Resource server improvements and fixes (#90715)

* cleanup dependencies and improve list method
* Improve Resource Server API, remove unnecessary dependencies
* Reduce the API footprint of ResourceDBInterface and its implementation
* Improve LifecycleHooks to use context
* Improve testing
* reduce API size and improve code
* sqltemplate: add DialectForDriver func and improve naming
* improve lifecycle API
* many small fixes after adding more tests

pkg/storage/unified/sql/db/service.go

@@ -3,30 +3,13 @@ package db
 import (
 	"context"
 	"database/sql"
-
-	"xorm.io/xorm"
-
-	"github.com/grafana/grafana/pkg/services/sqlstore/session"
-	"github.com/grafana/grafana/pkg/setting"
 )
 
-const (
-	DriverPostgres = "postgres"
-	DriverMySQL    = "mysql"
-	DriverSQLite   = "sqlite"
-	DriverSQLite3  = "sqlite3"
-)
-
-// ResourceDBInterface provides access to a database capable of supporting the
-// Entity Server.
-type ResourceDBInterface interface {
-	Init() error
-	GetCfg() *setting.Cfg
-	GetDB() (DB, error)
-
-	// TODO: deprecate.
-	GetSession() (*session.SessionDB, error)
-	GetEngine() (*xorm.Engine, error)
+// DBProvider provides access to a SQL Database.
+type DBProvider interface {
+	// Init initializes the SQL Database, running migrations if needed. It is
+	// idempotent and thread-safe.
+	Init(context.Context) (DB, error)
 }
 
 // DB is a thin abstraction on *sql.DB to allow mocking to provide better unit