Skip to content

CLASS

SQLiteWorkspace

public final class SQLiteWorkspace: Workspace

Methods

init(filePath:fileProtectionLevel:synchronous:writeConcurrency:targetQueue:)

public required init(filePath: String, fileProtectionLevel: FileProtectionLevel, synchronous: Synchronous = .normal, writeConcurrency: WriteConcurrency = .concurrent, targetQueue: DispatchQueue? = nil)

Return a SQLite backed Workspace instance.

  • Parameters:
    • filePath: The path to the SQLite file. There will be 3 files named filePath, "(filePath)-wal" and "(filePath)-shm" created.
    • fileProtectionLevel: The expected protection level for the database file.
    • synchronous: The SQLite synchronous mode, read: https://www.sqlite.org/wal.html#performance_considerations
    • writeConcurrency: Either .concurrent or .serial.
    • targetQueue: If nil, we will create a queue based on writeConcurrency settings. If you supply your own queue, please read about WriteConcurrency before proceed.

Parameters

Name Description
filePath The path to the SQLite file. There will be 3 files named filePath, “(filePath)-wal” and “(filePath)-shm” created.
fileProtectionLevel The expected protection level for the database file.
synchronous The SQLite synchronous mode, read: https://www.sqlite.org/wal.html#performance_considerations
writeConcurrency Either .concurrent or .serial.
targetQueue If nil, we will create a queue based on writeConcurrency settings. If you supply your own queue, please read about WriteConcurrency before proceed.

shutdown(completion:)

public func shutdown(completion: (() -> Void)?)

performChanges(_:changesHandler:completionHandler:)

public func performChanges(_ transactionalObjectTypes: [Any.Type], changesHandler: @escaping Workspace.ChangesHandler, completionHandler: Workspace.CompletionHandler? = nil)

Parameters

Name Description
transactionalObjectTypes A list of object types you are going to transact with. If you If you fetch or mutation an object outside of this list, it will fatal.
changesHandler The transaction closure where you will give a transactionContext and safe to do data mutations through submission of change requests.
completionHandler If supplied, will be called once the transaction committed. It will be called with success / failure. You don’t need to handle failure cases specifically (such as retry), but rather to surface and log such error.

fetch(for:)

public func fetch<Element: Atom>(for ofType: Element.Type) -> QueryBuilder<Element>

fetchWithinASnapshot(_:)

public func fetchWithinASnapshot<T>(_ closure: () -> T) -> T

subscribe(fetchedResult:changeHandler:)

public func subscribe<Element: Atom>(fetchedResult: FetchedResult<Element>, changeHandler: @escaping (_: FetchedResult<Element>) -> Void) -> Workspace.Subscription where Element: Equatable

Parameters

Name Description
fetchedResult The original fetchedResult. If it is outdated already, you will get an updated callback soon after.
changeHandler The callback where you will receive an update if anything changed.

subscribe(object:changeHandler:)

public func subscribe<Element: Atom>(object: Element, changeHandler: @escaping (_: SubscribedObject<Element>) -> Void) -> Workspace.Subscription where Element: Equatable

Parameters

Name Description
object The object to be observed. If it is outdated already, you will get an updated callback soon after.
changeHandler The callback where you will receive an update if anything changed.

publisher(for:)

public func publisher<Element: Atom>(for object: Element) -> AtomPublisher<Element> where Element: Equatable

publisher(for:)

public func publisher<Element: Atom>(for fetchedResult: FetchedResult<Element>) -> FetchedResultPublisher<Element> where Element: Equatable

publisher(for:)

public func publisher<Element: Atom>(for: Element.Type) -> QueryPublisherBuilder<Element> where Element: Equatable

ENUM

SQLiteWorkspace.FileProtectionLevel

public enum FileProtectionLevel: Int32

Cases

noProtection

case noProtection = 4

Class D: No protection. If the device is booted, in theory, you can access the content. When it is not booted, the content is protected by the Secure Enclave's hardware key.

completeFileProtection

case completeFileProtection = 1

Class A: The file is accessible if the phone is unlocked and the app is in foreground. You will lose the file access if the app is backgrounded or the phone is locked.

completeFileProtectionUnlessOpen

case completeFileProtectionUnlessOpen = 2

Class B: The file is accessible if the phone is unlocked. You will lose the file access if the phone is locked.

completeFileProtectionUntilFirstUserAuthentication

case completeFileProtectionUntilFirstUserAuthentication = 3

Class C: The file is accessible once user unlocked the phone once. The file cannot be accessed prior to that. For example, if you received a notification before first device unlock, the underlying database cannot be open successfully.

ENUM

SQLiteWorkspace.WriteConcurrency

public enum WriteConcurrency

Cases

concurrent

case concurrent

Enable strict serializable multi-writer / multi-reader mode. Note that SQLite under the hood still writes serially. It only means the transaction closures can be executed concurrently. If you provided a targetQueue, please make sure it is a concurrent queue otherwise it will still execute transaction closure serially. The targetQueue is supplied by you, should be at reasonable priority, at least .default, because it sets the ceiling for any sub-queues targeting that, and we may need to bump the sub-queues depending on where you performChanges.

serial

case serial

Enable single-writer / multi-reader mode. This will execute transaction closures serially. If you supply a targetQueue, please make sure it is serial. It is safe for this serial queue to have lower priority such as .utility, because we can bump the priority based on where you call performChanges.

ENUM

SQLiteWorkspace.Synchronous

public enum Synchronous

The synchronous mode of SQLite. We defaults to .normal. Read more on: https://www.sqlite.org/wal.html#performance_considerations

Cases

normal

case normal

full

case full