From 8b9fbb22a87df8bb13402731c47811625d0315cf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Markus=20Th=C3=B6mmes?= <markusthoemmes@me.com>
Date: Wed, 8 May 2019 08:09:53 +0200
Subject: [PATCH] Add special case for 'no data available ' error

---
 pkg/autoscaler/autoscaler.go | 6 +++++-
 pkg/autoscaler/collector.go  | 7 ++++++-
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/pkg/autoscaler/autoscaler.go b/pkg/autoscaler/autoscaler.go
index 3682288c44cd..9780bb0722a8 100644
--- a/pkg/autoscaler/autoscaler.go
+++ b/pkg/autoscaler/autoscaler.go
@@ -106,7 +106,11 @@ func (a *Autoscaler) Scale(ctx context.Context, now time.Time) (int32, bool) {
 	metricKey := NewMetricKey(a.namespace, a.revision)
 	observedStableConcurrency, observedPanicConcurrency, err := a.metricClient.StableAndPanicConcurrency(metricKey)
 	if err != nil {
-		logger.Errorw("Failed to obtain metrics", zap.Error(err))
+		if err == ErrNoData {
+			logger.Debug("No data to scale on yet")
+		} else {
+			logger.Errorw("Failed to obtain metrics", zap.Error(err))
+		}
 		return 0, false
 	}
 
diff --git a/pkg/autoscaler/collector.go b/pkg/autoscaler/collector.go
index e3aac3037953..d31eb6287b32 100644
--- a/pkg/autoscaler/collector.go
+++ b/pkg/autoscaler/collector.go
@@ -40,6 +40,11 @@ const (
 	bucketSize = 2 * time.Second
 )
 
+var (
+	// ErrNoData denotes that the collector could not calculate data.
+	ErrNoData = errors.New("no data available")
+)
+
 // Metric represents a resource to configure the metric collector with.
 // +k8s:deepcopy-gen=true
 type Metric struct {
@@ -280,7 +285,7 @@ func (c *collection) stableAndPanicConcurrency(now time.Time) (float64, float64,
 	c.buckets.RemoveOlderThan(now.Add(-spec.StableWindow))
 
 	if c.buckets.IsEmpty() {
-		return 0, 0, errors.New("no data available")
+		return 0, 0, ErrNoData
 	}
 
 	panicAverage := aggregation.Average{}