datasources: querier: handle the grafana-ds (#103980)

* datasources: querier: handle the grafana-ds

* updated dependencies

pkg/registry/apis/query/client/plugin.go

@@ -19,9 +19,11 @@ import (
 	"github.com/grafana/grafana/pkg/registry/apis/query/clientapi"
 	"github.com/grafana/grafana/pkg/services/accesscontrol"
 	"github.com/grafana/grafana/pkg/services/datasources"
+	"github.com/grafana/grafana/pkg/services/pluginsintegration/adapters"
 	"github.com/grafana/grafana/pkg/services/pluginsintegration/plugincontext"
 	"github.com/grafana/grafana/pkg/services/pluginsintegration/pluginstore"
 	"github.com/grafana/grafana/pkg/setting"
+	"github.com/grafana/grafana/pkg/tsdb/grafanads"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 )
 
@@ -90,6 +92,23 @@ func (d *pluginClient) CanQueryDataSource(ctx context.Context, uid string) (bool
 	return d.ac.Evaluate(ctx, user, evaluate)
 }
 
+// this handles the special `--grafana--` data source
+func getGrafanaDataSourceSettings(ctx context.Context) (*backend.DataSourceInstanceSettings, error) {
+	user, err := identity.GetRequester(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	ds := grafanads.DataSourceModel(user.GetOrgID())
+
+	decryptFunc := func(ds *datasources.DataSource) (map[string]string, error) {
+		// we do not need to handle any secrets
+		return nil, nil
+	}
+
+	return adapters.ModelToInstanceSettings(ds, decryptFunc)
+}
+
 // ExecuteQueryData implements QueryHelper.
 func (d *pluginClient) QueryData(ctx context.Context, req data.QueryDataRequest) (*backend.QueryDataResponse, error) {
 	queries, dsRef, err := data.ToDataSourceQueries(req)
@@ -109,8 +128,16 @@ func (d *pluginClient) QueryData(ctx context.Context, req data.QueryDataRequest)
 		return nil, k8sForbiddenError
 	}
 
-	// NOTE: this depends on uid unique across datasources
-	settings, err := d.pCtxProvider.GetDataSourceInstanceSettings(ctx, dsRef.UID)
+	var settings *backend.DataSourceInstanceSettings
+
+	// we need to special-case the "--grafana--" data source
+	if dsRef.UID == grafanads.DatasourceUID {
+		settings, err = getGrafanaDataSourceSettings(ctx)
+	} else {
+		// NOTE: this depends on uid unique across datasources
+		settings, err = d.pCtxProvider.GetDataSourceInstanceSettings(ctx, dsRef.UID)
+	}
+
 	if err != nil {
 		// there is no better way to differentiate between plugin-not-found and other-error
 		if errors.Is(err, datasources.ErrDataSourceNotFound) {

pkg/registry/apis/query/parser.go

@@ -237,6 +237,18 @@ func (p *queryParser) getValidDataSourceRef(ctx context.Context, ds *data.DataSo
 		}
 		return p.legacy.GetDataSourceFromDeprecatedFields(ctx, "", id)
 	}
+
+	// we need to special-case the "grafana" data source
+	if ds.UID == "grafana" {
+		return &data.DataSourceRef{
+			// it does not really matter what `type` we set here,
+			// we will always detect this case by `uid` later.
+			// here we go with what the data source's plugin.json says.
+			Type: "grafana",
+			UID:  "grafana",
+		}, nil
+	}
+
 	if ds.Type == "" {
 		if ds.UID == "" {
 			return nil, fmt.Errorf("missing name/uid in data source reference")

pkg/registry/apis/query/parser_test.go

@@ -3,6 +3,7 @@ package query
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"os"
 	"path"
@@ -200,6 +201,59 @@ func TestSqlInputs(t *testing.T) {
 	require.Equal(t, parsedRequestInfo.SqlInputs["B"], struct{}{})
 }
 
+func TestGrafanaDS(t *testing.T) {
+	ctx := context.Background()
+	parser := newQueryParser(expr.NewExpressionQueryReader(featuremgmt.WithFeatures()),
+		&noLegacyRetriever{}, tracing.InitializeTracerForTest(), log.NewNopLogger())
+
+	t.Run("grafana ds without type", func(t *testing.T) {
+		parsed, err := parser.parseRequest(ctx, &query.QueryDataRequest{
+			QueryDataRequest: data.QueryDataRequest{
+				Queries: []data.DataQuery{{
+					CommonQueryProperties: data.CommonQueryProperties{
+						RefID: "A",
+						Datasource: &data.DataSourceRef{
+							UID: "grafana",
+						},
+					},
+				}},
+			},
+		})
+		require.NoError(t, err)
+		require.Len(t, parsed.Requests, 1)
+		require.Equal(t, "grafana", parsed.Requests[0].PluginId)
+		require.Equal(t, "grafana", parsed.Requests[0].UID)
+	})
+
+	t.Run("grafana ds with different type", func(t *testing.T) {
+		parsed, err := parser.parseRequest(ctx, &query.QueryDataRequest{
+			QueryDataRequest: data.QueryDataRequest{
+				Queries: []data.DataQuery{{
+					CommonQueryProperties: data.CommonQueryProperties{
+						RefID: "A",
+						Datasource: &data.DataSourceRef{
+							UID:  "grafana",
+							Type: "datasource",
+						},
+					},
+				}},
+			},
+		})
+		require.NoError(t, err)
+		require.Len(t, parsed.Requests, 1)
+		require.Equal(t, "grafana", parsed.Requests[0].PluginId)
+		require.Equal(t, "grafana", parsed.Requests[0].UID)
+	})
+}
+
+type noLegacyRetriever struct{}
+
+var errNoLegacy = errors.New("legacy dds retriever reached, it should not")
+
+func (s *noLegacyRetriever) GetDataSourceFromDeprecatedFields(ctx context.Context, name string, id int64) (*data.DataSourceRef, error) {
+	return nil, errNoLegacy
+}
+
 type legacyDataSourceRetriever struct{}
 
 func (s *legacyDataSourceRetriever) GetDataSourceFromDeprecatedFields(ctx context.Context, name string, id int64) (*data.DataSourceRef, error) {