githaven/models/user/follow.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

81 lines
2.2 KiB
Go

// Copyright 2017 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 user
import (
"code.gitea.io/gitea/models/db"
"code.gitea.io/gitea/modules/timeutil"
)
// Follow represents relations of user and their followers.
type Follow struct {
ID int64 `xorm:"pk autoincr"`
UserID int64 `xorm:"UNIQUE(follow)"`
FollowID int64 `xorm:"UNIQUE(follow)"`
CreatedUnix timeutil.TimeStamp `xorm:"INDEX created"`
}
func init() {
db.RegisterModel(new(Follow))
}
// IsFollowing returns true if user is following followID.
func IsFollowing(userID, followID int64) bool {
has, _ := db.GetEngine(db.DefaultContext).Get(&Follow{UserID: userID, FollowID: followID})
return has
}
// FollowUser marks someone be another's follower.
func FollowUser(userID, followID int64) (err error) {
if userID == followID || IsFollowing(userID, followID) {
return nil
}
ctx, committer, err := db.TxContext(db.DefaultContext)
if err != nil {
return err
}
defer committer.Close()
if err = db.Insert(ctx, &Follow{UserID: userID, FollowID: followID}); err != nil {
return err
}
if _, err = db.Exec(ctx, "UPDATE `user` SET num_followers = num_followers + 1 WHERE id = ?", followID); err != nil {
return err
}
if _, err = db.Exec(ctx, "UPDATE `user` SET num_following = num_following + 1 WHERE id = ?", userID); err != nil {
return err
}
return committer.Commit()
}
// UnfollowUser unmarks someone as another's follower.
func UnfollowUser(userID, followID int64) (err error) {
if userID == followID || !IsFollowing(userID, followID) {
return nil
}
ctx, committer, err := db.TxContext(db.DefaultContext)
if err != nil {
return err
}
defer committer.Close()
if _, err = db.DeleteByBean(ctx, &Follow{UserID: userID, FollowID: followID}); err != nil {
return err
}
if _, err = db.Exec(ctx, "UPDATE `user` SET num_followers = num_followers - 1 WHERE id = ?", followID); err != nil {
return err
}
if _, err = db.Exec(ctx, "UPDATE `user` SET num_following = num_following - 1 WHERE id = ?", userID); err != nil {
return err
}
return committer.Commit()
}