K8s: Expose testdata connection as an api-server (dev mode only) (#79726)

pkg/registry/apis/datasource/sub_query.go

@@ -0,0 +1,103 @@
+package datasource
+
+import (
+	"context"
+	"encoding/json"
+	"io"
+	"net/http"
+	"time"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apiserver/pkg/registry/rest"
+)
+
+type subQueryREST struct {
+	builder *DataSourceAPIBuilder
+}
+
+var _ = rest.Connecter(&subQueryREST{})
+
+func (r *subQueryREST) New() runtime.Object {
+	return &metav1.Status{}
+}
+
+func (r *subQueryREST) Destroy() {
+}
+
+func (r *subQueryREST) ConnectMethods() []string {
+	return []string{"POST", "GET"}
+}
+
+func (r *subQueryREST) NewConnectOptions() (runtime.Object, bool, string) {
+	return nil, false, ""
+}
+
+func (r *subQueryREST) readQueries(req *http.Request) ([]backend.DataQuery, error) {
+	// Simple URL to JSON mapping
+	if req.Method == http.MethodGet {
+		body := make(map[string]any, 0)
+		for k, v := range req.URL.Query() {
+			switch len(v) {
+			case 0:
+				body[k] = true
+			case 1:
+				body[k] = v[0] // TODO, convert numbers
+			default:
+				body[k] = v // TODO, convert numbers
+			}
+		}
+
+		var err error
+		dq := backend.DataQuery{
+			RefID: "A",
+			TimeRange: backend.TimeRange{
+				From: time.Now().Add(-1 * time.Hour), // last hour
+				To:   time.Now(),
+			},
+			MaxDataPoints: 1000,
+			Interval:      time.Second * 10,
+		}
+		dq.JSON, err = json.Marshal(body)
+		return []backend.DataQuery{dq}, err
+	}
+
+	body, err := io.ReadAll(req.Body)
+	if err != nil {
+		return nil, err
+	}
+	return readQueries(body)
+}
+
+func (r *subQueryREST) Connect(ctx context.Context, name string, opts runtime.Object, responder rest.Responder) (http.Handler, error) {
+	pluginCtx, err := r.builder.getDataSourcePluginContext(ctx, name)
+	if err != nil {
+		return nil, err
+	}
+
+	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
+		queries, err := r.readQueries(req)
+		if err != nil {
+			responder.Error(err)
+			return
+		}
+
+		queryResponse, err := r.builder.client.QueryData(ctx, &backend.QueryDataRequest{
+			PluginContext: *pluginCtx,
+			Queries:       queries,
+			//  Headers: // from context
+		})
+		if err != nil {
+			return
+		}
+
+		jsonRsp, err := json.Marshal(queryResponse)
+		if err != nil {
+			responder.Error(err)
+			return
+		}
+		w.WriteHeader(200)
+		_, _ = w.Write(jsonRsp)
+	}), nil
+}