From 59af5d28adf679af1a537cd03781577b4f518f70 Mon Sep 17 00:00:00 2001
From: Alfonso Acosta <fons@weave.works>
Date: Tue, 29 Mar 2016 16:44:25 +0000
Subject: [PATCH] Review feedback: merge host controls with reporter

---
 probe/host/controls.go      | 19 +++++--------------
 probe/host/reporter.go      | 14 ++++++++++++--
 probe/host/reporter_test.go |  2 +-
 prog/probe.go               |  7 +++----
 4 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/probe/host/controls.go b/probe/host/controls.go
index c7d8d878ca..0ecad9f59e 100644
--- a/probe/host/controls.go
+++ b/probe/host/controls.go
@@ -15,24 +15,15 @@ const (
 	ExecHost = "host_exec"
 )
 
-// Controls handles controls for a hosts.
-type Controls struct {
-	pipes controls.PipeClient
+func (r *Reporter) registerControls() {
+	controls.Register(ExecHost, r.execHost)
 }
 
-// NewControls creates new host controls.
-func NewControls(pipes controls.PipeClient) *Controls {
-	c := &Controls{pipes: pipes}
-	controls.Register(ExecHost, c.execHost)
-	return c
-}
-
-// Stop stops the host controls.
-func (*Controls) Stop() {
+func (*Reporter) deregisterControls() {
 	controls.Rm(ExecHost)
 }
 
-func (c *Controls) execHost(req xfer.Request) xfer.Response {
+func (r *Reporter) execHost(req xfer.Request) xfer.Response {
 	cmd := exec.Command(hostShellCmd[0], hostShellCmd[1:]...)
 	cmd.Env = []string{"TERM=xterm"}
 	ptyPipe, err := pty.Start(cmd)
@@ -40,7 +31,7 @@ func (c *Controls) execHost(req xfer.Request) xfer.Response {
 		return xfer.ResponseError(err)
 	}
 
-	id, pipe, err := controls.NewPipeFromEnds(nil, ptyPipe, c.pipes, req.AppID)
+	id, pipe, err := controls.NewPipeFromEnds(nil, ptyPipe, r.pipes, req.AppID)
 	if err != nil {
 		return xfer.ResponseError(err)
 	}
diff --git a/probe/host/reporter.go b/probe/host/reporter.go
index eced090eb0..23b7c48e46 100644
--- a/probe/host/reporter.go
+++ b/probe/host/reporter.go
@@ -6,6 +6,7 @@ import (
 	"time"
 
 	"github.com/weaveworks/scope/common/mtime"
+	"github.com/weaveworks/scope/probe/controls"
 	"github.com/weaveworks/scope/report"
 )
 
@@ -37,16 +38,20 @@ type Reporter struct {
 	hostID   string
 	hostName string
 	probeID  string
+	pipes    controls.PipeClient
 }
 
 // NewReporter returns a Reporter which produces a report containing host
 // topology for this host.
-func NewReporter(hostID, hostName, probeID string) *Reporter {
-	return &Reporter{
+func NewReporter(hostID, hostName, probeID string, pipes controls.PipeClient) *Reporter {
+	r := &Reporter{
 		hostID:   hostID,
 		hostName: hostName,
 		probeID:  probeID,
+		pipes:    pipes,
 	}
+	r.registerControls()
+	return r
 }
 
 // Name of this reporter, for metrics gathering
@@ -119,3 +124,8 @@ func (r *Reporter) Report() (report.Report, error) {
 
 	return rep, nil
 }
+
+// Stop stops the reporter.
+func (r *Reporter) Stop() {
+	r.deregisterControls()
+}
diff --git a/probe/host/reporter_test.go b/probe/host/reporter_test.go
index 86abd89fe9..3933c1e276 100644
--- a/probe/host/reporter_test.go
+++ b/probe/host/reporter_test.go
@@ -58,7 +58,7 @@ func TestReporter(t *testing.T) {
 	host.GetMemoryUsageBytes = func() (float64, float64) { return 60.0, 100.0 }
 	host.GetLocalNetworks = func() ([]*net.IPNet, error) { return []*net.IPNet{ipnet}, nil }
 
-	rpt, err := host.NewReporter(hostID, hostname, probeID).Report()
+	rpt, err := host.NewReporter(hostID, hostname, probeID, nil).Report()
 	if err != nil {
 		t.Fatal(err)
 	}
diff --git a/prog/probe.go b/prog/probe.go
index 79408f9b4d..7ae166747f 100644
--- a/prog/probe.go
+++ b/prog/probe.go
@@ -129,9 +129,6 @@ func probeMain() {
 	})
 	defer clients.Stop()
 
-	hostControls := host.NewControls(clients)
-	defer hostControls.Stop()
-
 	resolver := appclient.NewResolver(targets, net.LookupIP, clients.Set)
 	defer resolver.Stop()
 
@@ -143,9 +140,11 @@ func probeMain() {
 
 	p := probe.New(*spyInterval, *publishInterval, clients)
 	p.AddTicker(processCache)
+	hostReporter := host.NewReporter(hostID, hostName, probeID, clients)
+	defer hostReporter.Stop()
 	p.AddReporter(
 		endpointReporter,
-		host.NewReporter(hostID, hostName, probeID),
+		hostReporter,
 		process.NewReporter(processCache, hostID, process.GetDeltaTotalJiffies),
 	)
 	p.AddTagger(probe.NewTopologyTagger(), host.NewTagger(hostID))