Remove unused code

1. History is not very useful in its current form because we do not
which nodes the gossip happens by memberlist.
2. memberlist has enough debug info so this is not required.

api.go

@@ -72,9 +72,6 @@ type Gossiper interface {
 	// GetNodes returns a list of the connection addresses
 	GetNodes() []string
 
-	// GetGossipHistory returns the gossip records for last 20 sessions.
-	GetGossipHistory() []*types.GossipSessionInfo
-
 	// UpdateCluster updates gossip with latest peer nodes Id-Ip mapping
 	UpdateCluster(map[types.NodeId]string)
 

proto/gossip.go

@@ -1,7 +1,6 @@
 package proto
 
 import (
-	"container/list"
 	"errors"
 	"fmt"
 	"math/rand"
@@ -17,75 +16,6 @@ import (
 	"github.com/libopenstorage/gossip/types"
 )
 
-type GossipHistory struct {
-	// front is the latest, back is the last
-	nodes  *list.List
-	lock   sync.Mutex
-	maxLen uint8
-}
-
-func NewGossipSessionInfo(node string,
-	dir types.GossipDirection) *types.GossipSessionInfo {
-	gs := new(types.GossipSessionInfo)
-	gs.Node = node
-	gs.Dir = dir
-	gs.Ts = time.Now()
-	gs.Err = ""
-	return gs
-}
-
-func NewGossipHistory(maxLen uint8) *GossipHistory {
-	s := new(GossipHistory)
-	s.nodes = list.New()
-	s.nodes.Init()
-	s.maxLen = maxLen
-	return s
-}
-
-func (s *GossipHistory) AddLatest(gs *types.GossipSessionInfo) {
-	s.lock.Lock()
-	defer s.lock.Unlock()
-	if uint8(s.nodes.Len()) == s.maxLen {
-		s.nodes.Remove(s.nodes.Back())
-	}
-	s.nodes.PushFront(gs)
-}
-
-func (s *GossipHistory) GetAllRecords() []*types.GossipSessionInfo {
-	s.lock.Lock()
-	defer s.lock.Unlock()
-	records := make([]*types.GossipSessionInfo, s.nodes.Len(), s.nodes.Len())
-	i := 0
-	for element := s.nodes.Front(); element != nil; element = element.Next() {
-		r, ok := element.Value.(*types.GossipSessionInfo)
-		if !ok || r == nil {
-			log.Error("gossip: Failed to convert element")
-			continue
-		}
-		records[i] = &types.GossipSessionInfo{Node: r.Node,
-			Ts: r.Ts, Dir: r.Dir, Err: r.Err}
-		i++
-	}
-	return records
-}
-
-func (s *GossipHistory) LogRecords() {
-	s.lock.Lock()
-	defer s.lock.Unlock()
-	status := make([]string, 2)
-	status[types.GD_ME_TO_PEER] = "ME_TO_PEER"
-	status[types.GD_PEER_TO_ME] = "PEER_TO_ME"
-
-	for element := s.nodes.Front(); element != nil; element = element.Next() {
-		r, ok := element.Value.(*types.GossipSessionInfo)
-		if !ok || r == nil {
-			continue
-		}
-		log.Infof("Node: %v LastTs: %v Dir: %v Error: %v",
-			r.Node, r.Ts, status[r.Dir], r.Err)
-	}
-}
-
 type GossipNode struct {
 	Id types.NodeId
 	Ip string
@@ -229,10 +159,6 @@ func (g *GossiperImpl) GossipInterval() time.Duration {
 	return g.gossipInterval
 }
 
-func (g *GossiperImpl) GetGossipHistory() []*types.GossipSessionInfo {
-	return g.history.GetAllRecords()
-}
-
 func (g *GossiperImpl) GetNodes() []string {
 	nodes := g.mlist.Members()
 	nodeList := make([]string, len(nodes))

proto/gossip_delegates.go

@@ -21,7 +21,6 @@ type GossipDelegate struct {
 	// last gossip time
 	lastGossipTsLock sync.Mutex
 	lastGossipTs     time.Time
-	history          *GossipHistory
 	// channel to receive state change events
 	stateEvent chan types.StateEvent
 	// current State object
@@ -50,7 +49,6 @@ func (gd *GossipDelegate) InitGossipDelegate(
 		clusterId,
 	)
 	gd.quorumTimeout = quorumTimeout
-	gd.history = NewGossipHistory(20)
 }
 
 func (gd *GossipDelegate) InitCurrentState(clusterSize int) {
@@ -143,22 +141,13 @@ func (gd *GossipDelegate) GetBroadcasts(overhead, limit int) [][]byte {
 func (gd *GossipDelegate) LocalState(join bool) []byte {
 	gd.updateSelfTs()
 
-	// We don't know which node we are talking to.
-	gs := NewGossipSessionInfo("", types.GD_ME_TO_PEER)
-	gs.Op = types.LocalPush
-
 	// We send our local state of nodeMap
 	// The receiver will decide which nodes to merge and which to ignore
-
 	byteLocalState, err := gd.GetLocalStateInBytes()
 	if err != nil {
-		gs.Err = fmt.Sprintf("gossip: Error in LocalState. Unable to unmarshal: %v", err.Error())
-		logrus.Infof(gs.Err)
 		byteLocalState = []byte{}
 	}
-	gs.Err = ""
 	gd.updateGossipTs()
-	gd.history.AddLatest(gs)
 	return byteLocalState
 }
 
@@ -174,18 +163,14 @@ func (gd *GossipDelegate) MergeRemoteState(buf []byte, join bool) {
 	}
 	gd.updateSelfTs()
 
-	gs := NewGossipSessionInfo("", types.GD_PEER_TO_ME)
 	err := gd.convertFromBytes(buf, &remoteState)
 	if err != nil {
-		gs.Err = fmt.Sprintf("gossip: Error in unmarshalling peer's local data. Error : %v", err.Error())
-		logrus.Infof(gs.Err)
+		logrus.Infof("gossip: Error in unmarshalling peer's local data. "+
+			"Error : %v", err.Error())
 	}
 
 	gd.Update(remoteState)
-	gs.Op = types.MergeRemote
-	gs.Err = ""
 	gd.updateGossipTs()
-	gd.history.AddLatest(gs)
 	return
 }
 
@@ -198,20 +183,14 @@ func (gd *GossipDelegate) NotifyJoin(node *memberlist.Node) {
 		return
 	}
 
-	gs := NewGossipSessionInfo(nodeName, types.GD_PEER_TO_ME)
-	gs.Op = types.NotifyJoin
 	gd.updateGossipTs()
 
 	// NotifyAlive should remove a node from memberlist if the
 	// gossip version mismatches.
 	// Nevertheless we are doing an extra check here.
-	err := gd.gossipChecks(node)
-	if err != nil {
-		gs.Err = err.Error()
+	if err := gd.gossipChecks(node); err != nil {
 		gd.RemoveNode(types.NodeId(nodeName))
 	}
-
-	gd.history.AddLatest(gs)
 }
 
 // NotifyLeave is invoked when a node is detected to have left.
@@ -229,11 +208,7 @@ func (gd *GossipDelegate) NotifyLeave(node *memberlist.Node) {
 		gd.triggerStateEvent(types.NODE_LEAVE)
 	}
 
-	gs := NewGossipSessionInfo(nodeName, types.GD_PEER_TO_ME)
-	gs.Err = ""
-	gs.Op = types.NotifyLeave
 	gd.updateGossipTs()
-	gd.history.AddLatest(gs)
 	return
 }
 
@@ -266,15 +241,10 @@ func (gd *GossipDelegate) NotifyAlive(node *memberlist.Node) error {
 		return nil
 	}
 
-	gs := NewGossipSessionInfo(nodeName, types.GD_PEER_TO_ME)
-	gs.Op = types.NotifyAlive
-	gs.Err = ""
 	gd.updateGossipTs()
 
 	err := gd.gossipChecks(node)
 	if err != nil {
-		gs.Err = err.Error()
-		gd.history.AddLatest(gs)
 		gd.RemoveNode(types.NodeId(nodeName))
 		// Do not add this node to the memberlist.
 		// Returning a non-nil err value
@@ -287,7 +257,6 @@ func (gd *GossipDelegate) NotifyAlive(node *memberlist.Node) error {
 		gd.triggerStateEvent(types.NODE_ALIVE)
 	} // else if err != nil -> A new node sending us data. We do not add node unless it is added
 	// in our local map externally
-	gd.history.AddLatest(gs)
 	return nil
 }
 

proto/gossip_test.go

@@ -38,56 +38,6 @@ func NewGossiperImplWithClusterId(ip string, selfNodeId types.NodeId, knownIps [
 	return newGossiperImpl(ip, selfNodeId, knownIps, version, clusterId)
 }
 
-func TestGossiperHistory(t *testing.T) {
-	var maxLen uint8 = 5
-	h := NewGossipHistory(maxLen)
-
-	for i := 0; i < 2*int(maxLen); i++ {
-		h.AddLatest(NewGossipSessionInfo(strconv.Itoa(i),
-			types.GD_ME_TO_PEER))
-		if i < 5 {
-			records := h.GetAllRecords()
-			if len(records) != i+1 {
-				t.Error("Length of returned records don't match, r:", len(records),
-					" expected: ", h.nodes.Len())
-			}
-		}
-	}
-
-	if h.nodes.Len() != int(maxLen) {
-		t.Error("Len mismatch h: ", h.nodes.Len(), " expected: ", maxLen)
-	}
-
-	records := h.GetAllRecords()
-	if len(records) != h.nodes.Len() {
-		t.Error("Length of returned records don't match, r:", len(records),
-			" expected: ", h.nodes.Len())
-	}
-
-	var p *types.GossipSessionInfo = nil
-	for _, c := range records {
-		if p != nil {
-			pId, ok3 := strconv.Atoi(p.Node)
-			cId, ok4 := strconv.Atoi(c.Node)
-
-			if ok3 != nil || ok4 != nil {
-				t.Error("Failed to get elements: p: ", p, " c: ", c)
-				continue
-			}
-
-			if pId < cId {
-				t.Error("Data maintained in wrong order ", p, " c: ", c)
-			}
-
-			if p.Ts.Before(c.Ts) {
-				t.Error("Data maintained in wrong order ", p, " c: ", c)
-			}
-		}
-		p = c
-	}
-
-}
-
 func TestGossiperStartStopGetNode(t *testing.T) {
 	printTestInfo()
 

types/types.go

@@ -61,14 +61,6 @@ const (
 	NotifyLeave GossipOp = "Notify Leave"
 )
 
-type GossipSessionInfo struct {
-	Node string
-	Ts   time.Time
-	Dir  GossipDirection
-	Err  string
-	Op   GossipOp
-}
-
 type NodeMetaInfo struct {
 	ClusterId     string
 	GossipVersion string