feat(backup): add validated archives and recoverable restore journals

internal/store/backup.go

@@ -0,0 +1,92 @@
+package store
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"net/url"
+	"strings"
+)
+
+// Snapshot 使用 SQLite 生成一致的独立数据库，不复制活动 WAL 文件。
+func (s *Store) Snapshot(ctx context.Context, dest string) error {
+	_, err := s.db.ExecContext(ctx, `VACUUM INTO ?`, dest)
+	return err
+}
+func (s *Store) Preferences() (map[string]json.RawMessage, error) {
+	rows, err := s.db.Query(`SELECT key,value FROM settings WHERE key IN ('app.settings','plugins.enabled') OR key GLOB 'plugin.data.*' ORDER BY key`)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	result := map[string]json.RawMessage{}
+	for rows.Next() {
+		var key, value string
+		if err := rows.Scan(&key, &value); err != nil {
+			return nil, err
+		}
+		if !json.Valid([]byte(value)) {
+			return nil, fmt.Errorf("设置 %s 格式无效", key)
+		}
+		result[key] = json.RawMessage(value)
+	}
+	return result, rows.Err()
+}
+
+// ReplacePreferences 一次提交全部偏好，账户与会话不属于设置包。
+func (s *Store) ReplacePreferences(values map[string]json.RawMessage) error {
+	tx, err := s.db.Begin()
+	if err != nil {
+		return err
+	}
+	defer tx.Rollback()
+	if _, err = tx.Exec(`DELETE FROM settings WHERE key IN ('app.settings','plugins.enabled') OR key GLOB 'plugin.data.*'`); err != nil {
+		return err
+	}
+	for key, value := range values {
+		if (key != "app.settings" && key != "plugins.enabled" && !strings.HasPrefix(key, "plugin.data.")) || !json.Valid(value) {
+			return fmt.Errorf("设置包含无效设置项")
+		}
+		if _, err = tx.Exec(`INSERT INTO settings(key,value) VALUES (?,?)`, key, string(value)); err != nil {
+			return err
+		}
+	}
+	return tx.Commit()
+}
+func (s *Store) ResetPreferences() error {
+	_, err := s.db.Exec(`DELETE FROM settings WHERE key IN ('app.settings','plugins.enabled')`)
+	return err
+}
+func (s *Store) ClearSessions() error { _, err := s.db.Exec(`DELETE FROM sessions`); return err }
+
+// CheckBackup 确认数据库可读取且包含当前版本所需表；不会初始化或修复传入文件。
+func (s *Store) CheckBackup() error {
+	var result string
+	if err := s.db.QueryRow(`PRAGMA quick_check`).Scan(&result); err != nil {
+		return err
+	}
+	if result != "ok" {
+		return errors.New("备份数据库完整性检查失败")
+	}
+	for _, query := range []string{`SELECT key,value FROM settings LIMIT 0`, `SELECT token_hash,created_at,expires_at FROM sessions LIMIT 0`, `SELECT id,name,token_hash,scope,created_at,last_used_at FROM api_tokens LIMIT 0`} {
+		rows, err := s.db.Query(query)
+		if err != nil {
+			return err
+		}
+		if err = rows.Close(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// OpenExisting 只打开已有库；导入校验不得创建表或更改日志模式。
+func OpenExisting(path string) (*Store, error) {
+	db, err := sql.Open("sqlite", (&url.URL{Scheme: "file", Path: path, RawQuery: "mode=rw&_pragma=busy_timeout(5000)"}).String())
+	if err != nil {
+		return nil, err
+	}
+	return &Store{db: db}, nil
+}