forgejo/models/system/appstate.go
Lunny Xiao 34283a74e8
Allow detect whether it's in a database transaction for a context.Context (#21756)
Fix #19513

This PR introduce a new db method `InTransaction(context.Context)`,
and also builtin check on `db.TxContext` and `db.WithTx`.
There is also a new method `db.AutoTx` has been introduced but could be used by other PRs.

`WithTx` will always open a new transaction, if a transaction exist in context, return an error.
`AutoTx` will try to open a new transaction if no transaction exist in context.
That means it will always enter a transaction if there is no error.

Co-authored-by: delvh <dev.lh@web.de>
Co-authored-by: 6543 <6543@obermui.de>
2022-11-12 21:18:50 +01:00

57 lines
1.5 KiB
Go

// Copyright 2021 The Gitea Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.
package system
import (
"context"
"code.gitea.io/gitea/models/db"
)
// AppState represents a state record in database
// if one day we would make Gitea run as a cluster,
// we can introduce a new field `Scope` here to store different states for different nodes
type AppState struct {
ID string `xorm:"pk varchar(200)"`
Revision int64
Content string `xorm:"LONGTEXT"`
}
func init() {
db.RegisterModel(new(AppState))
}
// SaveAppStateContent saves the app state item to database
func SaveAppStateContent(key, content string) error {
return db.WithTx(db.DefaultContext, func(ctx context.Context) error {
eng := db.GetEngine(ctx)
// try to update existing row
res, err := eng.Exec("UPDATE app_state SET revision=revision+1, content=? WHERE id=?", content, key)
if err != nil {
return err
}
rows, _ := res.RowsAffected()
if rows != 0 {
// the existing row is updated, so we can return
return nil
}
// if no existing row, insert a new row
_, err = eng.Insert(&AppState{ID: key, Content: content})
return err
})
}
// GetAppStateContent gets an app state from database
func GetAppStateContent(key string) (content string, err error) {
e := db.GetEngine(db.DefaultContext)
appState := &AppState{ID: key}
has, err := e.Get(appState)
if err != nil {
return "", err
} else if !has {
return "", nil
}
return appState.Content, nil
}