adding otel functionality

Signed-off-by: Andrew Steurer <andrew.steurer@fermyon.com>

api/v1alpha1/spinappexecutor_types.go

@@ -48,6 +48,9 @@ type ExecutorDeploymentConfig struct {
 	// will be created containing the certificates. If no secret name is
 	// defined in `CACertSecret` the secret name will be `spin-ca`.
 	InstallDefaultCACerts bool `json:"installDefaultCACerts,omitempty"`
+
+	// Otel provides Kubernetes Bindings to Otel Variables.
+	Otel *OtelConfig `json:"otel,omitempty"`
 }
 
 // SpinAppExecutorStatus defines the observed state of SpinAppExecutor
@@ -56,6 +59,18 @@ type SpinAppExecutorStatus struct {
 	// Important: Run "make" to regenerate code after modifying this file
 }
 
+// OtelConfig is the supported environment variables for OpenTelemetry
+type OtelConfig struct {
+	// ExporterOtlpEndpoint configures the default combined otlp endpoint for sending telemetry
+	ExporterOtlpEndpoint string `json:"exporter_otlp_endpoint,omitempty"`
+	// ExporterOtlpTracesEndpoint configures the trace-specific otlp endpoint
+	ExporterOtlpTracesEndpoint string `json:"exporter_otlp_traces_endpoint,omitempty"`
+	// ExporterOtlpMetricsEndpoint configures the metrics-specific otlp endpoint
+	ExporterOtlpMetricsEndpoint string `json:"exporter_otlp_metrics_endpoint,omitempty"`
+	// ExporterOtlpLogsEndpoint configures the logs-specific otlp endpoint
+	ExporterOtlpLogsEndpoint string `json:"exporter_otlp_logs_endpoint,omitempty"`
+}
+
 //+kubebuilder:object:root=true
 //+kubebuilder:subresource:status
 

config/crd/bases/core.spinoperator.dev_spinappexecutors.yaml

@@ -61,6 +61,26 @@ spec:
                       will be created containing the certificates. If no secret name is
                       defined in `CACertSecret` the secret name will be `spin-ca`.
                     type: boolean
+                  otel:
+                    description: Otel provides Kubernetes Bindings to Otel Variables.
+                    properties:
+                      exporter_otlp_endpoint:
+                        description: ExporterOtlpEndpoint configures the default combined
+                          otlp endpoint for sending telemetry
+                        type: string
+                      exporter_otlp_logs_endpoint:
+                        description: ExporterOtlpLogsEndpoint configures the logs-specific
+                          otlp endpoint
+                        type: string
+                      exporter_otlp_metrics_endpoint:
+                        description: ExporterOtlpMetricsEndpoint configures the metrics-specific
+                          otlp endpoint
+                        type: string
+                      exporter_otlp_traces_endpoint:
+                        description: ExporterOtlpTracesEndpoint configures the trace-specific
+                          otlp endpoint
+                        type: string
+                    type: object
                   runtimeClassName:
                     description: |-
                       RuntimeClassName is the runtime class name that should be used by pods created

config/samples/otel.yaml

@@ -0,0 +1,20 @@
+apiVersion: core.spinoperator.dev/v1alpha1
+kind: SpinApp
+metadata:
+  name: otel-spinapp
+spec:
+  image: ghcr.io/spinkube/spin-operator/cpu-load-gen:20240311-163328-g1121986
+  executor: otel-shim-executor
+  replicas: 1
+---
+apiVersion: core.spinoperator.dev/v1alpha1
+kind: SpinAppExecutor
+metadata:
+  name: otel-shim-executor
+spec:
+  createDeployment: true
+  deploymentConfig:
+    runtimeClassName: wasmtime-spin-v2
+    installDefaultCACerts: true
+    otel:
+      exporter_otlp_endpoint: http://otel-collector.default.svc.cluster.local:4318

internal/controller/deployment.go

@@ -103,8 +103,9 @@ func ConstructVolumeMountsForApp(ctx context.Context, app *spinv1alpha1.SpinApp,
 
 // ConstructEnvForApp constructs the env for a spin app that runs as a k8s pod.
 // Variables are not guaranteed to stay backed by ENV.
-func ConstructEnvForApp(ctx context.Context, app *spinv1alpha1.SpinApp, listenPort int) []corev1.EnvVar {
+func ConstructEnvForApp(ctx context.Context, app *spinv1alpha1.SpinApp, listenPort int, otel *spinv1alpha1.OtelConfig) []corev1.EnvVar {
 	envs := make([]corev1.EnvVar, len(app.Spec.Variables))
+	// Adding the Spin Variables
 	for idx, variable := range app.Spec.Variables {
 		env := corev1.EnvVar{
 			// Spin Variables only allow lowercase ascii characters, `_`, and numbers.
@@ -121,6 +122,24 @@ func ConstructEnvForApp(ctx context.Context, app *spinv1alpha1.SpinApp, listenPo
 		Name:  "SPIN_HTTP_LISTEN_ADDR",
 		Value: fmt.Sprintf("0.0.0.0:%d", listenPort),
 	})
+	// Adding the OpenTelemetry params
+	if otel != nil {
+		if otel.ExporterOtlpEndpoint != "" {
+			envs = append(envs, corev1.EnvVar{Name: "OTEL_EXPORTER_OTLP_ENDPOINT", Value: otel.ExporterOtlpEndpoint})
+		}
+
+		if otel.ExporterOtlpTracesEndpoint != "" {
+			envs = append(envs, corev1.EnvVar{Name: "OTEL_EXPORTER_OTLP_TRACES_ENDPOINT", Value: otel.ExporterOtlpTracesEndpoint})
+		}
+
+		if otel.ExporterOtlpMetricsEndpoint != "" {
+			envs = append(envs, corev1.EnvVar{Name: "OTEL_EXPORTER_OTLP_METRICS_ENDPOINT", Value: otel.ExporterOtlpMetricsEndpoint})
+		}
+
+		if otel.ExporterOtlpLogsEndpoint != "" {
+			envs = append(envs, corev1.EnvVar{Name: "OTEL_EXPORTER_OTLP_LOGS_ENDPOINT", Value: otel.ExporterOtlpLogsEndpoint})
+		}
+	}
 
 	return envs
 }

internal/controller/deployment_test.go

@@ -94,6 +94,9 @@ func TestConstructEnvForApp(t *testing.T) {
 
 		value     string
 		valueFrom *corev1.EnvVarSource
+
+		expectedOtelVars map[string]string
+		otelVars         spinv1alpha1.OtelConfig
 	}{
 		{
 			name:            "simple_secret_with_static_value",
@@ -129,6 +132,21 @@ func TestConstructEnvForApp(t *testing.T) {
 				},
 			},
 		},
+		{
+			name: "otel_vars_are_properly_set",
+			otelVars: spinv1alpha1.OtelConfig{
+				ExporterOtlpEndpoint:        "http://otlp",
+				ExporterOtlpTracesEndpoint:  "http://traces",
+				ExporterOtlpMetricsEndpoint: "http://metrics",
+				ExporterOtlpLogsEndpoint:    "http://logs",
+			},
+			expectedOtelVars: map[string]string{
+				"OTEL_EXPORTER_OTLP_ENDPOINT":         "http://otlp",
+				"OTEL_EXPORTER_OTLP_TRACES_ENDPOINT":  "http://traces",
+				"OTEL_EXPORTER_OTLP_METRICS_ENDPOINT": "http://metrics",
+				"OTEL_EXPORTER_OTLP_LOGS_ENDPOINT":    "http://logs",
+			},
+		},
 	}
 
 	for _, test := range tests {
@@ -142,11 +160,28 @@ func TestConstructEnvForApp(t *testing.T) {
 				},
 			}
 
-			envs := ConstructEnvForApp(context.Background(), app, 0)
+			envs := ConstructEnvForApp(context.Background(), app, 0, &test.otelVars)
 
 			require.Equal(t, test.expectedEnvName, envs[0].Name)
 			require.Equal(t, test.value, envs[0].Value)
 			require.Equal(t, test.valueFrom, envs[0].ValueFrom)
+
+			for key, value := range test.expectedOtelVars {
+				varNotFound := true
+				for _, envVar := range envs {
+					if envVar.Name == key {
+						varNotFound = false
+						if envVar.Value != value {
+							require.Equal(t, test.value, envVar.Value)
+							break
+						}
+					}
+				}
+
+				if varNotFound {
+					require.NotContains(t, test.expectedOtelVars, key)
+				}
+			}
 		})
 	}
 }

internal/controller/spinapp_controller.go

@@ -423,7 +423,7 @@ func constructDeployment(ctx context.Context, app *spinv1alpha1.SpinApp, config
 		Requests: app.Spec.Resources.Requests,
 	}
 
-	env := ConstructEnvForApp(ctx, app, spinapp.DefaultHTTPPort)
+	env := ConstructEnvForApp(ctx, app, spinapp.DefaultHTTPPort, config.Otel)
 
 	readinessProbe, livenessProbe, err := ConstructPodHealthChecks(app)
 	if err != nil {