From 217d34f66d840ce3b96833db704bd5a3125a33f4 Mon Sep 17 00:00:00 2001
From: Frank Schroeder <frank.schroeder@gmail.com>
Date: Fri, 30 Jun 2017 22:37:20 +0200
Subject: [PATCH] agent: fix pending data races between localState and agent

This patch creates a local config structure for the local state
which is independent from the agent but populated from its
configuration. This avoids data races between the agent configuration
which can change during tests and concurrent go routines using the
configuraiton at the same time.
---
 agent/local.go | 38 ++++++++++++++++++++++++++++++++++----
 1 file changed, 34 insertions(+), 4 deletions(-)

diff --git a/agent/local.go b/agent/local.go
index e4b8cdc35..e3d30135f 100644
--- a/agent/local.go
+++ b/agent/local.go
@@ -27,6 +27,21 @@ type syncStatus struct {
 	inSync bool // Is this in sync with the server
 }
 
+// localStateConfig is the configuration for the localState. It is
+// popuplated during NewLocalAgent from the agent configuration to avoid
+// race conditions with the agent configuration.
+type localStateConfig struct {
+	ACLToken            string
+	AEInterval          time.Duration
+	AdvertiseAddr       string
+	CheckUpdateInterval time.Duration
+	Datacenter          string
+	NodeID              types.NodeID
+	NodeName            string
+	TaggedAddresses     map[string]string
+	TokenForAgent       string
+}
+
 // localState is used to represent the node's services,
 // and checks. We used it to perform anti-entropy with the
 // catalog representation
@@ -39,7 +54,7 @@ type localState struct {
 	logger *log.Logger
 
 	// Config is the agent config
-	config *Config
+	config localStateConfig
 
 	// delegate is the consul interface to use for keeping in sync
 	delegate delegate
@@ -76,8 +91,23 @@ type localState struct {
 
 // NewLocalState creates a  is used to initialize the local state
 func NewLocalState(c *Config, lg *log.Logger) *localState {
+	lc := localStateConfig{
+		ACLToken:            c.ACLToken,
+		AEInterval:          c.AEInterval,
+		AdvertiseAddr:       c.AdvertiseAddr,
+		CheckUpdateInterval: c.CheckUpdateInterval,
+		Datacenter:          c.Datacenter,
+		NodeID:              c.NodeID,
+		NodeName:            c.NodeName,
+		TaggedAddresses:     map[string]string{},
+		TokenForAgent:       c.GetTokenForAgent(),
+	}
+	for k, v := range c.TaggedAddresses {
+		lc.TaggedAddresses[k] = v
+	}
+
 	return &localState{
-		config:            c,
+		config:            lc,
 		logger:            lg,
 		services:          make(map[string]*structs.NodeService),
 		serviceStatus:     make(map[string]syncStatus),
@@ -413,7 +443,7 @@ func (l *localState) setSyncState() error {
 	req := structs.NodeSpecificRequest{
 		Datacenter:   l.config.Datacenter,
 		Node:         l.config.NodeName,
-		QueryOptions: structs.QueryOptions{Token: l.config.GetTokenForAgent()},
+		QueryOptions: structs.QueryOptions{Token: l.config.TokenForAgent},
 	}
 	var out1 structs.IndexedNodeServices
 	var out2 structs.IndexedHealthChecks
@@ -744,7 +774,7 @@ func (l *localState) syncNodeInfo() error {
 		Address:         l.config.AdvertiseAddr,
 		TaggedAddresses: l.config.TaggedAddresses,
 		NodeMeta:        l.metadata,
-		WriteRequest:    structs.WriteRequest{Token: l.config.GetTokenForAgent()},
+		WriteRequest:    structs.WriteRequest{Token: l.config.TokenForAgent},
 	}
 	var out struct{}
 	err := l.delegate.RPC("Catalog.Register", &req, &out)