``TargetManager`` and ``TargetPool`` ass pointers.

retrieval/interface_test.go

@@ -20,6 +20,7 @@ import (
 func TestInterfaces(t *testing.T) {
 	var (
 		_ Target         = &target{}
+		_ TargetManager  = &targetManager{}
 		_ healthReporter = target{}
 		_ scheduler      = &healthScheduler{}
 	)

retrieval/targetmanager.go

@@ -31,36 +31,36 @@ type TargetManager interface {
 
 type targetManager struct {
 	requestAllowance chan bool
-	pools            map[time.Duration]TargetPool
+	pools            map[time.Duration]*TargetPool
 	results          chan Result
 }
 
 func NewTargetManager(results chan Result, requestAllowance int) TargetManager {
-	return targetManager{
+	return &targetManager{
 		requestAllowance: make(chan bool, requestAllowance),
 		results:          results,
-		pools:            make(map[time.Duration]TargetPool),
+		pools:            make(map[time.Duration]*TargetPool),
 	}
 }
 
-func (m targetManager) acquire() {
+func (m *targetManager) acquire() {
 	m.requestAllowance <- true
 }
 
-func (m targetManager) release() {
+func (m *targetManager) release() {
 	<-m.requestAllowance
 }
 
-func (m targetManager) Add(t Target) {
+func (m *targetManager) Add(t Target) {
 	targetPool, ok := m.pools[t.Interval()]
 
 	if !ok {
-		targetPool.manager = m
+		targetPool = NewTargetPool(m)
 		log.Printf("Pool %s does not exist; creating and starting...", t.Interval())
 		go targetPool.Run(m.results, t.Interval())
 	}
 
-	heap.Push(&targetPool, t)
+	heap.Push(targetPool, t)
 	m.pools[t.Interval()] = targetPool
 }
 
@@ -68,7 +68,7 @@ func (m targetManager) Remove(t Target) {
 	panic("not implemented")
 }
 
-func (m targetManager) AddTargetsFromConfig(config *config.Config) {
+func (m *targetManager) AddTargetsFromConfig(config *config.Config) {
 	for _, job := range config.Jobs {
 		for _, configTargets := range job.Targets {
 			baseLabels := model.LabelSet{

retrieval/targetmanager_test.go

@@ -0,0 +1,87 @@
+// Copyright 2013 Prometheus Team
+// 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
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package retrieval
+
+import (
+	"github.com/matttproud/prometheus/utility/test"
+	"testing"
+	"time"
+)
+
+type fakeTarget struct {
+	scrapeCount   int
+	schedules     []time.Time
+	interval      time.Duration
+	scheduleIndex int
+}
+
+func (t fakeTarget) Address() string {
+	return "fake"
+}
+
+func (t fakeTarget) Interval() time.Duration {
+	return t.interval
+}
+
+func (t *fakeTarget) Scrape(e time.Time, r chan Result) error {
+	t.scrapeCount++
+
+	return nil
+}
+
+func (t fakeTarget) State() TargetState {
+	return ALIVE
+}
+
+func (t *fakeTarget) scheduledFor() (time time.Time) {
+	time = t.schedules[t.scheduleIndex]
+	t.scheduleIndex++
+
+	return
+}
+
+func testTargetManager(t test.Tester) {
+	results := make(chan Result, 5)
+	targetManager := NewTargetManager(results, 3)
+
+	target1GroupA := &fakeTarget{
+		schedules: []time.Time{time.Now()},
+		interval:  time.Minute,
+	}
+	target2GroupA := &fakeTarget{
+		schedules: []time.Time{time.Now()},
+		interval:  time.Minute,
+	}
+
+	targetManager.Add(target1GroupA)
+	targetManager.Add(target2GroupA)
+
+	target1GroupB := &fakeTarget{
+		schedules: []time.Time{time.Now()},
+		interval:  time.Minute * 2,
+	}
+
+	targetManager.Add(target1GroupB)
+
+}
+
+func TestTargetManager(t *testing.T) {
+	testTargetManager(t)
+}
+
+func BenchmarkTargetManager(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		testTargetManager(b)
+	}
+}

retrieval/targetpool.go

@@ -8,14 +8,14 @@ import (
 
 type TargetPool struct {
 	done    chan bool
-	targets []*target
+	targets []Target
 	manager TargetManager
 }
 
-func NewTargetPool(m TargetManager) (p TargetPool) {
-	p.manager = m
-
-	return
+func NewTargetPool(m TargetManager) (p *TargetPool) {
+	return &TargetPool{
+		manager: m,
+	}
 }
 
 func (p TargetPool) Len() int {
@@ -37,7 +37,7 @@ func (p *TargetPool) Pop() interface{} {
 }
 
 func (p *TargetPool) Push(element interface{}) {
-	p.targets = append(p.targets, element.(*target))
+	p.targets = append(p.targets, element.(Target))
 }
 
 func (p TargetPool) Swap(i, j int) {
@@ -62,7 +62,7 @@ func (p TargetPool) Stop() {
 	p.done <- true
 }
 
-func (p *TargetPool) runSingle(earliest time.Time, results chan Result, t *target) {
+func (p *TargetPool) runSingle(earliest time.Time, results chan Result, t Target) {
 	p.manager.acquire()
 	defer p.manager.release()
 
@@ -71,7 +71,7 @@ func (p *TargetPool) runSingle(earliest time.Time, results chan Result, t *targe
 
 func (p *TargetPool) runIteration(results chan Result) {
 	for i := 0; i < p.Len(); i++ {
-		target := heap.Pop(p).(*target)
+		target := heap.Pop(p).(Target)
 		if target == nil {
 			break
 		}