loadCurrentDatabases();  // update our cache
-        return setErrormsg(TRI_ERROR_NO_ERROR, errorMsg);
-      }
     }
 
-    res.clear();
-    _agencyCallbackRegistry->awaitNextChange(
-      "Current/Version", getReloadServerListTimeout() / interval);
-
     if (++count >= static_cast<int>(getReloadServerListTimeout() / interval)) {
       // We update the list of DBServers every minute in case one of them
       // was taken away since we last looked. This also helps (slightly)
       // if a new DBServer was added. However, in this case we report
       // success a bit too early, which is not too bad.
       loadCurrentDBServers();
-      DBServers = getCurrentDBServers();
+      {
+        MUTEX_LOCKER(guard, dbServersMutex);
+        DBServers = getCurrentDBServers();
+      }
       count = 0;
     }
-
+  }
+  _agencyCallbackRegistry->unregisterCallback(agencyCallback);
+  if (dbServerResult >= 0) {
+    return dbServerResult;
   }
   return setErrormsg(TRI_ERROR_CLUSTER_TIMEOUT, errorMsg);
 }
@@ -1275,9 +1278,7 @@ int ClusterInfo::createCollectionCoordinator(std::string const& databaseName,
         return true;
       }
       dbServerResult = setErrormsg(TRI_ERROR_NO_ERROR, errorMsg);
-      return true;
     }
-
     return true;
   };
 
@@ -1318,7 +1319,7 @@ int ClusterInfo::createCollectionCoordinator(std::string const& databaseName,
   loadPlannedCollections();
 
   while (TRI_microtime() <= endTime) {
-    agencyCallback->waitForExecution(interval);
+    agencyCallback->executeByCallbackOrTimeout(interval);
 
     if (dbServerResult >= 0) {
       break;
@@ -1410,7 +1411,7 @@ int ClusterInfo::dropCollectionCoordinator(std::string const& databaseName,
   loadPlannedCollections();
 
   while (TRI_microtime() <= endTime) {
-    agencyCallback->waitForExecution(interval);
+    agencyCallback->executeByCallbackOrTimeout(interval);
     if (dbServerResult >= 0) {
       break;
     }