From d6b429dc9facf3f5e2e04aac2f9fc2312511c1a9 Mon Sep 17 00:00:00 2001
From: Eugene Kim <ek@harmony.one>
Date: Tue, 8 Oct 2019 13:49:00 -0700
Subject: [PATCH] Process messages after node is fully initialized

This obviates polling logic for receiver being nil.
---
 node/node.go         | 29 +++++++++++++++--------------
 node/node_handler.go | 13 -------------
 2 files changed, 15 insertions(+), 27 deletions(-)

diff --git a/node/node.go b/node/node.go
index 90d86dbbc..b2666fc47 100644
--- a/node/node.go
+++ b/node/node.go
@@ -413,6 +413,21 @@ func (node *Node) getTransactionsForNewBlock(
 
 // StartServer starts a server and process the requests by a handler.
 func (node *Node) StartServer() {
+	for i := 0; i < RxWorkers; i++ {
+		go node.handleIncomingMessages()
+	}
+
+	// start the goroutine to receive client message
+	// client messages are sent by clients, like txgen, wallet
+	go node.ReceiveClientGroupMessage()
+
+	// start the goroutine to receive group message
+	go node.ReceiveGroupMessage()
+
+	// start the goroutine to receive global message, used for cross-shard TX
+	// FIXME (leo): we use beacon client topic as the global topic for now
+	go node.ReceiveGlobalMessage()
+
 	select {}
 }
 
@@ -528,20 +543,6 @@ func New(host p2p.Host, consensusObj *consensus.Consensus, chainDBFactory shardc
 		Msg("Genesis block hash")
 
 	node.incomingMessages = make(chan incomingMessage, RxQueueSize)
-	for i := 0; i < RxWorkers; i++ {
-		go node.handleIncomingMessages()
-	}
-
-	// start the goroutine to receive client message
-	// client messages are sent by clients, like txgen, wallet
-	go node.ReceiveClientGroupMessage()
-
-	// start the goroutine to receive group message
-	go node.ReceiveGroupMessage()
-
-	// start the goroutine to receive global message, used for cross-shard TX
-	// FIXME (leo): we use beacon client topic as the global topic for now
-	go node.ReceiveGlobalMessage()
 
 	// Setup initial state of syncing.
 	node.peerRegistrationRecord = make(map[string]*syncConfig)
diff --git a/node/node_handler.go b/node/node_handler.go
index 79834019a..956c6a045 100644
--- a/node/node_handler.go
+++ b/node/node_handler.go
@@ -41,10 +41,6 @@ func (node *Node) ReceiveGlobalMessage() {
 	ctx := context.Background()
 	for {
 		// TODO ek – infinite loop; add shutdown/cleanup logic
-		if node.globalGroupReceiver == nil {
-			time.Sleep(100 * time.Millisecond)
-			continue
-		}
 		msg, sender, err := node.globalGroupReceiver.Receive(ctx)
 		if err != nil {
 			utils.Logger().Warn().Err(err).
@@ -65,10 +61,6 @@ func (node *Node) ReceiveGroupMessage() {
 	ctx := context.Background()
 	// TODO ek – infinite loop; add shutdown/cleanup logic
 	for {
-		if node.shardGroupReceiver == nil {
-			time.Sleep(100 * time.Millisecond)
-			continue
-		}
 		msg, sender, err := node.shardGroupReceiver.Receive(ctx)
 		if err != nil {
 			utils.Logger().Warn().Err(err).
@@ -89,11 +81,6 @@ func (node *Node) ReceiveClientGroupMessage() {
 	ctx := context.Background()
 	// TODO ek – infinite loop; add shutdown/cleanup logic
 	for {
-		if node.clientReceiver == nil {
-			// check less frequent on client messages
-			time.Sleep(100 * time.Millisecond)
-			continue
-		}
 		msg, sender, err := node.clientReceiver.Receive(ctx)
 		if err != nil {
 			utils.Logger().Warn().Err(err).