Add conversion go APIs (open-telemetry#2711)

* Add conversion go APIs

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

* Fix

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

* Fix

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

* Fix

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

---------

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

Author: pavolloffay

apis/v1alpha1/convert.go

@@ -16,15 +16,53 @@ package v1alpha1
 
 import (
 	"errors"
+	"fmt"
 
 	"gopkg.in/yaml.v3"
 	appsv1 "k8s.io/api/apps/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"sigs.k8s.io/controller-runtime/pkg/conversion"
 
 	"github.com/open-telemetry/opentelemetry-operator/apis/v1beta1"
 )
 
-func Tov1beta1(in OpenTelemetryCollector) (v1beta1.OpenTelemetryCollector, error) {
+var _ conversion.Convertible = &OpenTelemetryCollector{}
+
+func (src *OpenTelemetryCollector) ConvertTo(dstRaw conversion.Hub) error {
+	switch t := dstRaw.(type) {
+	case *v1beta1.OpenTelemetryCollector:
+		dst := dstRaw.(*v1beta1.OpenTelemetryCollector)
+		convertedSrc, err := tov1beta1(*src)
+		if err != nil {
+			return fmt.Errorf("failed to convert to v1beta1: %w", err)
+		}
+		dst.ObjectMeta = convertedSrc.ObjectMeta
+		dst.Spec = convertedSrc.Spec
+		dst.Status = convertedSrc.Status
+	default:
+		return fmt.Errorf("unsupported type %v", t)
+	}
+	return nil
+}
+
+func (dst *OpenTelemetryCollector) ConvertFrom(srcRaw conversion.Hub) error {
+	switch t := srcRaw.(type) {
+	case *v1beta1.OpenTelemetryCollector:
+		src := srcRaw.(*v1beta1.OpenTelemetryCollector)
+		srcConverted, err := tov1alpha1(*src)
+		if err != nil {
+			return fmt.Errorf("failed to convert to v1alpha1: %w", err)
+		}
+		dst.ObjectMeta = srcConverted.ObjectMeta
+		dst.Spec = srcConverted.Spec
+		dst.Status = srcConverted.Status
+	default:
+		return fmt.Errorf("unsupported type %v", t)
+	}
+	return nil
+}
+
+func tov1beta1(in OpenTelemetryCollector) (v1beta1.OpenTelemetryCollector, error) {
 	copy := in.DeepCopy()
 	cfg := &v1beta1.Config{}
 	if err := yaml.Unmarshal([]byte(copy.Spec.Config), cfg); err != nil {
@@ -120,6 +158,7 @@ func tov1beta1TA(in OpenTelemetryTargetAllocator) v1beta1.TargetAllocatorEmbedde
 		PrometheusCR: v1beta1.TargetAllocatorPrometheusCR{
 			Enabled:        in.PrometheusCR.Enabled,
 			ScrapeInterval: in.PrometheusCR.ScrapeInterval,
+			// prometheus_cr.pod_monitor_selector shouldn't be nil when selector is empty
 			PodMonitorSelector: &metav1.LabelSelector{
 				MatchLabels: in.PrometheusCR.PodMonitorSelector,
 			},
@@ -236,7 +275,7 @@ func tov1alpha1(in v1beta1.OpenTelemetryCollector) (*OpenTelemetryCollector, err
 			SecurityContext:      copy.Spec.SecurityContext,
 			PodSecurityContext:   copy.Spec.PodSecurityContext,
 			PodAnnotations:       copy.Spec.PodAnnotations,
-			TargetAllocator:      tov1alpha1TA(in.Spec.TargetAllocator),
+			TargetAllocator:      tov1alpha1TA(copy.Spec.TargetAllocator),
 			Mode:                 Mode(copy.Spec.Mode),
 			ServiceAccount:       copy.Spec.ServiceAccount,
 			Image:                copy.Spec.Image,

apis/v1alpha1/convert_test.go

@@ -62,7 +62,7 @@ func Test_tov1beta1_config(t *testing.T) {
 			},
 		}
 
-		cfgV2, err := Tov1beta1(cfgV1)
+		cfgV2, err := tov1beta1(cfgV1)
 		assert.Nil(t, err)
 		assert.NotNil(t, cfgV2)
 		assert.Equal(t, cfgV1.Spec.Args, cfgV2.Spec.Args)
@@ -79,7 +79,7 @@ func Test_tov1beta1_config(t *testing.T) {
 			},
 		}
 
-		_, err := Tov1beta1(cfgV1)
+		_, err := tov1beta1(cfgV1)
 		assert.ErrorContains(t, err, "could not convert config json to v1beta1.Config")
 	})
 }
@@ -310,7 +310,7 @@ func Test_tov1beta1AndBack(t *testing.T) {
 		},
 	}
 
-	colbeta1, err := Tov1beta1(*colalpha1)
+	colbeta1, err := tov1beta1(*colalpha1)
 	require.NoError(t, err)
 	colalpha1Converted, err := tov1alpha1(colbeta1)
 	require.NoError(t, err)
@@ -421,3 +421,71 @@ func createTA() OpenTelemetryTargetAllocator {
 		},
 	}
 }
+
+func TestConvertTo(t *testing.T) {
+	col := OpenTelemetryCollector{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "otel",
+		},
+		Spec: OpenTelemetryCollectorSpec{
+			ServiceAccount: "otelcol",
+		},
+		Status: OpenTelemetryCollectorStatus{
+			Image: "otel/col",
+		},
+	}
+	colbeta1 := v1beta1.OpenTelemetryCollector{}
+	err := col.ConvertTo(&colbeta1)
+	require.NoError(t, err)
+	assert.Equal(t, v1beta1.OpenTelemetryCollector{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "otel",
+		},
+		Spec: v1beta1.OpenTelemetryCollectorSpec{
+			OpenTelemetryCommonFields: v1beta1.OpenTelemetryCommonFields{
+				ServiceAccount: "otelcol",
+			},
+			TargetAllocator: v1beta1.TargetAllocatorEmbedded{
+				PrometheusCR: v1beta1.TargetAllocatorPrometheusCR{
+					PodMonitorSelector:     &metav1.LabelSelector{},
+					ServiceMonitorSelector: &metav1.LabelSelector{},
+				},
+			},
+		},
+		Status: v1beta1.OpenTelemetryCollectorStatus{
+			Image: "otel/col",
+		},
+	}, colbeta1)
+}
+
+func TestConvertFrom(t *testing.T) {
+	colbeta1 := v1beta1.OpenTelemetryCollector{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "otel",
+		},
+		Spec: v1beta1.OpenTelemetryCollectorSpec{
+			OpenTelemetryCommonFields: v1beta1.OpenTelemetryCommonFields{
+				ServiceAccount: "otelcol",
+			},
+		},
+		Status: v1beta1.OpenTelemetryCollectorStatus{
+			Image: "otel/col",
+		},
+	}
+	col := OpenTelemetryCollector{}
+	err := col.ConvertFrom(&colbeta1)
+	require.NoError(t, err)
+	// set config to empty. The v1beta1 marshals config with empty receivers, exporters..
+	col.Spec.Config = ""
+	assert.Equal(t, OpenTelemetryCollector{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: "otel",
+		},
+		Spec: OpenTelemetryCollectorSpec{
+			ServiceAccount: "otelcol",
+		},
+		Status: OpenTelemetryCollectorStatus{
+			Image: "otel/col",
+		},
+	}, col)
+}

apis/v1beta1/opentelemetrycollector_types.go

@@ -334,6 +334,8 @@ type OpenTelemetryCollector struct {
 	Status OpenTelemetryCollectorStatus `json:"status,omitempty"`
 }
 
+func (*OpenTelemetryCollector) Hub() {}
+
 //+kubebuilder:object:root=true
 
 // OpenTelemetryCollectorList contains a list of OpenTelemetryCollector.

controllers/opentelemetrycollector_controller.go

@@ -37,6 +37,7 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/client"
 
 	"github.com/open-telemetry/opentelemetry-operator/apis/v1alpha1"
+	"github.com/open-telemetry/opentelemetry-operator/apis/v1beta1"
 	"github.com/open-telemetry/opentelemetry-operator/internal/autodetect/openshift"
 	"github.com/open-telemetry/opentelemetry-operator/internal/config"
 	"github.com/open-telemetry/opentelemetry-operator/internal/manifests"
@@ -130,7 +131,8 @@ func (r *OpenTelemetryCollectorReconciler) findOtelOwnedObjects(ctx context.Cont
 }
 
 func (r *OpenTelemetryCollectorReconciler) getParams(instance v1alpha1.OpenTelemetryCollector) (manifests.Params, error) {
-	otelCol, err := v1alpha1.Tov1beta1(instance)
+	otelCol := v1beta1.OpenTelemetryCollector{}
+	err := instance.ConvertTo(&otelCol)
 	if err != nil {
 		return manifests.Params{}, err
 	}

pkg/sidecar/pod_test.go

@@ -47,33 +47,35 @@ func TestAddSidecarWhenNoSidecarExists(t *testing.T) {
 			Volumes: []corev1.Volume{{}},
 		},
 	}
-	otelcol, err := v1alpha1.Tov1beta1(
-		v1alpha1.OpenTelemetryCollector{
-			ObjectMeta: metav1.ObjectMeta{
-				Name:      "otelcol-sample-with-a-name-that-is-longer-than-sixty-three-characters",
-				Namespace: "some-app",
-			},
-			Spec: v1alpha1.OpenTelemetryCollectorSpec{
-				Ports: []corev1.ServicePort{
-					{
-						Name:     "metrics",
-						Port:     8888,
-						Protocol: corev1.ProtocolTCP,
-					},
+
+	v1alpha1Col := v1alpha1.OpenTelemetryCollector{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      "otelcol-sample-with-a-name-that-is-longer-than-sixty-three-characters",
+			Namespace: "some-app",
+		},
+		Spec: v1alpha1.OpenTelemetryCollectorSpec{
+			Ports: []corev1.ServicePort{
+				{
+					Name:     "metrics",
+					Port:     8888,
+					Protocol: corev1.ProtocolTCP,
 				},
-				InitContainers: []corev1.Container{
-					{
-						Name: "test",
-					},
+			},
+			InitContainers: []corev1.Container{
+				{
+					Name: "test",
 				},
-				Config: `
+			},
+			Config: `
 receivers:
 exporters:
 processors:
 `,
-			},
 		},
-	)
+	}
+
+	otelcol := v1beta1.OpenTelemetryCollector{}
+	err := v1alpha1Col.ConvertTo(&otelcol)
 	require.NoError(t, err)
 	otelcolYaml, err := otelcol.Spec.Config.Yaml()
 	require.NoError(t, err)

pkg/sidecar/podmutator.go

@@ -27,6 +27,7 @@ import (
 	"sigs.k8s.io/controller-runtime/pkg/client"
 
 	"github.com/open-telemetry/opentelemetry-operator/apis/v1alpha1"
+	"github.com/open-telemetry/opentelemetry-operator/apis/v1beta1"
 	"github.com/open-telemetry/opentelemetry-operator/internal/config"
 	"github.com/open-telemetry/opentelemetry-operator/internal/webhook/podmutation"
 )
@@ -97,7 +98,8 @@ func (p *sidecarPodMutator) Mutate(ctx context.Context, ns corev1.Namespace, pod
 	// we should add the sidecar.
 	logger.V(1).Info("injecting sidecar into pod", "otelcol-namespace", otelcol.Namespace, "otelcol-name", otelcol.Name)
 
-	otc, err := v1alpha1.Tov1beta1(otelcol)
+	otc := v1beta1.OpenTelemetryCollector{}
+	err = otelcol.ConvertTo(&otc)
 	if err != nil {
 		return corev1.Pod{}, err
 	}