1 files changed, 140 insertions, 0 deletions
diff --git a/models/db/engine_init.go b/models/db/engine_init.go
new file mode 100644
index 0000000000..da85018957
--- /dev/null
+++ b/models/db/engine_init.go
@@ -0,0 +1,140 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package db
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/setting"
+
+	"xorm.io/xorm"
+	"xorm.io/xorm/names"
+)
+
+func init() {
+	gonicNames := []string{"SSL", "UID"}
+	for _, name := range gonicNames {
+		names.LintGonicMapper[name] = true
+	}
+}
+
+// newXORMEngine returns a new XORM engine from the configuration
+func newXORMEngine() (*xorm.Engine, error) {
+	connStr, err := setting.DBConnStr()
+	if err != nil {
+		return nil, err
+	}
+
+	var engine *xorm.Engine
+
+	if setting.Database.Type.IsPostgreSQL() && len(setting.Database.Schema) > 0 {
+		// OK whilst we sort out our schema issues - create a schema aware postgres
+		registerPostgresSchemaDriver()
+		engine, err = xorm.NewEngine("postgresschema", connStr)
+	} else {
+		engine, err = xorm.NewEngine(setting.Database.Type.String(), connStr)
+	}
+
+	if err != nil {
+		return nil, err
+	}
+	if setting.Database.Type == "mysql" {
+		engine.Dialect().SetParams(map[string]string{"rowFormat": "DYNAMIC"})
+	} else if setting.Database.Type == "mssql" {
+		engine.Dialect().SetParams(map[string]string{"DEFAULT_VARCHAR": "nvarchar"})
+	}
+	engine.SetSchema(setting.Database.Schema)
+	return engine, nil
+}
+
+// InitEngine initializes the xorm.Engine and sets it as db.DefaultContext
+func InitEngine(ctx context.Context) error {
+	xe, err := newXORMEngine()
+	if err != nil {
+		if strings.Contains(err.Error(), "SQLite3 support") {
+			return fmt.Errorf(`sqlite3 requires: -tags sqlite,sqlite_unlock_notify%s%w`, "\n", err)
+		}
+		return fmt.Errorf("failed to connect to database: %w", err)
+	}
+
+	xe.SetMapper(names.GonicMapper{})
+	// WARNING: for serv command, MUST remove the output to os.stdout,
+	// so use log file to instead print to stdout.
+	xe.SetLogger(NewXORMLogger(setting.Database.LogSQL))
+	xe.ShowSQL(setting.Database.LogSQL)
+	xe.SetMaxOpenConns(setting.Database.MaxOpenConns)
+	xe.SetMaxIdleConns(setting.Database.MaxIdleConns)
+	xe.SetConnMaxLifetime(setting.Database.ConnMaxLifetime)
+	xe.SetDefaultContext(ctx)
+
+	if setting.Database.SlowQueryThreshold > 0 {
+		xe.AddHook(&SlowQueryHook{
+			Threshold: setting.Database.SlowQueryThreshold,
+			Logger:    log.GetLogger("xorm"),
+		})
+	}
+
+	SetDefaultEngine(ctx, xe)
+	return nil
+}
+
+// SetDefaultEngine sets the default engine for db
+func SetDefaultEngine(ctx context.Context, eng *xorm.Engine) {
+	xormEngine = eng
+	DefaultContext = &Context{Context: ctx, engine: xormEngine}
+}
+
+// UnsetDefaultEngine closes and unsets the default engine
+// We hope the SetDefaultEngine and UnsetDefaultEngine can be paired, but it's impossible now,
+// there are many calls to InitEngine -> SetDefaultEngine directly to overwrite the `xormEngine` and DefaultContext without close
+// Global database engine related functions are all racy and there is no graceful close right now.
+func UnsetDefaultEngine() {
+	if xormEngine != nil {
+		_ = xormEngine.Close()
+		xormEngine = nil
+	}
+	DefaultContext = nil
+}
+
+// InitEngineWithMigration initializes a new xorm.Engine and sets it as the db.DefaultContext
+// This function must never call .Sync() if the provided migration function fails.
+// When called from the "doctor" command, the migration function is a version check
+// that prevents the doctor from fixing anything in the database if the migration level
+// is different from the expected value.
+func InitEngineWithMigration(ctx context.Context, migrateFunc func(*xorm.Engine) error) (err error) {
+	if err = InitEngine(ctx); err != nil {
+		return err
+	}
+
+	if err = xormEngine.Ping(); err != nil {
+		return err
+	}
+
+	preprocessDatabaseCollation(xormEngine)
+
+	// We have to run migrateFunc here in case the user is re-running installation on a previously created DB.
+	// If we do not then table schemas will be changed and there will be conflicts when the migrations run properly.
+	//
+	// Installation should only be being re-run if users want to recover an old database.
+	// However, we should think carefully about should we support re-install on an installed instance,
+	// as there may be other problems due to secret reinitialization.
+	if err = migrateFunc(xormEngine); err != nil {
+		return fmt.Errorf("migrate: %w", err)
+	}
+
+	if err = SyncAllTables(); err != nil {
+		return fmt.Errorf("sync database struct error: %w", err)
+	}
+
+	for _, initFunc := range registeredInitFuncs {
+		if err := initFunc(); err != nil {
+			return fmt.Errorf("initFunc failed: %w", err)
+		}
+	}
+
+	return nil
+}