Aggregator: Add README and example query (#93351)

pkg/aggregator/README.md

@@ -0,0 +1,30 @@
+## Data Plane Aggregator
+
+### Testing queries
+
+1. `custom.ini` changes:
+```ini
+[feature_toggles]
+kubernetesAggregator = true
+dataplaneAggregator = true
+grafanaAPIServerEnsureKubectlAccess = true
+```
+
+2. start grafana:
+```bash
+make run
+```
+
+3. enable aggregation for prometheus data source:
+```bash
+export KUBECONFIG=./data/grafana-apiserver/grafana.kubeconfig
+kubectl apply -f pkg/aggregator/examples/datasource.yml --validate=false
+dataplaneservice.aggregation.grafana.app/v0alpha1.prometheus.grafana.app created
+```
+
+4. edit `pkg/aggregator/examples/datasource-query.json` and update the datasource UID to match the UID of a prometheus data source.
+
+5. execute query (replace `example` with the UID of a prometheus data source):
+```bash
+curl 'http://admin:admin@localhost:3000/apis/prometheus.grafana.app/v0alpha1/namespaces/default/connections/example/query' -X POST -d '@pkg/aggregator/examples/datasource-query.json'
+```

pkg/aggregator/apiserver/apiserver.go

@@ -152,7 +152,7 @@ func (s *GrafanaAggregator) AddDataPlaneService(dataplaneService *v0alpha1.DataP
 		return nil
 	}
 
-	proxyPath := "/apis/dataplane/" + dataplaneService.Spec.Group + "/" + dataplaneService.Spec.Version
+	proxyPath := "/apis/" + dataplaneService.Spec.Group + "/" + dataplaneService.Spec.Version
 	proxyHandler := &dataPlaneServiceHandler{
 		localDelegate:         s.delegateHandler,
 		client:                s.PluginClient,
@@ -176,7 +176,7 @@ func (s *GrafanaAggregator) AddDataPlaneService(dataplaneService *v0alpha1.DataP
 func (s *GrafanaAggregator) RemoveDataPlaneService(dataplaneServiceName string) {
 	version := v0alpha1helper.DataPlaneServiceNameToGroupVersion(dataplaneServiceName)
 
-	proxyPath := "/apis/dataplane/" + version.Group + "/" + version.Version
+	proxyPath := "/apis/" + version.Group + "/" + version.Version
 	s.GenericAPIServer.Handler.NonGoRestfulMux.Unregister(proxyPath)
 	s.GenericAPIServer.Handler.NonGoRestfulMux.Unregister(proxyPath + "/")
 	delete(s.proxyHandlers, dataplaneServiceName)
@@ -190,7 +190,7 @@ func (s *GrafanaAggregator) RemoveDataPlaneService(dataplaneServiceName string)
 		return
 	}
 	delete(s.handledGroupVersions, version.Group)
-	groupPath := "/apis/dataplane/" + version.Group
+	groupPath := "/apis/" + version.Group
 	s.GenericAPIServer.Handler.NonGoRestfulMux.Unregister(groupPath)
 	s.GenericAPIServer.Handler.NonGoRestfulMux.Unregister(groupPath + "/")
 }

pkg/aggregator/apiserver/plugin/query.go

@@ -47,7 +47,7 @@ func (h *PluginHandler) QueryDataHandler() http.HandlerFunc {
 		// the datasource type in the query body should match the plugin ID
 		if dsRef.Type != dsType {
 			err := errors.New("invalid datasource type")
-			klog.ErrorS(err, "type", dsType, "ref.Type", dsRef.Type)
+			klog.ErrorS(err, err.Error(), "dsType", dsType, "refType", dsRef.Type)
 			responder.Error(w, req, err)
 			return
 		}
@@ -55,7 +55,7 @@ func (h *PluginHandler) QueryDataHandler() http.HandlerFunc {
 		// the UID in the query body should match the UID in the URL
 		if dsRef.UID != dsUID {
 			err := errors.New("invalid datasource UID")
-			klog.ErrorS(err, "path", dsUID, "ref.UID", dsRef.UID)
+			klog.ErrorS(err, err.Error(), "path", dsUID, "refUID", dsRef.UID)
 			responder.Error(w, req, err)
 			return
 		}

pkg/aggregator/examples/datasource-query.json

@@ -0,0 +1,26 @@
+{
+    "queries": [
+        {
+            "refId": "A",
+            "expr": "grafana_environment_info{}",
+            "range": true,
+            "datasource": {
+                "type": "prometheus",
+                "uid": "example"
+            },
+            "editorMode": "code",
+            "legendFormat": "__auto",
+            "instant": false,
+            "exemplar": false,
+            "utcOffsetSec": 0,
+            "scopes": [],
+            "adhocFilters": [],
+            "interval": "",
+            "datasourceId": 2,
+            "intervalMs": 15000,
+            "maxDataPoints": 969
+        }
+    ],
+    "from": "now-1m",
+    "to": "now"
+}

pkg/aggregator/examples/datasource.yml

@@ -3,6 +3,8 @@ kind: DataPlaneService
 metadata:
   name: v0alpha1.prometheus.grafana.app
 spec:
+  pluginID: prometheus
+  pluginType: datasource
   group: prometheus.grafana.app
   version: v0alpha1
   services: