Files
CoreStore/CoreStore/Saving and Processing/BaseDataTransaction.swift
John Rommel Estropia e462ae5a19 fixed demo app
2015-06-04 00:40:19 +09:00

286 lines
11 KiB
Swift

//
// BaseDataTransaction.swift
// CoreStore
//
// Copyright (c) 2014 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
import GCDKit
// MARK: - Into
/**
A `Into` clause contains the destination entity and destination persistent store for a `create(...)` method. A common usage is to just indicate the entity:
let person = transaction.create(Into(MyPersonEntity))
For cases where multiple `NSPersistentStore`'s contain the same entity, the destination configuration's name needs to be specified as well:
let person = transaction.create(Into<MyPersonEntity>("Configuration1"))
This helps the `NSManagedObjectContext` to determine which
*/
public struct Into<T: NSManagedObject> {
// MARK: Public
internal static var defaultConfigurationName: String {
return "PF_DEFAULT_CONFIGURATION_NAME"
}
/**
Initializes an `Into` clause.
Sample Usage:
let person = transaction.create(Into<MyPersonEntity>())
*/
public init(){
self.configuration = nil
self.inferStoreIfPossible = true
}
/**
Initializes an `Into` clause with the specified entity type.
Sample Usage:
let person = transaction.create(Into(MyPersonEntity))
:param: entity the `NSManagedObject` type to be created
*/
public init(_ entity: T.Type) {
self.configuration = nil
self.inferStoreIfPossible = true
}
/**
Initializes an `Into` clause with the specified configuration.
Sample Usage:
let person = transaction.create(Into<MyPersonEntity>("Configuration1"))
:param: configuration the `NSPersistentStore` configuration name to associate the object to. This parameter is required if multiple configurations contain the created `NSManagedObject`'s entity type. Set to `nil` to use the default configuration.
*/
public init(_ configuration: String?) {
self.configuration = configuration
self.inferStoreIfPossible = false
}
/**
Initializes an `Into` clause with the specified entity type and configuration.
Sample Usage:
let person = transaction.create(Into(MyPersonEntity.self, "Configuration1"))
:param: entity the `NSManagedObject` type to be created
:param: configuration the `NSPersistentStore` configuration name to associate the object to. This parameter is required if multiple configurations contain the created `NSManagedObject`'s entity type. Set to `nil` to use the default configuration.
*/
public init(_ entity: T.Type, _ configuration: String?) {
self.configuration = configuration
self.inferStoreIfPossible = false
}
// MARK: Internal
internal let configuration: String?
internal let inferStoreIfPossible: Bool
}
// 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` with the specified entity type.
:param: into the `Into` clause indicating the destination `NSManagedObject` entity type and the destination configuration
:returns: a new `NSManagedObject` instance of the specified entity type.
*/
public func create<T: NSManagedObject>(into: Into<T>) -> T {
CoreStore.assert(self.transactionQueue.isCurrentExecutionContext(), "Attempted to create an entity of type <\(T.self)> outside its designated queue.")
let context = self.context
let object = T.createInContext(context)
if into.inferStoreIfPossible {
switch context.parentStack!.persistentStoreForEntityClass(T.self, configuration: nil, inferStoreIfPossible: true) {
case (.Some(let persistentStore), _):
context.assignObject(object, toPersistentStore: persistentStore)
case (.None, true):
CoreStore.assert(false, "Attempted to create an entity of type \(typeName(object)) with ambiguous destination persistent store, but the configuration name was not specified.")
default:
CoreStore.assert(false, "Attempted to create an entity of type \(typeName(object)), but a destination persistent store containing the entity type could not be found.")
}
}
else {
switch context.parentStack!.persistentStoreForEntityClass(T.self, configuration: into.configuration, inferStoreIfPossible: false) {
case (.Some(let persistentStore), _):
context.assignObject(object, toPersistentStore: persistentStore)
default:
if let configuration = into.configuration {
CoreStore.assert(false, "Attempted to create an entity of type \(typeName(object)) into the configuration \"\(configuration)\", which it doesn't belong to.")
}
else {
CoreStore.assert(false, "Attempted to create an entity of type \(typeName(object)) into the default configuration, which it doesn't belong to.")
}
}
}
return object
}
/**
Returns an editable proxy of a specified `NSManagedObject`.
:param: object the `NSManagedObject` type to be edited
:returns: an editable proxy for the specified `NSManagedObject`.
*/
public func edit<T: NSManagedObject>(object: T?) -> T? {
CoreStore.assert(self.transactionQueue.isCurrentExecutionContext(), "Attempted to update an entity of type \(typeName(object)) outside its designated queue.")
return object?.inContext(self.context)
}
/**
Returns an editable proxy of the object with the specified `NSManagedObjectID`.
:param: into an `Into` clause specifying the entity type
:param: objectID the `NSManagedObjectID` for the object to be edited
:returns: an editable proxy for the specified `NSManagedObject`.
*/
public func edit<T: NSManagedObject>(into: Into<T>, _ objectID: NSManagedObjectID) -> T? {
CoreStore.assert(self.transactionQueue.isCurrentExecutionContext(), "Attempted to update an entity of type <\(T.self)> outside its designated queue.")
CoreStore.assert(into.inferStoreIfPossible || (into.configuration ?? Into.defaultConfigurationName) == objectID.persistentStore?.configurationName, "Attempted to update an entity of type <\(T.self)> but the specified persistent store do not match the `NSManagedObjectID`.")
return T.inContext(self.context, withObjectID: objectID)
}
/**
Deletes a specified `NSManagedObject`.
:param: object the `NSManagedObject` type to be deleted
*/
public func delete(object: NSManagedObject?) {
CoreStore.assert(self.transactionQueue.isCurrentExecutionContext(), "Attempted to delete an entity outside its designated queue.")
object?.inContext(self.context)?.deleteFromContext()
}
/**
Deletes the specified `NSManagedObject`'s.
:param: object1 the `NSManagedObject` type to be deleted
:param: object2 another `NSManagedObject` type to be deleted
:param: objects other `NSManagedObject`s type to be deleted
*/
public func delete(object1: NSManagedObject?, _ object2: NSManagedObject?, _ objects: NSManagedObject?...) {
self.delete([object1, object2] + objects)
}
/**
Deletes the specified `NSManagedObject`'s.
:param: objects the `NSManagedObject`'s type to be deleted
*/
public func delete(objects: [NSManagedObject?]) {
CoreStore.assert(self.transactionQueue.isCurrentExecutionContext(), "Attempted to delete entities outside their designated queue.")
let context = self.context
for object in objects {
object?.inContext(context)?.deleteFromContext()
}
}
// MARK: Saving changes
/**
Rolls back the transaction by resetting the `NSManagedObjectContext`. After calling this method, all `NSManagedObjects` fetched within the transaction will become invalid.
*/
public func rollback() {
CoreStore.assert(self.transactionQueue.isCurrentExecutionContext(), "Attempted to rollback a \(typeName(self)) outside its designated queue.")
self.context.reset()
}
// MARK: Internal
internal let context: NSManagedObjectContext
internal let transactionQueue: GCDQueue
internal let childTransactionQueue: GCDQueue = .createSerial("com.corestore.datastack.childtransactionqueue")
internal var isCommitted = false
internal var result: SaveResult?
internal init(mainContext: NSManagedObjectContext, queue: GCDQueue) {
self.transactionQueue = queue
let context = mainContext.temporaryContextInTransactionWithConcurrencyType(
queue == .Main
? .MainQueueConcurrencyType
: .PrivateQueueConcurrencyType
)
self.context = context
context.parentTransaction = self
}
}