This commit allows new servers ina supercluster to be informed of accounts with active leafnode connections.

This is needed to put those accounts into interest only mode for inbound gateway connections. Also added code
to make sure we were doing proper account tracking and would track the global account as well, which used to
be excluded.

Fixes #977

Signed-off-by: Derek Collison <derek@nats.io>

test/leafnode_test.go

@@ -1,4 +1,4 @@
-// Copyright 2019 The NATS Authors
+// Copyright 2019-2020 The NATS Authors
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
@@ -702,7 +702,10 @@ func createClusterEx(t *testing.T, doAccounts bool, clusterName string, numServe
 	}
 
 	bindGlobal := func(s *server.Server) {
-		ngs, _ := s.LookupAccount("NGS")
+		ngs, err := s.LookupAccount("NGS")
+		if err != nil {
+			return
+		}
 		// Bind global to service import
 		gacc, _ := s.LookupAccount("$G")
 		gacc.AddServiceImport(ngs, "ngs.usage", "ngs.usage.$G")
@@ -940,6 +943,42 @@ func TestLeafNodeWithRouteAndGateway(t *testing.T) {
 	checkLmsg(t, matches[0], "bar", "", "2", "OK")
 }
 
+// This will test that we propagate interest only mode after a leafnode
+// has been established and a new server joins a remote cluster.
+func TestLeafNodeWithGatewaysAndStaggeredStart(t *testing.T) {
+	ca := createClusterWithName(t, "A", 1)
+	defer shutdownCluster(ca)
+
+	// Create the leafnode on a server in cluster A.
+	opts := ca.opts[0]
+	lc := createLeafConn(t, opts.LeafNode.Host, opts.LeafNode.Port)
+	defer lc.Close()
+
+	leafSend, leafExpect := setupLeaf(t, lc, 3)
+	leafSend("PING\r\n")
+	leafExpect(pongRe)
+
+	// Now setup the cluster B.
+	cb := createClusterWithName(t, "B", 1, ca)
+	defer shutdownCluster(cb)
+
+	// Create client on a server in cluster B
+	opts = cb.opts[0]
+	c := createClientConn(t, opts.Host, opts.Port)
+	defer c.Close()
+
+	send, expect := setupConn(t, c)
+	send("PING\r\n")
+	expect(pongRe)
+
+	// Make sure we see interest graph propagation on the leaf node
+	// connection. This is required since leaf nodes only send data
+	// in the presence of interest.
+	send("SUB foo 1\r\nPING\r\n")
+	expect(pongRe)
+	leafExpect(lsubRe)
+}
+
 func TestLeafNodeLocalizedDQ(t *testing.T) {
 	s, opts := runLeafServer()
 	defer s.Shutdown()