1 files changed, 152 insertions, 0 deletions
diff --git a/models/system/setting.go b/models/system/setting.go
new file mode 100644
index 00000000..4472b4c2
--- /dev/null
+++ b/models/system/setting.go
@@ -0,0 +1,152 @@
+// Copyright 2021 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package system
+
+import (
+	"context"
+	"math"
+	"sync"
+	"time"
+
+	"code.gitea.io/gitea/models/db"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/setting/config"
+	"code.gitea.io/gitea/modules/timeutil"
+
+	"xorm.io/builder"
+)
+
+type Setting struct {
+	ID           int64              `xorm:"pk autoincr"`
+	SettingKey   string             `xorm:"varchar(255) unique"` // key should be lowercase
+	SettingValue string             `xorm:"text"`
+	Version      int                `xorm:"version"`
+	Created      timeutil.TimeStamp `xorm:"created"`
+	Updated      timeutil.TimeStamp `xorm:"updated"`
+}
+
+// TableName sets the table name for the settings struct
+func (s *Setting) TableName() string {
+	return "system_setting"
+}
+
+func init() {
+	db.RegisterModel(new(Setting))
+}
+
+const keyRevision = "revision"
+
+func GetRevision(ctx context.Context) int {
+	revision, exist, err := db.Get[Setting](ctx, builder.Eq{"setting_key": keyRevision})
+	if err != nil {
+		return 0
+	} else if !exist {
+		err = db.Insert(ctx, &Setting{SettingKey: keyRevision, Version: 1})
+		if err != nil {
+			return 0
+		}
+		return 1
+	}
+	if revision.Version <= 0 || revision.Version >= math.MaxInt-1 {
+		_, err = db.Exec(ctx, "UPDATE system_setting SET version=1 WHERE setting_key=?", keyRevision)
+		if err != nil {
+			return 0
+		}
+		return 1
+	}
+	return revision.Version
+}
+
+func GetAllSettings(ctx context.Context) (revision int, res map[string]string, err error) {
+	_ = GetRevision(ctx) // prepare the "revision" key ahead
+	var settings []*Setting
+	if err := db.GetEngine(ctx).
+		Find(&settings); err != nil {
+		return 0, nil, err
+	}
+	res = make(map[string]string)
+	for _, s := range settings {
+		if s.SettingKey == keyRevision {
+			revision = s.Version
+		}
+		res[s.SettingKey] = s.SettingValue
+	}
+	return revision, res, nil
+}
+
+func SetSettings(ctx context.Context, settings map[string]string) error {
+	_ = GetRevision(ctx) // prepare the "revision" key ahead
+	return db.WithTx(ctx, func(ctx context.Context) error {
+		e := db.GetEngine(ctx)
+		_, err := db.Exec(ctx, "UPDATE system_setting SET version=version+1 WHERE setting_key=?", keyRevision)
+		if err != nil {
+			return err
+		}
+		for k, v := range settings {
+			res, err := e.Exec("UPDATE system_setting SET version=version+1, setting_value=? WHERE setting_key=?", v, k)
+			if err != nil {
+				return err
+			}
+			rows, _ := res.RowsAffected()
+			if rows == 0 { // if no existing row, insert a new row
+				if _, err = e.Insert(&Setting{SettingKey: k, SettingValue: v}); err != nil {
+					return err
+				}
+			}
+		}
+		return nil
+	})
+}
+
+type dbConfigCachedGetter struct {
+	mu sync.RWMutex
+
+	cacheTime time.Time
+	revision  int
+	settings  map[string]string
+}
+
+var _ config.DynKeyGetter = (*dbConfigCachedGetter)(nil)
+
+func (d *dbConfigCachedGetter) GetValue(ctx context.Context, key string) (v string, has bool) {
+	d.mu.RLock()
+	defer d.mu.RUnlock()
+	v, has = d.settings[key]
+	return v, has
+}
+
+func (d *dbConfigCachedGetter) GetRevision(ctx context.Context) int {
+	d.mu.RLock()
+	cachedDuration := time.Since(d.cacheTime)
+	cachedRevision := d.revision
+	d.mu.RUnlock()
+
+	if cachedDuration < time.Second {
+		return cachedRevision
+	}
+
+	d.mu.Lock()
+	defer d.mu.Unlock()
+	if GetRevision(ctx) != d.revision {
+		rev, set, err := GetAllSettings(ctx)
+		if err != nil {
+			log.Error("Unable to get all settings: %v", err)
+		} else {
+			d.revision = rev
+			d.settings = set
+		}
+	}
+	d.cacheTime = time.Now()
+	return d.revision
+}
+
+func (d *dbConfigCachedGetter) InvalidateCache() {
+	d.mu.Lock()
+	d.cacheTime = time.Time{}
+	d.mu.Unlock()
+}
+
+func NewDatabaseDynKeyGetter() config.DynKeyGetter {
+	return &dbConfigCachedGetter{}
+}