Handle deprecated replicas in conversion (#2723)

Signed-off-by: Pavol Loffay <p.loffay@gmail.com>

apis/v1alpha1/convert.go

@@ -181,10 +181,14 @@ func tov1beta1TA(in OpenTelemetryTargetAllocator) v1beta1.TargetAllocatorEmbedde
 	}
 }
 
+// The conversion takes into account deprecated v1alpha1 spec.minReplicas and spec.maxReplicas.
 func tov1beta1Autoscaler(in *AutoscalerSpec, minReplicas, maxReplicas *int32) *v1beta1.AutoscalerSpec {
-	if in == nil {
+	if in == nil && minReplicas == nil && maxReplicas == nil {
 		return nil
 	}
+	if in == nil {
+		in = &AutoscalerSpec{}
+	}
 
 	var metrics []v1beta1.MetricSpec
 	for _, m := range in.Metrics {

apis/v1alpha1/convert_test.go

@@ -382,6 +382,31 @@ func Test_tov1beta1AndBack_prometheus_selectors(t *testing.T) {
 	})
 }
 
+func Test_tov1beta1AndBack_deprecated_replicas(t *testing.T) {
+	one := int32(1)
+	two := int32(2)
+	colalpha1 := OpenTelemetryCollector{
+		Spec: OpenTelemetryCollectorSpec{
+			MinReplicas: &one,
+			MaxReplicas: &two,
+		},
+	}
+
+	colbeta1 := v1beta1.OpenTelemetryCollector{}
+	err := colalpha1.ConvertTo(&colbeta1)
+	require.NoError(t, err)
+
+	assert.Equal(t, one, *colbeta1.Spec.Autoscaler.MinReplicas)
+	assert.Equal(t, two, *colbeta1.Spec.Autoscaler.MaxReplicas)
+
+	err = colalpha1.ConvertFrom(&colbeta1)
+	require.NoError(t, err)
+	assert.Nil(t, colalpha1.Spec.MinReplicas)
+	assert.Nil(t, colalpha1.Spec.MaxReplicas)
+	assert.Equal(t, one, *colalpha1.Spec.Autoscaler.MinReplicas)
+	assert.Equal(t, two, *colalpha1.Spec.Autoscaler.MaxReplicas)
+}
+
 func createTA() OpenTelemetryTargetAllocator {
 	replicas := int32(2)
 	runAsNonRoot := true