BackendPlugin: Change QueryData response format (#23234)

* BackendPlugin: (wip) change response format
goes with https://github.com/grafana/grafana-plugin-sdk-go/pull/109

* fix error mapping in wrapper

* latest of my sdk branch

* latest of my sdk branch

* TransformWrapper fixes

* latest of sdk branch (removes extra meta)

* add metadata in wrappers

* also set error string

* sdk: v0.35.0

pkg/plugins/datasource/wrapper/datasource_plugin_wrapper_v2.go

@@ -2,12 +2,13 @@ package wrapper
 
 import (
 	"context"
+	"fmt"
 	"time"
 
+	"github.com/grafana/grafana/pkg/components/simplejson"
 	"github.com/grafana/grafana/pkg/plugins/backendplugin"
 
 	"github.com/grafana/grafana-plugin-sdk-go/genproto/pluginv2"
-	"github.com/grafana/grafana/pkg/components/simplejson"
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/models"
 	"github.com/grafana/grafana/pkg/tsdb"
@@ -81,12 +82,24 @@ func (tw *DatasourcePluginWrapperV2) Query(ctx context.Context, ds *models.DataS
 		return nil, err
 	}
 
-	return &tsdb.Response{
-		Results: map[string]*tsdb.QueryResult{
-			"": {
-				Dataframes: pbRes.Frames,
-				Meta:       simplejson.NewFromAny(pbRes.Metadata),
-			},
-		},
-	}, nil
+	tR := &tsdb.Response{
+		Results: make(map[string]*tsdb.QueryResult, len(pbRes.Responses)),
+	}
+
+	for refID, pRes := range pbRes.Responses {
+		qr := &tsdb.QueryResult{
+			RefId:      refID,
+			Dataframes: pRes.Frames,
+		}
+		if len(pRes.JsonMeta) != 0 {
+			qr.Meta = simplejson.NewFromAny(pRes.JsonMeta)
+		}
+		if pRes.Error != "" {
+			qr.Error = fmt.Errorf(pRes.Error)
+			qr.ErrorString = pRes.Error
+		}
+		tR.Results[refID] = qr
+	}
+
+	return tR, nil
 }

pkg/plugins/transform_plugin.go

@@ -103,14 +103,25 @@ func (tw *TransformWrapper) Transform(ctx context.Context, query *tsdb.TsdbQuery
 		return nil, err
 	}
 
-	return &tsdb.Response{
-		Results: map[string]*tsdb.QueryResult{
-			"": {
-				Dataframes: pbRes.Frames,
-				Meta:       simplejson.NewFromAny(pbRes.Metadata),
-			},
-		},
-	}, nil
+	tR := &tsdb.Response{
+		Results: make(map[string]*tsdb.QueryResult, len(pbRes.Responses)),
+	}
+	for refID, res := range pbRes.Responses {
+		tRes := &tsdb.QueryResult{
+			RefId:      refID,
+			Dataframes: res.Frames,
+		}
+		if len(res.JsonMeta) != 0 {
+			tRes.Meta = simplejson.NewFromAny(res.JsonMeta)
+		}
+		if res.Error != "" {
+			tRes.Error = fmt.Errorf(res.Error)
+			tRes.ErrorString = res.Error
+		}
+		tR.Results[refID] = tRes
+	}
+
+	return tR, nil
 }
 
 type transformCallback struct {
@@ -168,18 +179,16 @@ func (s *transformCallback) QueryData(ctx context.Context, req *pluginv2.QueryDa
 	}
 	// Convert tsdb results (map) to plugin-model/datasource (slice) results.
 	// Only error, tsdb.Series, and encoded Dataframes responses are mapped.
-
-	encodedFrames := [][]byte{}
+	responses := make(map[string]*pluginv2.DataResponse, len(tsdbRes.Results))
 	for refID, res := range tsdbRes.Results {
-
+		pRes := &pluginv2.DataResponse{}
 		if res.Error != nil {
-			// TODO add Errors property to Frame
-			encodedFrames = append(encodedFrames, nil)
-			continue
+			pRes.Error = res.Error.Error()
 		}
 
 		if res.Dataframes != nil {
-			encodedFrames = append(encodedFrames, res.Dataframes...)
+			pRes.Frames = res.Dataframes
+			responses[refID] = pRes
 			continue
 		}
 
@@ -193,8 +202,18 @@ func (s *transformCallback) QueryData(ctx context.Context, req *pluginv2.QueryDa
 			if err != nil {
 				return nil, err
 			}
-			encodedFrames = append(encodedFrames, encFrame)
+			pRes.Frames = append(pRes.Frames, encFrame)
 		}
+		if res.Meta != nil {
+			b, err := res.Meta.MarshalJSON()
+			if err != nil {
+				s.logger.Error("failed to marhsal json metadata", err)
+			}
+			pRes.JsonMeta = b
+		}
+		responses[refID] = pRes
 	}
-	return &pluginv2.QueryDataResponse{Frames: encodedFrames}, nil
+	return &pluginv2.QueryDataResponse{
+		Responses: responses,
+	}, nil
 }