Stabilize 2

PROJ1/findSuccessor/findSuccessor.go

@@ -0,0 +1,28 @@
+package findSuccessor
+
+import (
+	"math"
+
+	nodeDefs "../utils/node_defs"
+)
+
+//FindSuccessor ... This function is used to find successor of node with ID targetID
+func FindSuccessor(sponsoringNode *nodeDefs.Node, targetID int64, totalNodes int) (successor *nodeDefs.Node) {
+	if targetID > sponsoringNode.ChannelId && targetID <= sponsoringNode.Successor.ChannelId {
+		successor = sponsoringNode.Successor
+	} else {
+		precedingNode := findClosestPrecedingNode(sponsoringNode, targetID, totalNodes)
+		successor = FindSuccessor(precedingNode, targetID, totalNodes)
+	}
+	return successor
+}
+
+func findClosestPrecedingNode(sponsoringNode *nodeDefs.Node, targetID int64, totalNodes int) (precedingNode *nodeDefs.Node) {
+
+	for i := int(math.Log2(float64(totalNodes))); i >= 0; i-- {
+		if sponsoringNode.FingerTable[int64(i)].ChannelId > sponsoringNode.ChannelId && sponsoringNode.FingerTable[int64(i)].ChannelId < targetID {
+			precedingNode = sponsoringNode.FingerTable[int64(i)]
+		}
+	}
+	return
+}

PROJ1/main.go

@@ -198,6 +198,28 @@ func generate_channel_id() (rand_num int64){
 }
 
 
+
+//Stabilize ...
+func Stabilize(n *node.Node) {
+	x := n.Successor
+	var message = msg.Message {Do:"find-ring-predecessor", TargetId: x, RespondTo: n.ChannelId}
+    string_message, err := json.Marshal(message)
+    check_error(err)
+	SendDataToNetwork(n.ChannelId, string(string_message))
+
+	x = GetDataFromBucket(n.ChannelId)
+
+	if x > n.ChannelId && x < n.Successor {
+		n.Successor = x
+	}
+	log.Println(n.Successor, n.ChannelId)
+
+	message = msg.Message {Do: "ring-notify", RespondTo: n.ChannelId}
+	string_message, err = json.Marshal(message)
+    check_error(err)
+}
+
+
 /*
 Initializes the network with nodes with random identifiers.
 Creates nodes with random identifiers and adds them to the network map.
@@ -534,6 +556,17 @@ func net_node(channel_id int64){
 						sponsoring_node_id := message.SponsoringNode
 						Join_ring(sponsoring_node_id, &node_obj)
 						ring_nodes.Store(channel_id, &node_obj)
+
+						var message = msg.Message {Do:"stabilize"}
+
+						string_message, err := json.Marshal(message)
+						check_error(err)
+						//Tell sponsoring_node_id to find the successor of the node_obj
+						SendDataToNetwork(node_obj.ChannelId, string(string_message))
+						//Wait to hear back what the successor is
+
+
+
 					}else{
 						log.Printf("\nNode %d is already in the ring; cannot join-ring\n", channel_id)
 					}
@@ -570,6 +603,8 @@ func net_node(channel_id int64){
 				}else if message.Do == "set-successor" {
 					//Set the successor as the target id
 					node_obj.Successor = message.TargetId
+				} else if message.Do == "stabilize" {
+					Stabilize(&node_obj)
 				}
 
 				if execute_fix_fingers == true {
@@ -726,6 +761,7 @@ func coordinator(prog_args []string){
 			check_error(err)
 			// Give a random node instructions 
 			network[channel_id] <- string(modified_inst)
+			time.Sleep(5 * time.Second)
 	}
 
 	//Every 7 seconds, tell someone to fix their fingers

PROJ1/utils/message_defs/message_defs.go

@@ -1,6 +1,5 @@
 package message_defs
 
-
 /*
 This struct defines the json messages for the
 CHORD protocol.