Files
CoreStore/Sources/BaseDataTransaction.swift
2018-10-10 16:48:04 +03:00

491 lines
20 KiB
Swift

//
// BaseDataTransaction.swift
// CoreStore
//
// Copyright © 2018 John Rommel Estropia
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//
import Foundation
import CoreData
// MARK: - BaseDataTransaction
/**
The `BaseDataTransaction` is an abstract interface for `NSManagedObject` creates, updates, and deletes. All `BaseDataTransaction` subclasses manage a private `NSManagedObjectContext` which are direct children of the `NSPersistentStoreCoordinator`'s root `NSManagedObjectContext`. This means that all updates are saved first to the persistent store, and then propagated up to the read-only `NSManagedObjectContext`.
*/
public /*abstract*/ class BaseDataTransaction {
// MARK: Object management
/**
Indicates if the transaction has pending changes
*/
public var hasChanges: Bool {
return self.context.hasChanges
}
/**
Creates a new `NSManagedObject` or `CoreStoreObject` with the specified entity type.
- parameter into: the `Into` clause indicating the destination `NSManagedObject` or `CoreStoreObject` entity type and the destination configuration
- returns: a new `NSManagedObject` or `CoreStoreObject` instance of the specified entity type.
*/
public func create<D>(_ into: Into<D>) -> D {
let entityClass = into.entityClass
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to create an entity of type \(cs_typeName(entityClass)) outside its designated queue."
)
let context = self.context
let dataStack = context.parentStack!
let entityIdentifier = EntityIdentifier(entityClass)
if into.inferStoreIfPossible {
switch dataStack.persistentStore(
for: entityIdentifier,
configuration: nil,
inferStoreIfPossible: true
) {
case (let persistentStore?, _):
return entityClass.cs_forceCreate(
entityDescription: dataStack.entityDescription(for: entityIdentifier)!,
into: context,
assignTo: persistentStore
)
case (nil, true):
CoreStore.abort("Attempted to create an entity of type \(cs_typeName(entityClass)) with ambiguous destination persistent store, but the configuration name was not specified.")
default:
CoreStore.abort("Attempted to create an entity of type \(cs_typeName(entityClass)), but a destination persistent store containing the entity type could not be found.")
}
}
else {
switch dataStack.persistentStore(
for: entityIdentifier,
configuration: into.configuration
?? DataStack.defaultConfigurationName,
inferStoreIfPossible: false
) {
case (let persistentStore?, _):
return entityClass.cs_forceCreate(
entityDescription: dataStack.entityDescription(for: entityIdentifier)!,
into: context,
assignTo: persistentStore
)
case (nil, true):
CoreStore.abort("Attempted to create an entity of type \(cs_typeName(entityClass)) with ambiguous destination persistent store, but the configuration name was not specified.")
default:
if let configuration = into.configuration {
CoreStore.abort("Attempted to create an entity of type \(cs_typeName(entityClass)) into the configuration \"\(configuration)\", which it doesn't belong to.")
}
else {
CoreStore.abort("Attempted to create an entity of type \(cs_typeName(entityClass)) into the default configuration, which it doesn't belong to.")
}
}
}
}
/**
Returns an editable proxy of a specified `NSManagedObject` or `CoreStoreObject`.
- parameter object: the `NSManagedObject` or `CoreStoreObject` type to be edited
- returns: an editable proxy for the specified `NSManagedObject` or `CoreStoreObject`.
*/
public func edit<D: DynamicObject>(_ object: D?) -> D? {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to update an entity of type \(cs_typeName(object)) outside its designated queue."
)
guard let object = object else {
return nil
}
return self.context.fetchExisting(object)
}
/**
Returns an editable proxy of the object with the specified `NSManagedObjectID`.
- parameter into: an `Into` clause specifying the entity type
- parameter objectID: the `NSManagedObjectID` for the object to be edited
- returns: an editable proxy for the specified `NSManagedObject` or `CoreStoreObject`.
*/
public func edit<D>(_ into: Into<D>, _ objectID: NSManagedObjectID) -> D? {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to update an entity of type \(cs_typeName(into.entityClass)) outside its designated queue."
)
CoreStore.assert(
into.inferStoreIfPossible
|| (into.configuration ?? DataStack.defaultConfigurationName) == objectID.persistentStore?.configurationName,
"Attempted to update an entity of type \(cs_typeName(into.entityClass)) but the specified persistent store do not match the `NSManagedObjectID`."
)
return self.fetchExisting(objectID)
}
/**
Deletes a specified `NSManagedObject` or `CoreStoreObject`.
- parameter object: the `NSManagedObject` or `CoreStoreObject` to be deleted
*/
public func delete<D: DynamicObject>(_ object: D?) {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to delete an entity outside its designated queue."
)
let context = self.context
object
.flatMap(context.fetchExisting)
.flatMap({ context.delete($0.cs_toRaw()) })
}
/**
Deletes the specified `NSManagedObject`s or `CoreStoreObject`s.
- parameter object1: the `NSManagedObject` or `CoreStoreObject` to be deleted
- parameter object2: another `NSManagedObject` or `CoreStoreObject` to be deleted
- parameter objects: other `NSManagedObject`s or `CoreStoreObject`s to be deleted
*/
public func delete<D: DynamicObject>(_ object1: D?, _ object2: D?, _ objects: D?...) {
self.delete(([object1, object2] + objects).compactMap { $0 })
}
/**
Deletes the specified `NSManagedObject`s or `CoreStoreObject`s.
- parameter objects: the `NSManagedObject`s or `CoreStoreObject`s to be deleted
*/
public func delete<S: Sequence>(_ objects: S) where S.Iterator.Element: DynamicObject {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to delete entities outside their designated queue."
)
let context = self.context
objects.forEach { context.fetchExisting($0).flatMap({ context.delete($0.cs_toRaw()) }) }
}
/**
Refreshes all registered objects `NSManagedObject`s in the transaction.
*/
public func refreshAndMergeAllObjects() {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to refresh entities outside their designated queue."
)
self.context.refreshAndMergeAllObjects()
}
// MARK: Inspecting Pending Objects
/**
Returns all pending `DynamicObject`s of the specified type that were inserted to the transaction. This method should not be called after the `commit()` method was called.
- parameter entity: the `DynamicObject` subclass to filter
- returns: a `Set` of pending `DynamicObject`s of the specified type that were inserted to the transaction.
*/
public func insertedObjects<D: DynamicObject>(_ entity: D.Type) -> Set<D> {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to access inserted objects from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access inserted objects from an already committed \(cs_typeName(self))."
)
return Set(self.context.insertedObjects.compactMap({ entity.cs_matches(object: $0) ? entity.cs_fromRaw(object: $0) : nil }))
}
/**
Returns all pending `NSManagedObjectID`s that were inserted to the transaction. This method should not be called after the `commit()` method was called.
- returns: a `Set` of pending `NSManagedObjectID`s that were inserted to the transaction.
*/
public func insertedObjectIDs() -> Set<NSManagedObjectID> {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to access inserted object IDs from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access inserted objects IDs from an already committed \(cs_typeName(self))."
)
return Set(self.context.insertedObjects.map { $0.objectID })
}
/**
Returns all pending `NSManagedObjectID`s of the specified type that were inserted to the transaction. This method should not be called after the `commit()` method was called.
- parameter entity: the `DynamicObject` subclass to filter
- returns: a `Set` of pending `NSManagedObjectID`s of the specified type that were inserted to the transaction.
*/
public func insertedObjectIDs<D: DynamicObject>(_ entity: D.Type) -> Set<NSManagedObjectID> {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to access inserted object IDs from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access inserted objects IDs from an already committed \(cs_typeName(self))."
)
return Set(self.context.insertedObjects.compactMap({ entity.cs_matches(object: $0) ? $0.objectID : nil }))
}
/**
Returns all pending `DynamicObject`s of the specified type that were updated in the transaction. This method should not be called after the `commit()` method was called.
- parameter entity: the `DynamicObject` subclass to filter
- returns: a `Set` of pending `DynamicObject`s of the specified type that were updated in the transaction.
*/
public func updatedObjects<D: DynamicObject>(_ entity: D.Type) -> Set<D> {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to access updated objects from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access updated objects from an already committed \(cs_typeName(self))."
)
return Set(self.context.updatedObjects.compactMap({ entity.cs_matches(object: $0) ? entity.cs_fromRaw(object: $0) : nil }))
}
/**
Returns all pending `NSManagedObjectID`s that were updated in the transaction. This method should not be called after the `commit()` method was called.
- returns: a `Set` of pending `NSManagedObjectID`s that were updated in the transaction.
*/
public func updatedObjectIDs() -> Set<NSManagedObjectID> {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to access updated object IDs from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access updated object IDs from an already committed \(cs_typeName(self))."
)
return Set(self.context.updatedObjects.map { $0.objectID })
}
/**
Returns all pending `NSManagedObjectID`s of the specified type that were updated in the transaction. This method should not be called after the `commit()` method was called.
- parameter entity: the `DynamicObject` subclass to filter
- returns: a `Set` of pending `NSManagedObjectID`s of the specified type that were updated in the transaction.
*/
public func updatedObjectIDs<D: DynamicObject>(_ entity: D.Type) -> Set<NSManagedObjectID> {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to access updated object IDs from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access updated object IDs from an already committed \(cs_typeName(self))."
)
return Set(self.context.updatedObjects.compactMap({ entity.cs_matches(object: $0) ? $0.objectID : nil }))
}
/**
Returns all pending `DynamicObject`s of the specified type that were deleted from the transaction. This method should not be called after the `commit()` method was called.
- parameter entity: the `DynamicObject` subclass to filter
- returns: a `Set` of pending `DynamicObject`s of the specified type that were deleted from the transaction.
*/
public func deletedObjects<D: DynamicObject>(_ entity: D.Type) -> Set<D> {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to access deleted objects from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access deleted objects from an already committed \(cs_typeName(self))."
)
return Set(self.context.deletedObjects.compactMap({ entity.cs_matches(object: $0) ? entity.cs_fromRaw(object: $0) : nil }))
}
/**
Returns all pending `NSManagedObjectID`s of the specified type that were deleted from the transaction. This method should not be called after the `commit()` method was called.
- parameter entity: the `DynamicObject` subclass to filter
- returns: a `Set` of pending `NSManagedObjectID`s of the specified type that were deleted from the transaction.
*/
public func deletedObjectIDs() -> Set<NSManagedObjectID> {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to access deleted object IDs from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access deleted object IDs from an already committed \(cs_typeName(self))."
)
return Set(self.context.deletedObjects.map { $0.objectID })
}
/**
Returns all pending `NSManagedObjectID`s of the specified type that were deleted from the transaction. This method should not be called after the `commit()` method was called.
- parameter entity: the `DynamicObject` subclass to filter
- returns: a `Set` of pending `NSManagedObjectID`s of the specified type that were deleted from the transaction.
*/
public func deletedObjectIDs<D: DynamicObject>(_ entity: D.Type) -> Set<NSManagedObjectID> {
CoreStore.assert(
self.isRunningInAllowedQueue(),
"Attempted to access deleted object IDs from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access deleted object IDs from an already committed \(cs_typeName(self))."
)
return Set(self.context.deletedObjects.compactMap({ entity.cs_matches(object: $0) ? $0.objectID : nil }))
}
// MARK: 3rd Party Utilities
/**
Allow external libraries to store custom data in the transaction. App code should rarely have a need for this.
```
enum Static {
static var myDataKey: Void?
}
transaction.userInfo[&Static.myDataKey] = myObject
```
- Important: Do not use this method to store thread-sensitive data.
*/
public let userInfo = UserInfo()
// MARK: Internal
internal let context: NSManagedObjectContext
internal let transactionQueue: DispatchQueue
internal let childTransactionQueue = DispatchQueue.serial("com.corestore.datastack.childTransactionQueue")
internal let supportsUndo: Bool
internal let bypassesQueueing: Bool
internal var isCommitted = false
internal var result: (hasChanges: Bool, error: CoreStoreError?)?
internal init(mainContext: NSManagedObjectContext, queue: DispatchQueue, supportsUndo: Bool, bypassesQueueing: Bool) {
let context = mainContext.temporaryContextInTransactionWithConcurrencyType(
queue == .main
? .mainQueueConcurrencyType
: .privateQueueConcurrencyType
)
self.transactionQueue = queue
self.context = context
self.supportsUndo = supportsUndo
self.bypassesQueueing = bypassesQueueing
context.parentTransaction = self
context.isTransactionContext = true
if !supportsUndo {
context.undoManager = nil
}
else if context.undoManager == nil {
context.undoManager = UndoManager()
}
}
internal func isRunningInAllowedQueue() -> Bool {
return self.bypassesQueueing || self.transactionQueue.cs_isCurrentExecutionContext()
}
deinit {
self.context.reset()
}
// MARK: Deprecated
@available(*, deprecated, message: "Use insertedObjects(_:) and pass the specific entity type")
public func insertedObjects() -> Set<NSManagedObject> {
CoreStore.assert(
self.transactionQueue.cs_isCurrentExecutionContext(),
"Attempted to access inserted objects from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access inserted objects from an already committed \(cs_typeName(self))."
)
return self.context.insertedObjects
}
@available(*, deprecated, message: "Use updatedObjects(_:) and pass the specific entity type")
public func updatedObjects() -> Set<NSManagedObject> {
CoreStore.assert(
self.transactionQueue.cs_isCurrentExecutionContext(),
"Attempted to access updated objects from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access updated objects from an already committed \(cs_typeName(self))."
)
return self.context.updatedObjects
}
@available(*, deprecated, message: "Use deletedObjects(_:) and pass the specific entity type")
public func deletedObjects() -> Set<NSManagedObject> {
CoreStore.assert(
self.transactionQueue.cs_isCurrentExecutionContext(),
"Attempted to access deleted objects from a \(cs_typeName(self)) outside its designated queue."
)
CoreStore.assert(
!self.isCommitted,
"Attempted to access deleted objects from an already committed \(cs_typeName(self))."
)
return self.context.deletedObjects
}
}