Plugins: Core plugins register via backend factory provider (#43171)

* refactoring store interface and init flow

* fix import

* fix linter

* refactor resource calling

* load with class

* re-order args

* fix tests

* fix linter

* remove old creator

* add custom config struct

* fix some tests

* cleanup

* fix

* tackle plugins

* fix linter

* refactor and fix test

* add connect failure error

* add fix for azure, cloud monitoring and test data

* restructure

* remove unused err

* add fake tracer for test

* fix grafana ds plugin

pkg/tsdb/mysql/mysql.go

@@ -20,14 +20,11 @@ import (
 	"github.com/grafana/grafana-plugin-sdk-go/data/sqlutil"
 	"github.com/grafana/grafana/pkg/infra/httpclient"
 	"github.com/grafana/grafana/pkg/infra/log"
-	"github.com/grafana/grafana/pkg/plugins"
-	"github.com/grafana/grafana/pkg/plugins/backendplugin/coreplugin"
 	"github.com/grafana/grafana/pkg/setting"
 	"github.com/grafana/grafana/pkg/tsdb/sqleng"
 )
 
 const (
-	pluginID        = "mysql"
 	dateFormat      = "2006-01-02"
 	dateTimeFormat1 = "2006-01-02 15:04:05"
 	dateTimeFormat2 = "2006-01-02T15:04:05Z"
@@ -44,19 +41,10 @@ func characterEscape(s string, escapeChar string) string {
 	return strings.ReplaceAll(s, escapeChar, url.QueryEscape(escapeChar))
 }
 
-func ProvideService(cfg *setting.Cfg, pluginStore plugins.Store, httpClientProvider httpclient.Provider) (*Service, error) {
-	s := &Service{
+func ProvideService(cfg *setting.Cfg, httpClientProvider httpclient.Provider) *Service {
+	return &Service{
 		im: datasource.NewInstanceManager(newInstanceSettings(cfg, httpClientProvider)),
 	}
-	factory := coreplugin.New(backend.ServeOpts{
-		QueryDataHandler: s,
-	})
-
-	resolver := plugins.CoreDataSourcePathResolver(cfg, pluginID)
-	if err := pluginStore.AddWithFactory(context.Background(), pluginID, factory, resolver); err != nil {
-		logger.Error("Failed to register plugin", "error", err)
-	}
-	return s, nil
 }
 
 func newInstanceSettings(cfg *setting.Cfg, httpClientProvider httpclient.Provider) datasource.InstanceFactoryFunc {