Removed cluster seed nodes, added 'join.contact-point', changed joining phase, added singleton cluster mode plus misc other changes.

Signed-off-by: Jonas Bonér <jonas@jonasboner.com>

akka-cluster/src/main/resources/reference.conf

@@ -8,9 +8,19 @@
 akka {
 
   cluster {
+<<<<<<< HEAD
     # node to join - the full URI defined by a string on the form of "akka://system@hostname:port"
     #     leave as empty string if the node should be a singleton cluster
     node-to-join = ""
+=======
+    join {
+      # contact point on the form of "hostname:port" of a node to try to join
+      #     leave as empty string if the node should be a singleton cluster
+      contact-point = ""
+      timeout = 30s
+      max-time-to-retry = 30s
+    }
+>>>>>>> Removed cluster seed nodes, added 'join.contact-point', changed joining phase, added singleton cluster mode plus misc other changes.
 
     gossip {
       initialDelay = 5s

akka-cluster/src/main/scala/akka/cluster/Gossiper.scala

@@ -314,6 +314,16 @@ case class Gossiper(system: ActorSystemImpl, remote: RemoteActorRefProvider) {
       log.info("Node [{}] - Sending [{}] to [{}] through connection [{}]", remoteAddress, command, member.address, connection)
       connection ! command
     }
+
+    contactPoint match {
+      case None ⇒ log.info("Booting up in singleton cluster mode")
+      case Some(member) ⇒
+        log.info("Trying to join contact point node defined in the configuration [{}]", member)
+        setUpConnectionTo(member) match {
+          case None             ⇒ log.error("Could not set up connection to join contact point node defined in the configuration [{}]", member)
+          case Some(connection) ⇒ tryJoinContactPoint(connection, deadline)
+        }
+    }
   }
 
   /**

akka-cluster/src/test/scala/akka/cluster/ClusterConfigSpec.scala

@@ -25,7 +25,11 @@ class ClusterConfigSpec extends AkkaSpec(
       import settings._
       FailureDetectorThreshold must be(8)
       FailureDetectorMaxSampleSize must be(1000)
-      NodeToJoin must be(None)
+
+      JoinContactPoint must be(None)
+      JoinTimeout must be(30 seconds)
+      JoinMaxTimeToRetry must be(30 seconds)
+
       GossipInitialDelay must be(5 seconds)
       GossipFrequency must be(1 second)
     }

akka-docs/cluster/cluster.rst

@@ -74,12 +74,13 @@ each node hosting some part of the application. Cluster membership and
 partitioning of the application are decoupled. A node could be a member of a
 cluster without hosting any actors.
 
-Single-node Cluster
--------------------
+
+Singleton Cluster
+-----------------
 
 If a node does not have a preconfigured contact point to join in the Akka
-configuration, then it is considered a single-node cluster and will
-automatically transition from ``joining`` to ``up``. Single-node clusters
+configuration, then it is considered a singleton cluster (single node cluster)
+and will automatically transition from ``joining`` to ``up``. Singleton clusters
 can later explicitly send a ``Join`` message to another node to form a N-node
 cluster. It is also possible to link multiple N-node clusters by ``joining`` them.