BackupKit/com.vocabloot.backupkit/CloudKitStorage

CloudKitStorage

class CloudKitStorage(checkpointPath: String, cacheDirectory: String, containerIdentifier: String? = null, zoneName: String = "backupkit", recordType: String = "BackupEntry", environment: String = "") : CloudStorage(source)

CloudKit transport: one custom zone in the user's private database, one record per file, the bytes as a CKAsset. Unlike the iCloud Drive container there are no placeholder files: a save completes when Apple's server has the record, and a read is a network fetch with a definite outcome.

remoteId is always null and sizes are always known.
list fetches zone changes since the last checkpoint (checkpointPath, one atomic JSON file holding the change token together with the records it stands for) and never downloads assets.
readBytes and downloadFile serve from a local cache under cacheDirectory when the cached copy matches the record's change tag; prefetch fills that cache eight records per request, two requests in flight.
Pass environment as "development" for debug builds and "production" otherwise: Xcode's debug builds talk to the Development container, and the two must never share a checkpoint on one device.

Entitlements: com.apple.developer.icloud-services = [CloudKit] and the container in com.apple.developer.icloud-container-identifiers. The BackupEntry record type and the zone are created automatically in the Development environment; deploy the schema to Production in the CloudKit console before a TestFlight build.

Constructors

CloudKitStorage

constructor(checkpointPath: String, cacheDirectory: String, containerIdentifier: String? = null, zoneName: String = "backupkit", recordType: String = "BackupEntry", environment: String = "")

Properties

provider

open override val provider: CloudProvider

Functions

availability

open suspend override fun availability(): CloudAvailability

Cheap. Never touches the network.

delete

open suspend override fun delete(path: String, remoteId: String?)

No-op when already absent.

downloadFile

open suspend override fun downloadFile(path: String, toLocalPath: String, remoteId: String?)

Downloads into toLocalPath, replacing it. Throws CloudError.NotFound when absent.

exists

open suspend override fun exists(path: String): Boolean

identityKey

open suspend override fun identityKey(): String?

Stable per (device, cloud account) when the platform can tell, so a sync engine can detect an account switch. Null on Drive, where the engine keys identity off the marker file's id.

list

open suspend override fun list(): List<RemoteFile>

Every file, deduplicated by path (newest wins).

prefetch

open suspend override fun prefetch(paths: List<String>)

Starts downloading every not-yet-local file in paths at once, without waiting. iCloud only; Drive has nothing to prefetch. Never throws. Call it before a restore so files download in parallel instead of one at a time.

readBytes

open suspend override fun readBytes(path: String, remoteId: String?): ByteArray?

Whole contents, or null when absent. Forces an iCloud download first.

writeBytes

open suspend override fun writeBytes(path: String, bytes: ByteArray, mimeType: String, existingRemoteId: String?): String?

Create or replace from memory. Returns the remote id on Drive, null on iCloud.

writeFile

open suspend override fun writeFile(path: String, localPath: String, mimeType: String, existingRemoteId: String?): String?

Create or replace from a local file. Returns the remote id on Drive, null on iCloud.