Renaming project because of cocoapods name clash with HardcoreData :(

CoreStore/Saving and Processing/BaseDataTransaction.swift

@@ -0,0 +1,237 @@
+//
+//  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
+    
+    /**
+    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 fetch<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)
+    }
+    
+    /**
+    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 of type \(typeName(object)) outside its designated queue.")
+        
+        object?.inContext(self.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
+    }
+}