Merge pull request #2143 from prometheus/beorn7/fix

Protect against negative time ranges.

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## 1.2.2 / 2016-10-30
 
+* [BUGFIX] Correctly handle on() in alerts.
 * [BUGFIX] UI: Deal properly with aborted requests.
 * [BUGFIX] UI: Decode URL query parameters properly.
 * [BUGFIX] Storage: Deal better with data corruption (non-monotonic timestamps).

cmd/prometheus/config.go

@@ -262,6 +262,10 @@ func parse(args []string) error {
 		return err
 	}
 
+	if promql.StalenessDelta < 0 {
+		return fmt.Errorf("negative staleness delta: %s", promql.StalenessDelta)
+	}
+
 	if err := parsePrometheusURL(); err != nil {
 		return err
 	}

storage/local/storage.go

@@ -480,6 +480,10 @@ func (bit *boundedIterator) Close() {
 
 // QueryRange implements Storage.
 func (s *MemorySeriesStorage) QueryRange(_ context.Context, from, through model.Time, matchers ...*metric.LabelMatcher) ([]SeriesIterator, error) {
+	if through.Before(from) {
+		// In that case, nothing will match.
+		return nil, nil
+	}
 	fpSeriesPairs, err := s.seriesForLabelMatchers(from, through, matchers...)
 	if err != nil {
 		return nil, err
@@ -494,6 +498,9 @@ func (s *MemorySeriesStorage) QueryRange(_ context.Context, from, through model.
 
 // QueryInstant implements Storage.
 func (s *MemorySeriesStorage) QueryInstant(_ context.Context, ts model.Time, stalenessDelta time.Duration, matchers ...*metric.LabelMatcher) ([]SeriesIterator, error) {
+	if stalenessDelta < 0 {
+		panic("negative staleness delta")
+	}
 	from := ts.Add(-stalenessDelta)
 	through := ts
 

storage/local/storage_test.go

@@ -504,6 +504,39 @@ func BenchmarkQueryRange(b *testing.B) {
 	})
 }
 
+func TestQueryRangeThroughBeforeFrom(t *testing.T) {
+	now := model.Now()
+	insertStart := now.Add(-2 * time.Hour)
+
+	s, closer := NewTestStorage(t, 2)
+	defer closer.Close()
+
+	// Stop maintenance loop to prevent actual purging.
+	close(s.loopStopping)
+	<-s.loopStopped
+	<-s.logThrottlingStopped
+	// Recreate channel to avoid panic when we really shut down.
+	s.loopStopping = make(chan struct{})
+
+	for i := 0; i < 8192; i++ {
+		s.Append(&model.Sample{
+			Metric:    model.Metric{"__name__": "testmetric", "job": "test"},
+			Timestamp: insertStart.Add(time.Duration(i) * time.Second),
+			Value:     model.SampleValue(rand.Float64()),
+		})
+	}
+	s.WaitForIndexing()
+
+	lm, _ := metric.NewLabelMatcher(metric.Equal, "job", "test")
+	iters, err := s.QueryRange(context.Background(), now.Add(-30*time.Minute), now.Add(-90*time.Minute), lm)
+	if err != nil {
+		t.Error(err)
+	}
+	if len(iters) != 0 {
+		t.Errorf("expected no iters to be returned, got %d", len(iters))
+	}
+}
+
 func TestRetentionCutoff(t *testing.T) {
 	now := model.Now()
 	insertStart := now.Add(-2 * time.Hour)