From a7811b4e339ebe8ebd621c8f6c4dee54c246626c Mon Sep 17 00:00:00 2001
From: Marcos Lilljedahl <marcosnils@gmail.com>
Date: Fri, 2 Dec 2016 10:29:41 -0300
Subject: [PATCH] Omit race conditions and update swarm info events

---
 docker-compose.yml                  |  4 ++--
 services/check_swarm_status_task.go |  2 ++
 services/collect_stats_task.go      | 18 +++++++++---------
 services/session.go                 |  3 ++-
 4 files changed, 15 insertions(+), 12 deletions(-)

diff --git a/docker-compose.yml b/docker-compose.yml
index 407ce90..75b3133 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -1,12 +1,12 @@
 version: '2'
 services:
-    web:
+    pwd:
         # pwd daemon container always needs to be named this way
         container_name: pwd
         # use the latest golang image
         image: golang
         # go to the right place and starts the app
-        command: /bin/sh -c 'cd /go/src/github.com/franela/play-with-docker; go run api.go'
+        command: /bin/sh -c 'cd /go/src/github.com/franela/play-with-docker; go run -race api.go'
         ports:
             # app exposes port 3000
             - "3000:3000"
diff --git a/services/check_swarm_status_task.go b/services/check_swarm_status_task.go
index a892d18..ede3da0 100644
--- a/services/check_swarm_status_task.go
+++ b/services/check_swarm_status_task.go
@@ -9,6 +9,8 @@ func (c checkSwarmStatusTask) Run(i *Instance) {
 	if info, err := GetDaemonInfo(i); err == nil {
 		if info.Swarm.LocalNodeState != swarm.LocalNodeStateInactive && info.Swarm.LocalNodeState != swarm.LocalNodeStateLocked {
 			i.IsManager = &info.Swarm.ControlAvailable
+		} else {
+			i.IsManager = nil
 		}
 	}
 
diff --git a/services/collect_stats_task.go b/services/collect_stats_task.go
index 13b7d43..330edcf 100644
--- a/services/collect_stats_task.go
+++ b/services/collect_stats_task.go
@@ -13,7 +13,6 @@ type collectStatsTask struct {
 	mem        float64
 	memLimit   float64
 	memPercent float64
-	v          *types.StatsJSON
 
 	cpuPercent     float64
 	previousCPU    uint64
@@ -27,24 +26,25 @@ func (c collectStatsTask) Run(i *Instance) {
 		return
 	}
 	dec := json.NewDecoder(reader)
-	e := dec.Decode(&c.v)
+	var v *types.StatsJSON
+	e := dec.Decode(&v)
 	if e != nil {
 		log.Println("Error while trying to collect instance stats", e)
 		return
 	}
 	// Memory
-	if c.v.MemoryStats.Limit != 0 {
-		c.memPercent = float64(c.v.MemoryStats.Usage) / float64(c.v.MemoryStats.Limit) * 100.0
+	if v.MemoryStats.Limit != 0 {
+		c.memPercent = float64(v.MemoryStats.Usage) / float64(v.MemoryStats.Limit) * 100.0
 	}
-	c.mem = float64(c.v.MemoryStats.Usage)
-	c.memLimit = float64(c.v.MemoryStats.Limit)
+	c.mem = float64(v.MemoryStats.Usage)
+	c.memLimit = float64(v.MemoryStats.Limit)
 
 	i.Mem = fmt.Sprintf("%.2f%% (%s / %s)", c.memPercent, units.BytesSize(c.mem), units.BytesSize(c.memLimit))
 
 	// cpu
-	c.previousCPU = c.v.PreCPUStats.CPUUsage.TotalUsage
-	c.previousSystem = c.v.PreCPUStats.SystemUsage
-	c.cpuPercent = calculateCPUPercentUnix(c.previousCPU, c.previousSystem, c.v)
+	c.previousCPU = v.PreCPUStats.CPUUsage.TotalUsage
+	c.previousSystem = v.PreCPUStats.SystemUsage
+	c.cpuPercent = calculateCPUPercentUnix(c.previousCPU, c.previousSystem, v)
 	i.Cpu = fmt.Sprintf("%.2f%%", c.cpuPercent)
 }
 
diff --git a/services/session.go b/services/session.go
index 49f3e24..de9eea3 100644
--- a/services/session.go
+++ b/services/session.go
@@ -66,7 +66,8 @@ func (s *Session) SchedulePeriodicTasks() {
 		for range s.ticker.C {
 			var wg = sync.WaitGroup{}
 			wg.Add(len(s.Instances))
-			for _, i := range s.Instances {
+			for _, ins := range s.Instances {
+				var i *Instance = ins
 				if i.dockerClient == nil {
 					// Need to create client to the DinD docker daemon