introduce a simple batcher, simplify mapresponsing

Signed-off-by: Kristoffer Dalby <[email protected]>

hscontrol/poll.go

@@ -201,12 +201,12 @@ func (m *mapSession) serve() {
 
  // true means changed, false means removed
  var changed map[types.NodeID]bool
- var messages []string
  var derp bool
 
  // Set full to true to immediatly send a full mapresponse
  full := true
  prev := time.Now()
+ lastMessage := ""
 
  // Loop through updates and continuously send them to the
  // client.
@@ -234,13 +234,13 @@ func (m *mapSession) serve() {
  m.tracef("Sending DERPUpdate MapResponse")
  data, err = m.mapper.DERPMapResponse(m.req, m.node, m.h.DERPMap)
  } else {
- m.tracef(fmt.Sprintf("Sending Changed MapResponse: %v", messages))
- data, err = m.mapper.PeerChangedResponse(m.req, m.node, changed, m.h.ACLPolicy, messages...)
+ m.tracef(fmt.Sprintf("Sending Changed MapResponse: %v", lastMessage))
+ data, err = m.mapper.PeerChangedResponse(m.req, m.node, changed, m.h.ACLPolicy, lastMessage)
  }
 
  // reset
  changed = nil
- messages = nil
+ lastMessage = ""
  full = false
  derp = false
  prev = time.Now()
@@ -297,16 +297,19 @@ func (m *mapSession) serve() {
  if changed == nil {
  changed = make(map[types.NodeID]bool)
  }
+
  for _, nodeID := range update.ChangeNodes {
  changed[nodeID] = true
  }
- messages = append(messages, update.Message)
+
+ lastMessage = update.Message
  case types.StatePeerChangedPatch:
  // TODO(kradalby):
  case types.StatePeerRemoved:
  if changed == nil {
  changed = make(map[types.NodeID]bool)
  }
+
  for _, nodeID := range update.Removed {
  changed[nodeID] = false
  }
@@ -315,7 +318,8 @@ func (m *mapSession) serve() {
  if changed == nil {
  changed = make(map[types.NodeID]bool)
  }
- messages = append(messages, update.Message)
+
+ lastMessage = update.Message
  case types.StateDERPUpdated:
  derp = true
  }