SQL

Question

我一直致力于将 Kotlin Multiplatform 项目上的数据库从未加密迁移到加密。这一切都是在 Android 上完成的，但是 iOS 部分被证明是棘手的。最后我让它有点工作了，但是当我 return 数据库驱动程序时，我得到这个错误：

Function doesn't have or inherit @Throws annotation and thus exception isn't propagated from Kotlin to Objective-C/Swift as NSError. It is considered unexpected and unhandled instead. Program will be terminated. Uncaught Kotlin exception: kotlin.Exception: android/database/sqlite/SQLiteDatabaseCorruptException - file is not a database (code 26): , while compiling: PRAGMA journal_mode

它提到 android/database 很奇怪，我不确定为什么。不管怎样，对于迁移，我有日志设置，我可以看到它执行它，如果我调试应用程序并拉取数据库，它看起来确实像数据库现在已经加密并且上面也有旧数据。当它到达这段代码时似乎崩溃了：

NativeSqliteDriver(DatabaseConfiguration(
    name = DatabaseName,
    version = AppDatabase.Schema.version,
    create = { connection -> wrapConnection(connection) { AppDatabase.Schema.create(it) } },
    upgrade = { connection, oldVersion, newVersion ->
        try {
            wrapConnection(connection) {
                NSLog("old version is ${oldVersion} new version is ${newVersion}")
                AppDatabase.Schema.migrate(it, oldVersion, newVersion)
            }
        } catch (exception: Exception) {
            NSLog("exception is ${exception.toString()}")
        }
     }
     //Workaround for DatabaseConnection.setCipherKey causing an exception on iOS 14
     configConnection = { connection, _ ->
         val statement = "PRAGMA key = \"$password\";"
         connection.withStatement(statement) {
             stringForQuery()
         }
     }
))

断点从不在升级中触发 try/catch。迁移逻辑如下所示，在 returning NativeSqlLiteDriver 之前执行。

@ExperimentalUnsignedTypes
override fun migrateToEncryptedDatabase(databasePath: String, temporaryDatabasePath: String, password: String) {
    val fileManager = NSFileManager.defaultManager()
    fileManager.createFileAtPath(temporaryDatabasePath, null, null)

    if (fileManager.fileExistsAtPath(databasePath)) {
        memScoped {
            val unencryptedDb: CPointerVar<sqlite3> = allocPointerTo()
            val encryptedDb: CPointerVar<sqlite3> = allocPointerTo()

            if (sqlite3_open(databasePath, unencryptedDb.ptr) == SQLITE_OK) {
                val exec1 = sqlite3_exec(unencryptedDb.value, "ATTACH DATABASE '$temporaryDatabasePath' AS encrypted KEY '$password';", null, null, null)
                val exec2 = sqlite3_exec(unencryptedDb.value, "SELECT sqlcipher_export('encrypted')", null, null, null)
                val exec3 = sqlite3_exec(unencryptedDb.value, "DETACH DATABASE encrypted;", null, null, null)

                val version = sqlite3_version
                sqlite3_close(unencryptedDb.value)

                if (sqlite3_open(temporaryDatabasePath, encryptedDb.ptr) == SQLITE_OK) {
                    sqlite3_key(encryptedDb.value, password.cstr, password.cstr.size)
                }
                sqlite3_close(unencryptedDb.value)

                val error: ObjCObjectVar<NSError?> = alloc()
                val removeResult = fileManager.removeItemAtPath(databasePath, error.ptr)

                if (removeResult == false) {
                    NSLog("Error removing db file: " + error.value)
                } else {

                }

                val result = fileManager.moveItemAtPath(temporaryDatabasePath, databasePath, error.ptr)

                if (result == false) {
                    NSLog("Error moving db file: " + error.value)
                } else {

                }
            } else {
                NSLog("Failed to open the unencrypted DB with message: " + sqlite3_errmsg(unencryptedDb.value))
                sqlite3_close(unencryptedDb.value)
            }
        }
    }
}

感谢您的帮助

Answer 1

这其实是没有正确更新版本造成的。测试时，我以为我已经正确更新了版本，但它仍然返回 0 而不是 1。我通过这样做解决了它。首先是检索当前数据库版本的方法：

private fun getUserVersion(unencryptedDBPointer: CPointerVar<sqlite3>): Int? {
    memScoped {
        val sqliteStatementPointer: CPointerVar<sqlite3_stmt> = allocPointerTo()
        var databaseVersion: Int? = null

        if (sqlite3_prepare_v2(unencryptedDBPointer.value, "PRAGMA user_version;", USER_VERSION_STATEMENT_MAX_LENGTH, sqliteStatementPointer.ptr, null) == SQLITE_OK) {
            while (sqlite3_step(sqliteStatementPointer.value) == SQLITE_ROW) {
                databaseVersion = sqlite3_column_int(sqliteStatementPointer.value, COLUMN_TO_USE)
            }
        } else {
            Logger.d("Error preparing the database: ${sqlite3_errmsg(unencryptedDBPointer.value)}")
        }

        sqlite3_finalize(sqliteStatementPointer.value)

        return databaseVersion
    }
}

然后，在我的迁移方法中，我有以下代码：

val dbVersion = getUserVersion(unencryptedDbPointer)

if (sqlite3_open(temporaryDatabasePath, encryptedDbPointer.ptr) == SQLITE_OK && dbVersion != null) {
     sqlite3_key(encryptedDbPointer.value, password.cstr, password.cstr.size)
     sqlite3_exec(encryptedDbPointer.value, "PRAGMA user_version=$dbVersion", null, null, null)
}

这在数据库上正确设置了版本并解决了问题。

SQL - SQLiteDatabaseCorruptException - 编译时文件不是数据库：PRAGMA journal_mode

SQL - SQLiteDatabaseCorruptException - file is not a database while compiling: PRAGMA journal_mode

objective-c

sqlite

kotlin

sqlcipher