From bb560a1f443e2101527947f8b937e70ca83e6553 Mon Sep 17 00:00:00 2001
From: Madhu Venugopal <madhu@docker.com>
Date: Tue, 31 Jan 2017 09:13:08 -0800
Subject: [PATCH] Generating node discovery events to the drivers from
 networkdb

With the introduction of networkdb, the node discovery events were not
sent to the drivers. This commit generates the node discovery events and
sents it to the drivers interested in it.

Signed-off-by: Madhu Venugopal <madhu@docker.com>
---
 libnetwork/agent.go                    | 28 ++++++++++++++++++++++++++
 libnetwork/controller.go               |  6 ++++++
 libnetwork/networkdb/event_delegate.go | 19 ++++++++++++++++-
 libnetwork/networkdb/watch.go          | 14 ++++++++++++-
 4 files changed, 65 insertions(+), 2 deletions(-)

diff --git a/libnetwork/agent.go b/libnetwork/agent.go
index 540aa79cf8..6a03fa8f58 100644
--- a/libnetwork/agent.go
+++ b/libnetwork/agent.go
@@ -3,6 +3,7 @@ package libnetwork
 //go:generate protoc -I.:Godeps/_workspace/src/github.com/gogo/protobuf  --gogo_out=import_path=github.com/docker/libnetwork,Mgogoproto/gogo.proto=github.com/gogo/protobuf/gogoproto:. agent.proto
 
 import (
+	"encoding/json"
 	"fmt"
 	"net"
 	"os"
@@ -285,6 +286,7 @@ func (c *controller) agentInit(listenAddr, bindAddrOrInterface, advertiseAddr st
 	}
 
 	ch, cancel := nDB.Watch("endpoint_table", "", "")
+	nodeCh, cancel := nDB.Watch(networkdb.NodeTable, "", "")
 
 	c.Lock()
 	c.agent = &agent{
@@ -297,6 +299,7 @@ func (c *controller) agentInit(listenAddr, bindAddrOrInterface, advertiseAddr st
 	c.Unlock()
 
 	go c.handleTableEvents(ch, c.handleEpTableEvent)
+	go c.handleTableEvents(nodeCh, c.handleNodeTableEvent)
 
 	drvEnc := discoverapi.DriverEncryptionConfig{}
 	keys, tags = c.getKeys(subsysIPSec)
@@ -634,6 +637,31 @@ func (n *network) handleDriverTableEvent(ev events.Event) {
 	d.EventNotify(etype, n.ID(), tname, key, value)
 }
 
+func (c *controller) handleNodeTableEvent(ev events.Event) {
+	var (
+		value    []byte
+		isAdd    bool
+		nodeAddr networkdb.NodeAddr
+	)
+	switch event := ev.(type) {
+	case networkdb.CreateEvent:
+		value = event.Value
+		isAdd = true
+	case networkdb.DeleteEvent:
+		value = event.Value
+	case networkdb.UpdateEvent:
+		logrus.Errorf("Unexpected update node table event = %#v", event)
+	}
+
+	err := json.Unmarshal(value, &nodeAddr)
+	if err != nil {
+		logrus.Errorf("Error unmarshalling node table event %v", err)
+		return
+	}
+	c.processNodeDiscovery([]net.IP{nodeAddr.Addr}, isAdd)
+
+}
+
 func (c *controller) handleEpTableEvent(ev events.Event) {
 	var (
 		nid   string
diff --git a/libnetwork/controller.go b/libnetwork/controller.go
index 24d71e4325..08927c4211 100644
--- a/libnetwork/controller.go
+++ b/libnetwork/controller.go
@@ -567,6 +567,12 @@ func (c *controller) pushNodeDiscovery(d driverapi.Driver, cap driverapi.Capabil
 	if c.cfg != nil {
 		addr := strings.Split(c.cfg.Cluster.Address, ":")
 		self = net.ParseIP(addr[0])
+		// if external kvstore is not configured, try swarm-mode config
+		if self == nil {
+			if agent := c.getAgent(); agent != nil {
+				self = net.ParseIP(agent.advertiseAddr)
+			}
+		}
 	}
 
 	if d == nil || cap.DataScope != datastore.GlobalScope || nodes == nil {
diff --git a/libnetwork/networkdb/event_delegate.go b/libnetwork/networkdb/event_delegate.go
index c22d09eba3..6ae0a32ad1 100644
--- a/libnetwork/networkdb/event_delegate.go
+++ b/libnetwork/networkdb/event_delegate.go
@@ -1,12 +1,28 @@
 package networkdb
 
-import "github.com/hashicorp/memberlist"
+import (
+	"encoding/json"
+	"net"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/hashicorp/memberlist"
+)
 
 type eventDelegate struct {
 	nDB *NetworkDB
 }
 
+func (e *eventDelegate) broadcastNodeEvent(addr net.IP, op opType) {
+	value, err := json.Marshal(&NodeAddr{addr})
+	if err == nil {
+		e.nDB.broadcaster.Write(makeEvent(op, NodeTable, "", "", value))
+	} else {
+		logrus.Errorf("Error marshalling node broadcast event %s", addr.String())
+	}
+}
+
 func (e *eventDelegate) NotifyJoin(mn *memberlist.Node) {
+	e.broadcastNodeEvent(mn.Addr, opCreate)
 	e.nDB.Lock()
 	// In case the node is rejoining after a failure or leave,
 	// wait until an explicit join message arrives before adding
@@ -24,6 +40,7 @@ func (e *eventDelegate) NotifyJoin(mn *memberlist.Node) {
 }
 
 func (e *eventDelegate) NotifyLeave(mn *memberlist.Node) {
+	e.broadcastNodeEvent(mn.Addr, opDelete)
 	e.nDB.deleteNodeTableEntries(mn.Name)
 	e.nDB.deleteNetworkEntriesForNode(mn.Name)
 	e.nDB.Lock()
diff --git a/libnetwork/networkdb/watch.go b/libnetwork/networkdb/watch.go
index 2df00fa54f..088b666f01 100644
--- a/libnetwork/networkdb/watch.go
+++ b/libnetwork/networkdb/watch.go
@@ -1,6 +1,10 @@
 package networkdb
 
-import "github.com/docker/go-events"
+import (
+	"net"
+
+	"github.com/docker/go-events"
+)
 
 type opType uint8
 
@@ -17,6 +21,14 @@ type event struct {
 	Value     []byte
 }
 
+// NodeTable represents table event for node join and leave
+const NodeTable = "NodeTable"
+
+// NodeAddr represents the value carried for node event in NodeTable
+type NodeAddr struct {
+	Addr net.IP
+}
+
 // CreateEvent generates a table entry create event to the watchers
 type CreateEvent event