refactor replCfg to look more like plugins/plugin config (#91142)

* refactor replCfg to look more like plugins/plugin config
* validateReplicaConfigs must handle inconsistencies in type names due to the WithHooks suffix

pkg/services/sqlstore/database_config.go

@@ -236,7 +236,7 @@ func buildExtraConnectionString(sep rune, urlQueryParams map[string][]string) st
 	return sb.String()
 }
 
-func validateReplicaConfigs(primary *DatabaseConfig, cfgs []*DatabaseConfig) error {
+func validateReplicaConfigs(primary *DatabaseConfig, cfgs []DatabaseConfig) error {
 	if cfgs == nil {
 		return errors.New("cfg cannot be nil")
 	}
@@ -256,8 +256,9 @@ func validateReplicaConfigs(primary *DatabaseConfig, cfgs []*DatabaseConfig) err
 	}
 
 	// Verify that every database is the same type and version, and that it matches the primary database.
+	// The database Yype may include a "withHooks" suffix, which is used to differentiate drivers for instrumentation and ignored for the purpose of this check.
 	for _, cfg := range cfgs {
-		if cfg.Type != primary.Type {
+		if databaseDriverFromName(cfg.Type) != databaseDriverFromName(primary.Type) {
 			result = errors.Join(result, fmt.Errorf("the replicas must have the same database type as the primary database (%s != %s)", primary.Type, cfg.Type))
 			break // Only need to report this once
 		}
@@ -265,3 +266,19 @@ func validateReplicaConfigs(primary *DatabaseConfig, cfgs []*DatabaseConfig) err
 
 	return result
 }
+
+// databaseDriverFromName strips any suffixes from the driver type that are not relevant to the database driver.
+// This is used to remove the "WithHooks" or "ReplWithHooks" suffixes which are used to differentiate drivers for instrumentation.
+func databaseDriverFromName(driverTy string) string {
+	if strings.HasPrefix(driverTy, migrator.MySQL) {
+		return migrator.MySQL
+	}
+	if strings.HasPrefix(driverTy, migrator.Postgres) {
+		return migrator.Postgres
+	}
+	if strings.HasPrefix(driverTy, migrator.SQLite) {
+		return migrator.SQLite
+	}
+	// default
+	return driverTy
+}

pkg/services/sqlstore/database_config_test.go

@@ -237,6 +237,22 @@ func TestValidateReplicaConfigs(t *testing.T) {
 		require.NoError(t, err)
 	})
 
+	t.Run("valid but awkward config", func(t *testing.T) {
+		inicfg, err := ini.Load([]byte(testReplCfg))
+		require.NoError(t, err)
+		cfg, err := setting.NewCfgFromINIFile(inicfg)
+		require.NoError(t, err)
+
+		dbCfgs, err := NewRODatabaseConfigs(cfg, nil)
+		require.NoError(t, err)
+
+		// The primary is mysql, but the replicas are mysqlWithHooks. This can
+		// occur when some but not all the replicas (or primary) have
+		// instrument_queries enabled
+		err = validateReplicaConfigs(&DatabaseConfig{Type: "mysqlWithHooks"}, dbCfgs)
+		require.NoError(t, err)
+	})
+
 	t.Run("invalid config: primary database type mismatch", func(t *testing.T) {
 		// valid repl config, the issue is that the primary has a different type
 		inicfg, err := ini.Load([]byte(testReplCfg))
@@ -284,9 +300,15 @@ name = grafana
 user = grafana
 password = password
 host = 127.0.0.1:3306
-[database_replicas.one] =
+[database_replica.one]
+name = grafana
+user = grafana
+password = password
 type = mysql
 host = 127.0.0.1:3306
-[database_replicas.two] =
+[database_replica.two]
+name = grafana
+user = grafana
+password = password
 type = postgres
 host = 127.0.0.1:3308`

pkg/services/sqlstore/replstore.go

@@ -99,7 +99,7 @@ func ProvideServiceWithReadReplica(primary *SQLStore, cfg *setting.Cfg,
 			replCfg.Type = WrapDatabaseReplDriverWithHooks(replCfg.Type, uint(i), tracer)
 		}
 
-		s, err := newReadOnlySQLStore(cfg, replCfg, features, bus, tracer)
+		s, err := newReadOnlySQLStore(cfg, &replCfg, features, bus, tracer)
 		if err != nil {
 			return nil, err
 		}
@@ -190,13 +190,13 @@ func (ss *SQLStore) initReadOnlyEngine(engine *xorm.Engine) error {
 }
 
 // NewRODatabaseConfig creates a new read-only database configuration.
-func NewRODatabaseConfigs(cfg *setting.Cfg, features featuremgmt.FeatureToggles) ([]*DatabaseConfig, error) {
+func NewRODatabaseConfigs(cfg *setting.Cfg, features featuremgmt.FeatureToggles) ([]DatabaseConfig, error) {
 	if cfg == nil {
 		return nil, errors.New("cfg cannot be nil")
 	}
 
-	// if only one replica is configured in the database_replicas section, use it as the default
-	defaultReplCfg := &DatabaseConfig{}
+	// If one replica is configured in the database_replicas section, use it as the default
+	defaultReplCfg := DatabaseConfig{}
 	if err := defaultReplCfg.readConfigSection(cfg, "database_replicas"); err != nil {
 		return nil, err
 	}
@@ -204,13 +204,13 @@ func NewRODatabaseConfigs(cfg *setting.Cfg, features featuremgmt.FeatureToggles)
 	if err != nil {
 		return nil, err
 	}
-	ret := []*DatabaseConfig{defaultReplCfg}
+	ret := []DatabaseConfig{defaultReplCfg}
 
-	// Check for additional replicas as children of the database_replicas section (e.g. database_replicas.one, database_replicas.cheetara)
-	repls := cfg.Raw.Section("database_replicas")
+	// Check for individual replicas in the database_replica section (e.g. database_replica.one, database_replica.cheetara)
+	repls := cfg.Raw.Section("database_replica")
 	if len(repls.ChildSections()) > 0 {
 		for _, sec := range repls.ChildSections() {
-			replCfg := &DatabaseConfig{}
+			replCfg := DatabaseConfig{}
 			if err := replCfg.parseConfigIni(sec); err != nil {
 				return nil, err
 			}

pkg/services/sqlstore/replstore_test.go

@@ -40,11 +40,11 @@ func TestNewRODatabaseConfig(t *testing.T) {
 
 		dbCfgs, err := NewRODatabaseConfigs(cfg, nil)
 		require.NoError(t, err)
+		require.Len(t, dbCfgs, 3)
 
 		var connStr = func(port int) string {
 			return fmt.Sprintf("grafana:password@tcp(127.0.0.1:%d)/grafana?collation=utf8mb4_unicode_ci&allowNativePasswords=true&clientFoundRows=true", port)
 		}
-
 		for i, c := range dbCfgs {
 			if !cmp.Equal(c.ConnectionString, connStr(i+3306)) {
 				t.Errorf("wrong result for connection string %d.\nGot: %s,\nWant: %s", i, c.ConnectionString, connStr(i+3306))
@@ -60,7 +60,15 @@ name = grafana
 user = grafana
 password = password
 host = 127.0.0.1:3306
-[database_replicas.one] =
+[database_replica.one]
 host = 127.0.0.1:3307
-[database_replicas.two] =
-host = 127.0.0.1:3308`
+type = mysql
+name = grafana
+user = grafana
+password = password
+[database_replica.two]
+host = 127.0.0.1:3308
+type = mysql
+name = grafana
+user = grafana
+password = password`