Merge pull request #330 from prometheus/feature/interface/tabular-targets

Represent targets in a tabular interface.

retrieval/scheduler.go

@@ -25,7 +25,7 @@ const (
 	// The base units for the exponential backoff.
 	DEFAULT_BACKOFF_VALUE_UNIT = time.Second
 	// The maximum allowed backoff time.
-	MAXIMUM_BACKOFF_VALUE = 30 * time.Minute
+	MAXIMUM_BACKOFF_VALUE = 2 * time.Minute
 )
 
 // scheduler is an interface that various scheduling strategies must fulfill

retrieval/target.go

@@ -97,7 +97,10 @@ type Target interface {
 	// time, but it should occur no sooner than it.
 	//
 	// Right now, this is used as the sorting key in TargetPool.
-	scheduledFor() time.Time
+	ScheduledFor() time.Time
+	// EstimatedTimeToExecute emits the amount of time until the next prospective
+	// scheduling opportunity for this target.
+	EstimatedTimeToExecute() time.Duration
 	// Return the last encountered scrape error, if any.
 	LastError() error
 	// The address to which the Target corresponds.  Out of all of the available
@@ -176,11 +179,11 @@ func (t *target) recordScrapeHealth(results chan<- *extraction.Result, timestamp
 	}
 }
 
-func (t *target) Scrape(earliest time.Time, results chan<- *extraction.Result) (err error) {
+func (t *target) Scrape(earliest time.Time, results chan<- *extraction.Result) error {
 	now := time.Now()
 	futureState := t.state
-
-	if err = t.scrape(now, results); err != nil {
+	err := t.scrape(now, results)
+	if err != nil {
 		t.recordScrapeHealth(results, now, false)
 		futureState = UNREACHABLE
 	} else {
@@ -249,23 +252,27 @@ func (t *target) scrape(timestamp time.Time, results chan<- *extraction.Result)
 	return processor.ProcessSingle(buf, results, processOptions)
 }
 
-func (t target) State() TargetState {
+func (t *target) State() TargetState {
 	return t.state
 }
 
-func (t target) scheduledFor() time.Time {
+func (t *target) ScheduledFor() time.Time {
 	return t.scheduler.ScheduledFor()
 }
 
-func (t target) LastError() error {
+func (t *target) EstimatedTimeToExecute() time.Duration {
+	return t.scheduler.ScheduledFor().Sub(time.Now())
+}
+
+func (t *target) LastError() error {
 	return t.lastError
 }
 
-func (t target) Address() string {
+func (t *target) Address() string {
 	return t.address
 }
 
-func (t target) GlobalAddress() string {
+func (t *target) GlobalAddress() string {
 	address := t.address
 	hostname, err := os.Hostname()
 	if err != nil {
@@ -278,7 +285,7 @@ func (t target) GlobalAddress() string {
 	return address
 }
 
-func (t target) BaseLabels() clientmodel.LabelSet {
+func (t *target) BaseLabels() clientmodel.LabelSet {
 	return t.baseLabels
 }
 
@@ -299,7 +306,7 @@ func (t targets) Len() int {
 }
 
 func (t targets) Less(i, j int) bool {
-	return t[i].scheduledFor().Before(t[j].scheduledFor())
+	return t[i].ScheduledFor().Before(t[j].ScheduledFor())
 }
 
 func (t targets) Swap(i, j int) {

retrieval/targetmanager_test.go

@@ -66,7 +66,7 @@ func (t fakeTarget) State() TargetState {
 	return ALIVE
 }
 
-func (t *fakeTarget) scheduledFor() (time time.Time) {
+func (t *fakeTarget) ScheduledFor() (time time.Time) {
 	time = t.schedules[t.scheduleIndex]
 	t.scheduleIndex++
 

retrieval/targetpool.go

@@ -146,7 +146,7 @@ func (p *TargetPool) runIteration(results chan<- *extraction.Result, interval ti
 	for _, target := range p.targets {
 		now := time.Now()
 
-		if target.scheduledFor().After(now) {
+		if target.ScheduledFor().After(now) {
 			// None of the remaining targets are ready to be scheduled. Signal that
 			// we're done processing them in this scrape iteration.
 			continue

storage/metric/operation_test.go

@@ -1838,13 +1838,13 @@ func TestGetValueRangeAtIntervalOp(t *testing.T) {
 
 	var scenarios = []struct {
 		op  getValueRangeAtIntervalOp
-		in  model.Values
-		out model.Values
+		in  Values
+		out Values
 	}{
 		// All values before the first range.
 		{
 			op: testOp,
-			in: model.Values{
+			in: Values{
 				{
 					Timestamp: testInstant.Add(-4 * time.Minute),
 					Value:     1,
@@ -1854,12 +1854,12 @@ func TestGetValueRangeAtIntervalOp(t *testing.T) {
 					Value:     2,
 				},
 			},
-			out: model.Values{},
+			out: Values{},
 		},
 		// Values starting before first range, ending after last.
 		{
 			op: testOp,
-			in: model.Values{
+			in: Values{
 				{
 					Timestamp: testInstant.Add(-4 * time.Minute),
 					Value:     1,
@@ -1917,7 +1917,7 @@ func TestGetValueRangeAtIntervalOp(t *testing.T) {
 					Value:     14,
 				},
 			},
-			out: model.Values{
+			out: Values{
 				{
 					Timestamp: testInstant.Add(-2 * time.Minute),
 					Value:     3,
@@ -1959,17 +1959,17 @@ func TestGetValueRangeAtIntervalOp(t *testing.T) {
 		// Values starting after last range.
 		{
 			op: testOp,
-			in: model.Values{
+			in: Values{
 				{
 					Timestamp: testInstant.Add(21 * time.Minute),
 					Value:     14,
 				},
 			},
-			out: model.Values{},
+			out: Values{},
 		},
 	}
 	for i, scenario := range scenarios {
-		actual := model.Values{}
+		actual := Values{}
 		for !scenario.op.Consumed() {
 			actual = append(actual, scenario.op.ExtractSamples(scenario.in)...)
 		}

web/templates/status.html

@@ -40,23 +40,43 @@
 
     <h2>Targets</h2>
     <div class="grouping_box">
-      <ul>
-        {{range $job, $pool := .TargetPools}}
-          <li>{{$job}}
-            <ul>
-              {{range $pool.Targets}}
-                <li>
-                <a href="{{.GlobalAddress}}">{{.Address}}</a> (State: {{.State}}, Base Labels: {{.BaseLabels}})
+      {{range $job, $pool := .TargetPools}}
+      <h3>{{$job}}</h3>
+        <table>
+          <thead>
+            <tr>
+              <th>Endpoint</th>
+              <th>State</th>
+              <th>Base Labels</th>
+              <th>Next Retrieval</th>
+              <th>Error</th>
+            </tr>
+          </thead>
+          <tbody>
+          {{range $pool.Targets}}
+            <tr>
+              <td>
+                <a href="{{.GlobalAddress}}">{{.Address}}</a>
+              </td>
+              <td>
+                {{.State}}
+              </td>
+              <td>
+                {{.BaseLabels}}
+              </td>
+              <td>
+                {{.EstimatedTimeToExecute}}
+              </td>
+              <td>
                 {{if .LastError}}
-                <br/>
-                <span class="error_text"><b>Scrape error:</b> "{{.LastError}}"</span>
+                <span class="error_text">{{.LastError}}</span>
                 {{end}}
-                </li>
-              {{end}}
-            </ul>
-          </li>
-        {{end}}
-      </ul>
+              </td>
+            </tr>
+          {{end}}
+          </tbody>
+        </table>
+      {{end}}
     </div>
 
     <h2>Curation</h2>