Add limitador tracing-endpoint command

README.md

@@ -42,6 +42,7 @@ spec:
 * [Storage Options](./doc/storage.md)
 * [Rate Limit Headers](./doc/rate-limit-headers.md)
 * [Logging](./doc/logging.md)
+* [Tracing](./doc/tracing.md)
 
 ## Contributing
 

api/v1alpha1/limitador_types.go

@@ -86,6 +86,9 @@ type LimitadorSpec struct {
 	// +optional
 	Telemetry *Telemetry `json:"telemetry,omitempty"`
 
+	// +optional
+	Tracing *Tracing `json:"tracing,omitempty"`
+
 	// +optional
 	Limits []RateLimit `json:"limits,omitempty"`
 
@@ -324,6 +327,10 @@ type Ports struct {
 	GRPC int32 `json:"grpc,omitempty"`
 }
 
+type Tracing struct {
+	Endpoint string `json:"endpoint"`
+}
+
 type PodDisruptionBudgetType struct {
 	// An eviction is allowed if at most "maxUnavailable" limitador pods
 	// are unavailable after the eviction, i.e. even in absence of

bundle/manifests/limitador-operator.clusterserviceversion.yaml

@@ -37,7 +37,7 @@ metadata:
     capabilities: Basic Install
     categories: Integration & Delivery
     containerImage: quay.io/kuadrant/limitador-operator:latest
-    createdAt: "2024-04-04T14:34:19Z"
+    createdAt: "2024-04-15T10:48:14Z"
     operators.operatorframework.io/builder: operator-sdk-v1.32.0
     operators.operatorframework.io/project_layout: go.kubebuilder.io/v3
     repository: https://github.com/Kuadrant/limitador-operator

bundle/manifests/limitador.kuadrant.io_limitadors.yaml

@@ -1083,6 +1083,13 @@ spec:
                 - basic
                 - exhaustive
                 type: string
+              tracing:
+                properties:
+                  endpoint:
+                    type: string
+                required:
+                - endpoint
+                type: object
               verbosity:
                 description: Sets the level of verbosity
                 maximum: 4

config/crd/bases/limitador.kuadrant.io_limitadors.yaml

@@ -1084,6 +1084,13 @@ spec:
                 - basic
                 - exhaustive
                 type: string
+              tracing:
+                properties:
+                  endpoint:
+                    type: string
+                required:
+                - endpoint
+                type: object
               verbosity:
                 description: Sets the level of verbosity
                 maximum: 4

doc/tracing.md

@@ -0,0 +1,30 @@
+# Tracing
+
+Limitador offers distributed tracing enablement using the `.spec.tracing` CR configuration:
+
+```yaml
+---
+apiVersion: limitador.kuadrant.io/v1alpha1
+kind: Limitador
+metadata:
+  name: limitador-sample
+spec:
+  listener:
+    http:
+      port: 8080
+    grpc:
+      port: 8081
+  limits:
+    - conditions: ["get_toy == 'yes'"]
+      max_value: 2
+      namespace: toystore-app
+      seconds: 30
+      variables: []
+  verbosity: 3
+  tracing:
+    endpoint: rpc://my-otlp-collector:4317
+```
+
+Currently limitador only supports collectors using the OpenTelemetry Protocol with TLS disabled. The `endpoint` configuration option should contain the scheme, host and port of the service. The quantity and level of the information provided by the spans is configured via the `verbosity` argument.
+
+![Limitador tracing example](https://github.com/Kuadrant/limitador-operator/assets/6575004/7bdc7c17-37a5-4dfe-ac56-432efa1070c4)

pkg/limitador/deployment_options.go

@@ -45,6 +45,10 @@ func DeploymentCommand(limObj *limitadorv1alpha1.Limitador, storageOptions Deplo
 		command = append(command, "--limit-name-in-labels")
 	}
 
+	if limObj.Spec.Tracing != nil {
+		command = append(command, "--tracing-endpoint", limObj.Spec.Tracing.Endpoint)
+	}
+
 	if limObj.Spec.Verbosity != nil {
 		command = append(command, fmt.Sprintf("-%s", strings.Repeat("v", int(*limObj.Spec.Verbosity))))
 	}

pkg/limitador/deployment_options_test.go

@@ -107,6 +107,26 @@ func TestDeploymentCommand(t *testing.T) {
 			})
 		}
 	})
+
+	t.Run("command from tracing endpoint appended", func(subT *testing.T) {
+		testEndpoint := "rpc://tracing-endpoint:4317"
+		limObj := basicLimitador()
+		limObj.Spec.Tracing = &limitadorv1alpha1.Tracing{
+			Endpoint: testEndpoint,
+		}
+		command := DeploymentCommand(limObj, DeploymentStorageOptions{})
+		assert.DeepEqual(subT, command,
+			[]string{
+				"limitador-server",
+				"--tracing-endpoint",
+				testEndpoint,
+				"--http-port",
+				strconv.Itoa(int(limitadorv1alpha1.DefaultServiceHTTPPort)),
+				"--rls-port",
+				strconv.Itoa(int(limitadorv1alpha1.DefaultServiceGRPCPort)),
+				"/home/limitador/etc/limitador-config.yaml",
+			})
+	})
 }
 
 func TestDeploymentVolumeMounts(t *testing.T) {