Enhance OutputSpec and Service configurations by adding support for URL path suffixes

api/v1alpha1/output_types.go

@@ -36,12 +36,12 @@ type OutputSpec struct {
 	// +optional
 	Service *OutputServiceSpec `json:"service,omitempty"`
 	// ServiceRef references a Kubernetes Service to use as the output address.
-	// Supported for: nats, jetstream, kafka outputs.
+	// Supported for: nats, jetstream, kafka, remote_write, influxdb outputs.
 	// The service address will be resolved and injected into the output config.
 	// +optional
 	ServiceRef *ServiceReference `json:"serviceRef,omitempty"`
 	// ServiceSelector selects Kubernetes Services by labels to use as output addresses.
-	// Supported for: nats, jetstream, kafka outputs.
+	// Supported for: nats, jetstream, kafka, remote_write, influxdb outputs.
 	// All matching service addresses will be resolved and injected into the output config.
 	// +optional
 	ServiceSelector *ServiceSelector `json:"serviceSelector,omitempty"`
@@ -58,6 +58,13 @@ type ServiceReference struct {
 	// If not specified, the first port of the service is used.
 	// +optional
 	Port string `json:"port,omitempty"`
+	// URL is an optional path suffix appended after the resolved service address
+	// (scheme, host, and port). A leading slash on the value is optional; the
+	// operator joins the base and suffix with a single '/'. Use this for HTTP(S)
+	// outputs such as prometheus_write (for example api/v1/write or api/v1/push)
+	// or influxdb instead of putting the full URL in config.
+	// +optional
+	URL string `json:"url,omitempty"`
 }
 
 // ServiceSelector selects Services by labels
@@ -71,6 +78,10 @@ type ServiceSelector struct {
 	// If not specified, the first port of the service is used.
 	// +optional
 	Port string `json:"port,omitempty"`
+	// URL is an optional path suffix appended after each resolved service address.
+	// Same semantics as ServiceReference.url (see ServiceReference).
+	// +optional
+	URL string `json:"url,omitempty"`
 }
 
 // OutputServiceSpec defines the service configuration for outputs that expose an endpoint

config/crd/bases/operator.gnmic.dev_outputs.yaml

@@ -74,7 +74,7 @@ spec:
               serviceRef:
                 description: |-
                   ServiceRef references a Kubernetes Service to use as the output address.
-                  Supported for: nats, jetstream, kafka outputs.
+                  Supported for: nats, jetstream, kafka, remote_write, influxdb outputs.
                   The service address will be resolved and injected into the output config.
                 properties:
                   name:
@@ -89,13 +89,21 @@ spec:
                       Port is the name or number of the port to use.
                       If not specified, the first port of the service is used.
                     type: string
+                  url:
+                    description: |-
+                      URL is an optional path suffix appended after the resolved service address
+                      (scheme, host, and port). A leading slash on the value is optional; the
+                      operator joins the base and suffix with a single '/'. Use this for HTTP(S)
+                      outputs such as prometheus_write (for example api/v1/write or api/v1/push)
+                      or influxdb instead of putting the full URL in config.
+                    type: string
                 required:
                 - name
                 type: object
               serviceSelector:
                 description: |-
                   ServiceSelector selects Kubernetes Services by labels to use as output addresses.
-                  Supported for: nats, jetstream, kafka outputs.
+                  Supported for: nats, jetstream, kafka, remote_write, influxdb outputs.
                   All matching service addresses will be resolved and injected into the output config.
                 properties:
                   matchLabels:
@@ -113,6 +121,11 @@ spec:
                       Port is the name or number of the port to use.
                       If not specified, the first port of the service is used.
                     type: string
+                  url:
+                    description: |-
+                      URL is an optional path suffix appended after each resolved service address.
+                      Same semantics as ServiceReference.url (see ServiceReference).
+                    type: string
                 required:
                 - matchLabels
                 type: object

docs/content/docs/user-guide/output.md

@@ -51,6 +51,7 @@ Defines the output address or URL as a service reference.
 | `name` | string | Yes | Name of the Kubernetes Service |
 | `namespace` | string | No | Namespace of the Service (defaults to Output's namespace) |
 | `port` | string | No | Port name or number (defaults to first port) |
+| `url` | string | No | Path suffix appended after the resolved `scheme://host:port` (optional leading slash). Use for HTTP(S) outputs such as `prometheus_write` or `influxdb` (for example `api/v1/write` or `api/v1/push`) so you do not need the full URL in `config`. |
 
 ### ServiceSelector
 
@@ -61,6 +62,7 @@ Defines the output address or URL as a service selector.
 | `matchLabels` | map[string]string | Yes | Labels to match services |
 | `namespace` | string | No | Namespace to search (defaults to Output's namespace) |
 | `port` | string | No | Port name or number (defaults to first port) |
+| `url` | string | No | Path suffix appended after each resolved address; same meaning as `serviceRef.url`. |
 
 - It is recommended to label outputs for flexible selection when building Pipelines.
 
@@ -208,6 +210,19 @@ spec:
 
 The operator resolves the service and constructs the URL as `http://prometheus-server.{namespace}.svc.cluster.local:9090`.
 
+To set the HTTP path without duplicating the host in `config`, use `serviceRef.url` (for example Grafana Mimir at `/api/v1/push`):
+
+```yaml
+spec:
+  type: prometheus_write
+  serviceRef:
+    name: mimir-distributor
+    port: http
+    url: api/v1/push
+  config:
+    timeout: 10s
+```
+
 ### Using Service Selector
 
 Discover multiple Kafka brokers using labels:
@@ -483,6 +498,10 @@ For outputs that connect to external systems (NATS, Kafka, InfluxDB, Prometheus
 | **Result** | Single address | Multiple addresses (comma-separated) |
 | **Cross-namespace** | Yes (specify namespace) | Yes (specify namespace) |
 
+### Path suffix (`url`)
+
+For `serviceRef` and `serviceSelector`, optional field `url` is appended after the resolved address (scheme, DNS name, and port). It is most useful for `prometheus_write` and `influxdb`, where gNMIc expects a full URL: you can rely on service discovery for the host and port and set only the path here (for example `api/v1/write` for Prometheus or `api/v1/push` for Mimir). Leading slashes are optional.
+
 1. The operator watches for Output resources
 2. During reconciliation, it resolves the referenced Service(s)
 3. Addresses are formatted with the appropriate scheme (`nats://`)

internal/controller/cluster_controller.go

@@ -2334,6 +2334,11 @@ func (r *ClusterReconciler) resolveOutputServiceAddresses(ctx context.Context, o
 		// use cluster DNS name for the service
 		host := fmt.Sprintf("%s.%s.svc.cluster.local", svc.Name, svc.Namespace)
 		addr := gnmic.FormatServiceAddress(spec, host, port)
+		if spec.ServiceRef.URL != "" {
+			url := strings.TrimPrefix(spec.ServiceRef.URL, "/")
+			addr = strings.TrimSuffix(addr, "/")
+			addr = fmt.Sprintf("%s/%s", addr, url)
+		}
 		resolved = append(resolved, addr)
 	}
 
@@ -2369,6 +2374,11 @@ func (r *ClusterReconciler) resolveOutputServiceAddresses(ctx context.Context, o
 			// use cluster DNS name for the service
 			host := fmt.Sprintf("%s.%s.svc.cluster.local", svc.Name, svc.Namespace)
 			addr := gnmic.FormatServiceAddress(spec, host, port)
+			if spec.ServiceSelector.URL != "" {
+				url := strings.TrimPrefix(spec.ServiceSelector.URL, "/")
+				addr = strings.TrimSuffix(addr, "/")
+				addr = fmt.Sprintf("%s/%s", addr, url)
+			}
 			resolved = append(resolved, addr)
 		}
 	}

internal/gnmic/output.go

@@ -47,6 +47,8 @@ type outputConfigOptions struct {
 	ResolvedAddresses []string
 	// TLS options to inject into the output config
 	TLS *TLSOptions
+	// URL to append to discovered service addresses
+	URL string
 }
 
 type TLSOptions struct {
@@ -89,6 +91,7 @@ func buildOutputConfig(spec *gnmicv1alpha1.OutputSpec, options *outputConfigOpti
 				config["address"] = strings.Join(options.ResolvedAddresses, ",")
 			case PrometheusWriteOutputType:
 				config["url"] = strings.Join(options.ResolvedAddresses, ",")
+
 			case InfluxDBOutputType:
 				config["url"] = strings.Join(options.ResolvedAddresses, ",")
 			}

internal/gnmic/plan.go

@@ -60,7 +60,6 @@ type resourceRelationship struct {
 
 // NewPlanBuilder creates a new PlanBuilder
 func NewPlanBuilder(clusterName string, credsFetcher CredentialsFetcher) *PlanBuilder {
-
 	return &PlanBuilder{
 		clusterName:  clusterName,
 		pipelines:    make(map[string]*PipelineData),