Migrate metrics from OpenCensus to OpenTelemetry

Replace OpenCensus imports (go.opencensus.io/stats, stats/view, tag)
with OpenTelemetry (go.opentelemetry.io/otel, otel/attribute,
otel/metric).

Also updates config-observability.yaml to use OTel configuration
keys (metrics-protocol, tracing-protocol) and removes legacy
OpenCensus keys.

Signed-off-by: Shubham Bhardwaj <shubbhar@redhat.com>

Author: infernus01

config/base/config-observability.yaml

@@ -19,12 +19,14 @@ metadata:
   labels:
     app.kubernetes.io/instance: default
 data:
+  metrics-protocol: prometheus
   _example: |
     ################################
     #                              #
     #    EXAMPLE CONFIGURATION     #
     #                              #
     ################################
+
     # This block is not actually functional configuration,
     # but serves to illustrate the available configuration
     # options and document them in a way that is accessible
@@ -33,18 +35,42 @@ data:
     # These sample configuration options may be copied out of
     # this example block and unindented to be in the data block
     # to actually change the configuration.
-    # metrics.backend-destination field specifies the system metrics destination.
-    # It supports either prometheus (the default) or stackdriver.
-    # Note: Using Stackdriver will incur additional charges.
-    metrics.backend-destination: prometheus
-    # metrics.stackdriver-project-id field specifies the Stackdriver project ID. This
-    # field is optional. When running on GCE, application default credentials will be
-    # used and metrics will be sent to the cluster's project if this field is
-    # not provided.
-    metrics.stackdriver-project-id: "<your stackdriver project id>"
-    # metrics.allow-stackdriver-custom-metrics indicates whether it is allowed
-    # to send metrics to Stackdriver using "global" resource type and custom
-    # metric type. Setting this flag to "true" could cause extra Stackdriver
-    # charge.  If metrics.backend-destination is not Stackdriver, this is
-    # ignored.
-    metrics.allow-stackdriver-custom-metrics: "false"
+
+    # OpenTelemetry Metrics Configuration
+    # Protocol for metrics export (prometheus, grpc, http/protobuf, none)
+    # Default: prometheus
+    metrics-protocol: prometheus
+
+    # Metrics endpoint (for grpc/http protocols)
+    # Default: empty (uses default OTLP endpoint)
+    metrics-endpoint: ""
+
+    # Metrics export interval (e.g., "30s", "1m")
+    # Default: empty (uses SDK default)
+    metrics-export-interval: ""
+
+    # OpenTelemetry Tracing Configuration
+    # Protocol for tracing export (grpc, http/protobuf, none, stdout)
+    # Default: none
+    tracing-protocol: none
+
+    # Tracing endpoint (for grpc/http protocols)
+    # Default: empty
+    tracing-endpoint: ""
+
+    # Tracing sampling rate (0.0 to 1.0)
+    # Default: 1.0 (100% sampling)
+    tracing-sampling-rate: "1.0"
+
+    # Runtime Configuration
+    # Enable profiling (enabled, disabled)
+    # Default: disabled
+    runtime-profiling: disabled
+
+    # Runtime export interval (e.g., "15s")
+    # Default: 15s
+    runtime-export-interval: "15s"
+
+    # Note: Legacy OpenCensus configuration keys (metrics.backend-destination,
+    # metrics.stackdriver-project-id, metrics.allow-stackdriver-custom-metrics)
+    # are no longer recognized. Use the OpenTelemetry options above.

pkg/reconciler/kubernetes/tektonchain/metrics.go

@@ -19,135 +19,62 @@ package tektonchain
 import (
 	"context"
 	"fmt"
+	"sync"
 	"time"
 
 	"github.com/tektoncd/operator/pkg/apis/operator/v1alpha1"
-	"go.opencensus.io/stats"
-	"go.opencensus.io/stats/view"
-	"go.opencensus.io/tag"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/metric"
 	"go.uber.org/zap"
-	"knative.dev/pkg/metrics"
 )
 
 var (
-	rReconcileCount = stats.Float64("chains_reconciled",
-		"metrics of chains reconciled with labels",
-		stats.UnitDimensionless)
+	rReconcileCount metric.Int64Counter
+	once            sync.Once
+	errInitMetrics  error
 )
 
+func initMetrics() error {
+	meter := otel.Meter("github.com/tektoncd/operator/pkg/reconciler/kubernetes/tektonchain")
+	var err error
+	rReconcileCount, err = meter.Int64Counter(
+		"tekton_operator_lifecycle_chains_reconciled_total",
+		metric.WithDescription("metrics of chains reconciled with labels"),
+	)
+	if err != nil {
+		return fmt.Errorf("failed to create chains_reconciled counter: %w", err)
+	}
+	return nil
+}
+
 // Recorder holds keys for Tekton metrics
 type Recorder struct {
-	initialized        bool
-	version            tag.Key
-	taskrunFormat      tag.Key
-	taskrunStorage     tag.Key
-	taskrunSigner      tag.Key
-	pipelinerunFormat  tag.Key
-	pipelinerunStorage tag.Key
-	pipelinerunSigner  tag.Key
-	ociFormat          tag.Key
-	ociStorage         tag.Key
-	ociSigner          tag.Key
-
+	initialized     bool
 	ReportingPeriod time.Duration
 }
 
 // NewRecorder creates a new metrics recorder instance
-// to log the PipelineRun related metrics
 func NewRecorder() (*Recorder, error) {
-	r := &Recorder{
-		initialized: true,
-
-		// Default to 30s intervals.
-		ReportingPeriod: 30 * time.Second,
-	}
-
-	version, err := tag.NewKey("version")
-	if err != nil {
-		return nil, err
-	}
-	r.version = version
-
-	taskrunFormat, err := tag.NewKey("taskrun_format")
-	if err != nil {
-		return nil, err
-	}
-	r.taskrunFormat = taskrunFormat
-
-	taskrunStorage, err := tag.NewKey("taskrun_storage")
-	if err != nil {
-		return nil, err
-	}
-	r.taskrunStorage = taskrunStorage
-
-	taskrunSigner, err := tag.NewKey("taskrun_signer")
-	if err != nil {
-		return nil, err
-	}
-	r.taskrunSigner = taskrunSigner
-
-	pipelinerunFormat, err := tag.NewKey("pipelinerun_format")
-	if err != nil {
-		return nil, err
+	once.Do(func() {
+		errInitMetrics = initMetrics()
+	})
+	if errInitMetrics != nil {
+		return nil, errInitMetrics
 	}
-	r.pipelinerunFormat = pipelinerunFormat
 
-	pipelinerunStorage, err := tag.NewKey("pipelinerun_storage")
-	if err != nil {
-		return nil, err
-	}
-	r.pipelinerunStorage = pipelinerunStorage
-
-	pipelinerunSigner, err := tag.NewKey("pipelinerun_signer")
-	if err != nil {
-		return nil, err
-	}
-	r.pipelinerunSigner = pipelinerunSigner
-
-	ociFormat, err := tag.NewKey("oci_format")
-	if err != nil {
-		return nil, err
-	}
-	r.ociFormat = ociFormat
-
-	ociStorage, err := tag.NewKey("oci_storage")
-	if err != nil {
-		return nil, err
-	}
-	r.ociStorage = ociStorage
-
-	ociSigner, err := tag.NewKey("oci_signer")
-	if err != nil {
-		return nil, err
-	}
-	r.ociSigner = ociSigner
-
-	err = view.Register(
-		&view.View{
-			Description: rReconcileCount.Description(),
-			Measure:     rReconcileCount,
-			Aggregation: view.Count(),
-			TagKeys: []tag.Key{r.version,
-				r.taskrunFormat, r.taskrunStorage, r.taskrunSigner,
-				r.pipelinerunFormat, r.pipelinerunStorage, r.pipelinerunSigner,
-				r.ociFormat, r.ociStorage, r.ociSigner},
-		},
-	)
-
-	if err != nil {
-		r.initialized = false
-		return r, err
+	r := &Recorder{
+		initialized:     true,
+		ReportingPeriod: 30 * time.Second,
 	}
-
 	return r, nil
 }
 
-// Logs when chains is reconciled with version and
-// config labels.
+// Count logs when chains is reconciled with version and config labels.
 func (r *Recorder) Count(version string, spec v1alpha1.TektonChainSpec) error {
 	if !r.initialized {
 		return fmt.Errorf(
-			"ignoring the metrics recording for pipelinee failed to initialize the metrics recorder")
+			"failed to initialize metrics recorder for chains")
 	}
 
 	var taskrunStorage, pipelinerunStorage, ociStorage string
@@ -161,25 +88,20 @@ func (r *Recorder) Count(version string, spec v1alpha1.TektonChainSpec) error {
 		ociStorage = *spec.ArtifactsOCIStorage
 	}
 
-	ctx, err := tag.New(
-		context.Background(),
-		tag.Insert(r.version, version),
-		tag.Insert(r.taskrunFormat, spec.ArtifactsTaskRunFormat),
-		tag.Insert(r.taskrunStorage, taskrunStorage),
-		tag.Insert(r.taskrunSigner, spec.ArtifactsTaskRunSigner),
-		tag.Insert(r.pipelinerunFormat, spec.ArtifactsPipelineRunFormat),
-		tag.Insert(r.pipelinerunStorage, pipelinerunStorage),
-		tag.Insert(r.pipelinerunSigner, spec.ArtifactsPipelineRunSigner),
-		tag.Insert(r.ociFormat, spec.ArtifactsOCIFormat),
-		tag.Insert(r.ociStorage, ociStorage),
-		tag.Insert(r.ociSigner, spec.ArtifactsOCISigner),
+	rReconcileCount.Add(context.Background(), 1,
+		metric.WithAttributes(
+			attribute.String("version", version),
+			attribute.String("taskrun_format", spec.ArtifactsTaskRunFormat),
+			attribute.String("taskrun_storage", taskrunStorage),
+			attribute.String("taskrun_signer", spec.ArtifactsTaskRunSigner),
+			attribute.String("pipelinerun_format", spec.ArtifactsPipelineRunFormat),
+			attribute.String("pipelinerun_storage", pipelinerunStorage),
+			attribute.String("pipelinerun_signer", spec.ArtifactsPipelineRunSigner),
+			attribute.String("oci_format", spec.ArtifactsOCIFormat),
+			attribute.String("oci_storage", ociStorage),
+			attribute.String("oci_signer", spec.ArtifactsOCISigner),
+		),
 	)
-
-	if err != nil {
-		return err
-	}
-
-	metrics.Record(ctx, rReconcileCount.M(1))
 	return nil
 }
 
@@ -192,7 +114,7 @@ func (m *Recorder) LogMetricsWithSpec(version string, spec v1alpha1.TektonChainS
 
 func (m *Recorder) LogMetrics(status, version string, logger *zap.SugaredLogger) {
 	var newSpec v1alpha1.TektonChainSpec
-	err := m.Count(status, newSpec)
+	err := m.Count(version, newSpec)
 	if err != nil {
 		logger.Warnf("%v: Failed to log the metrics : %v", resourceKind, err)
 	}