InfluxDB: SQL Support (#72167)

* Add influxdbSqlSupport feature toggle

* Add SQL option to the config page

* Add SQL backend

* Add metadata support in config page

* Implement unified querying

* Fix healthcheck query

* fsql tests

* secure grpc by default

* code cleanup

* Query handing for sql mode

* Implement a placeholder sql editor

* Fix query language dropdown

* go mod updates

* make lint-go

* more make lint-go

* remove unused runQuery

* switch statements with default case

* linting again

pkg/tsdb/influxdb/influxdb.go

@@ -14,10 +14,12 @@ import (
 	"github.com/grafana/grafana-plugin-sdk-go/backend/datasource"
 	"github.com/grafana/grafana-plugin-sdk-go/backend/instancemgmt"
 
+	"github.com/grafana/grafana/pkg/tsdb/influxdb/flux"
+	"github.com/grafana/grafana/pkg/tsdb/influxdb/fsql"
+
 	"github.com/grafana/grafana/pkg/infra/httpclient"
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/setting"
-	"github.com/grafana/grafana/pkg/tsdb/influxdb/flux"
 	"github.com/grafana/grafana/pkg/tsdb/influxdb/models"
 )
 
@@ -57,22 +59,27 @@ func newInstanceSettings(httpClientProvider httpclient.Provider) datasource.Inst
 		if err != nil {
 			return nil, fmt.Errorf("error reading settings: %w", err)
 		}
+
 		httpMode := jsonData.HTTPMode
 		if httpMode == "" {
 			httpMode = "GET"
 		}
+
 		maxSeries := jsonData.MaxSeries
 		if maxSeries == 0 {
 			maxSeries = 1000
 		}
+
 		version := jsonData.Version
 		if version == "" {
 			version = influxVersionInfluxQL
 		}
+
 		database := jsonData.DbName
 		if database == "" {
 			database = settings.Database
 		}
+
 		model := &models.DatasourceInfo{
 			HTTPClient:    client,
 			URL:           settings.URL,
@@ -82,7 +89,9 @@ func newInstanceSettings(httpClientProvider httpclient.Provider) datasource.Inst
 			TimeInterval:  jsonData.TimeInterval,
 			DefaultBucket: jsonData.DefaultBucket,
 			Organization:  jsonData.Organization,
+			Metadata:      jsonData.Metadata,
 			MaxSeries:     maxSeries,
+			SecureGrpc:    true,
 			Token:         settings.DecryptedSecureJSONData["token"],
 		}
 		return model, nil
@@ -98,9 +107,12 @@ func (s *Service) QueryData(ctx context.Context, req *backend.QueryDataRequest)
 		return nil, err
 	}
 	version := dsInfo.Version
-	if version == "Flux" {
+	if version == influxVersionFlux {
 		return flux.Query(ctx, dsInfo, *req)
 	}
+	if version == influxVersionSQL {
+		return fsql.Query(ctx, dsInfo, *req)
+	}
 
 	logger.Debug("Making a non-Flux type query")