additional safety for transactions by splitting between sync and async subclasses

HardcoreData/AsynchronousDataTransaction.swift

@@ -0,0 +1,125 @@
+//
+//  AsynchronousDataTransaction.swift
+//  HardcoreData
+//
+//  Copyright (c) 2015 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 GCDKit
+
+
+/**
+The AsynchronousDataTransaction provides an interface for NSManagedObject creates, updates, and deletes. A transaction object should typically be only used from within a transaction block initiated from DataStack.performTransaction(_:), or from HardcoreData.performTransaction(_:).
+*/
+public class AsynchronousDataTransaction: DataTransaction {
+    
+    // MARK: Public
+    
+    /**
+    Saves the transaction changes asynchronously. Note that this method should not be used after either the commit(_:) or commitAndWait() method was already called once.
+    
+    :param: completion the block executed after the save completes. Success or failure is reported by the SaveResult argument of the block.
+    */
+    public func commit(completion: (result: SaveResult) -> Void) {
+        
+        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to commit a \(self.dynamicType) outside a transaction queue.")
+        HardcoreData.assert(!self.isCommitted, "Attempted to commit a \(self.dynamicType) more than once.")
+        
+        self.isCommitted = true
+        let semaphore = GCDSemaphore(0)
+        self.context.saveAsynchronouslyWithCompletion { (result) -> Void in
+            
+            self.result = result
+            completion(result: result)
+            semaphore.signal()
+        }
+        semaphore.wait()
+    }
+    
+    /**
+    Saves the transaction changes and waits for completion synchronously. Note that this method should not be used after either the commit(_:) or commitAndWait() method was already called once.
+    
+    :returns: a SaveResult value indicating success or failure.
+    */
+    public func commitAndWait() {
+        
+        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to commit a \(self.dynamicType) outside a transaction queue.")
+        HardcoreData.assert(!self.isCommitted, "Attempted to commit a \(self.dynamicType) more than once.")
+        
+        self.isCommitted = true
+        self.result = self.context.saveSynchronously()
+    }
+    
+    /**
+    Begins a child transaction synchronously where NSManagedObject creates, updates, and deletes can be made.
+    
+    :param: closure the block where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent NSManagedObjectContext.
+    :returns: a SaveResult value indicating success or failure, or nil if the transaction was not comitted synchronously
+    */
+    public func performTransactionAndWait(closure: (transaction: SynchronousDataTransaction) -> Void) -> SaveResult? {
+        
+        return SynchronousDataTransaction(
+            mainContext: self.context,
+            queue: self.childTransactionQueue,
+            closure: closure).performAndWait()
+    }
+    
+    
+    // MARK: Internal
+    
+    internal init(mainContext: NSManagedObjectContext, queue: GCDQueue, closure: (transaction: AsynchronousDataTransaction) -> Void) {
+        
+        self.closure = closure
+        
+        super.init(mainContext: mainContext, queue: queue)
+    }
+    
+    internal func perform() {
+        
+        self.transactionQueue.async {
+            
+            self.closure(transaction: self)
+            if !self.isCommitted {
+                
+                HardcoreData.log(.Warning, message: "The closure for the \(self.dynamicType) completed without being committed. All changes made within the transaction were discarded.")
+            }
+        }
+    }
+    
+    internal func performAndWait() -> SaveResult? {
+        
+        self.transactionQueue.sync {
+            
+            self.closure(transaction: self)
+            if !self.isCommitted {
+                
+                HardcoreData.log(.Warning, message: "The closure for the \(self.dynamicType) completed without being committed. All changes made within the transaction were discarded.")
+            }
+        }
+        return self.result
+    }
+    
+    
+    // MARK: Private
+    
+    private let closure: (transaction: AsynchronousDataTransaction) -> Void
+}

HardcoreData/DataStack+Transaction.swift

@@ -38,11 +38,11 @@ public extension DataStack {
     
     :param: closure the block where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent NSManagedObjectContext.
     */
-    public func performTransaction(closure: (transaction: DataTransaction) -> Void) {
+    public func performTransaction(closure: (transaction: AsynchronousDataTransaction) -> Void) {
         
-        DataTransaction(
+        AsynchronousDataTransaction(
             mainContext: self.mainContext,
-            queue: self.transactionQueue,
+            queue: self.childTransactionQueue,
             closure: closure).perform()
     }
     
@@ -52,11 +52,11 @@ public extension DataStack {
     :param: closure the block where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent NSManagedObjectContext.
     :returns: a SaveResult value indicating success or failure, or nil if the transaction was not comitted synchronously
     */
-    public func performTransactionAndWait(closure: (transaction: DataTransaction) -> Void) -> SaveResult? {
+    public func performTransactionAndWait(closure: (transaction: SynchronousDataTransaction) -> Void) -> SaveResult? {
         
-        return DataTransaction(
+        return SynchronousDataTransaction(
             mainContext: self.mainContext,
-            queue: self.transactionQueue,
+            queue: self.childTransactionQueue,
             closure: closure).performAndWait()
     }
 }

HardcoreData/DataStack.swift

@@ -66,7 +66,7 @@ public class DataStack {
     /**
     Initializes a DataStack from an NSManagedObjectModel.
     
-    :param: modelName the name of the "momd" (or xcdatamodeld) file.
+    :param: managedObjectModel the NSManagedObjectModel of the (.xcdatamodeld) model file.
     */
     public required init(managedObjectModel: NSManagedObjectModel) {
         
@@ -82,8 +82,6 @@ public class DataStack {
             return mapping
         }
         
-        println(self.entityNameMapping)
-        
         self.rootSavingContext.parentStack = self
     }
     
@@ -268,7 +266,7 @@ public class DataStack {
     // MARK: Internal
     
     internal let mainContext: NSManagedObjectContext
-    internal let transactionQueue: GCDQueue = .createSerial("com.hardcoredata.datastack.transactionqueue")
+    internal let childTransactionQueue: GCDQueue = .createSerial("com.hardcoredata.datastack.childtransactionqueue")
     
     internal func entityNameForEntityClass(entityClass: NSManagedObject.Type) -> String? {
         

HardcoreData/DataTransaction.swift

@@ -33,10 +33,7 @@ import GCDKit
 /**
 The DataTransaction provides an interface for NSManagedObject creates, updates, and deletes. A transaction object should typically be only used from within a transaction block initiated from DataStack.performTransaction(_:), or from HardcoreData.performTransaction(_:).
 */
-public final class DataTransaction {
-    
-    // MARK: - Public
-    
+public /*abstract*/ class DataTransaction {
     
     // MARK: Object management
     
@@ -48,8 +45,9 @@ public final class DataTransaction {
     */
     public func create<T: NSManagedObject>(entity: T.Type) -> T {
         
-        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to create an NSManagedObject outside a transaction queue.")
-        HardcoreData.assert(!self.isCommitted, "Attempted to create an NSManagedObject from an already committed DataTransaction.")
+        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to create an entity of type \(entity) outside a transaction queue.")
+        HardcoreData.assert(!self.isCommitted, "Attempted to create an NSManagedObject from an already committed \(self.dynamicType).")
+        
         return T.createInContext(self.context)
     }
     
@@ -61,8 +59,9 @@ public final class DataTransaction {
     */
     public func fetch<T: NSManagedObject>(object: T) -> T? {
         
-        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to update an NSManagedObject outside a transaction queue.")
-        HardcoreData.assert(!self.isCommitted, "Attempted to update an NSManagedObject from an already committed DataTransaction.")
+        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to update an entity of type \(object.dynamicType) outside a transaction queue.")
+        HardcoreData.assert(!self.isCommitted, "Attempted to update an entity of type \(object.dynamicType) from an already committed \(self.dynamicType).")
+        
         return object.inContext(self.context)
     }
     
@@ -73,8 +72,9 @@ public final class DataTransaction {
     */
     public func delete(object: NSManagedObject) {
         
-        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to delete an NSManagedObject outside a transaction queue.")
-        HardcoreData.assert(!self.isCommitted, "Attempted to delete an NSManagedObject from an already committed DataTransaction.")
+        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to delete an entity of type \(object.dynamicType) outside a transaction queue.")
+        HardcoreData.assert(!self.isCommitted, "Attempted to delete an entity of type \(object.dynamicType) from an already committed \(self.dynamicType).")
+        
         object.deleteFromContext()
     }
     
@@ -85,69 +85,25 @@ public final class DataTransaction {
     */
     public func rollback() {
         
-        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to rollback a DataTransaction outside a transaction queue.")
-        HardcoreData.assert(!self.isCommitted, "Attempted to rollback an already committed DataTransaction.")
+        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to rollback a \(self.dynamicType) outside a transaction queue.")
+        HardcoreData.assert(!self.isCommitted, "Attempted to rollback an already committed \(self.dynamicType).")
+        
         self.context.reset()
     }
     
-    /**
-    Saves the transaction changes asynchronously. Note that this method should not be used after either the commit(_:) or commitAndWait() method was already called once.
     
-    :param: completion the block executed after the save completes. Success or failure is reported by the SaveResult argument of the block.
-    */
-    public func commit(completion: (result: SaveResult) -> Void) {
-        
-        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to commit a DataTransaction outside a transaction queue.")
-        HardcoreData.assert(!self.isCommitted, "Attempted to commit a DataTransaction more than once.")
-        
-        self.isCommitted = true
-        let semaphore = GCDSemaphore(0)
-        self.context.saveAsynchronouslyWithCompletion { (result) -> Void in
-            
-            self.result = result
-            completion(result: result)
-            semaphore.signal()
-        }
-        semaphore.wait()
-    }
-    
-    /**
-    Saves the transaction changes and waits for completion synchronously. Note that this method should not be used after either the commit(_:) or commitAndWait() method was already called once.
-    
-    :returns: a SaveResult value indicating success or failure.
-    */
-    public func commitAndWait() {
-        
-        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to commit a DataTransaction outside a transaction queue.")
-        HardcoreData.assert(!self.isCommitted, "Attempted to commit a DataTransaction more than once.")
-        
-        self.isCommitted = true
-        self.result = self.context.saveSynchronously()
-    }
-    
-    /**
-    Begins a child transaction synchronously where NSManagedObject creates, updates, and deletes can be made.
-    
-    :param: closure the block where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent NSManagedObjectContext.
-    :returns: a SaveResult value indicating success or failure, or nil if the transaction was not comitted synchronously
-    */
-    public func performTransactionAndWait(closure: (transaction: DataTransaction) -> Void) -> SaveResult? {
-        
-        return DataTransaction(
-            mainContext: self.context,
-            queue: self.childTransactionQueue,
-            closure: closure).performAndWait()
-    }
-    
-    
-    // MARK: - Internal
+    // MARK: Internal
     
     internal let context: NSManagedObjectContext
+    internal let transactionQueue: GCDQueue
+    internal let childTransactionQueue: GCDQueue = .createSerial("com.hardcoredata.datastack.childtransactionqueue")
     
-    internal init(mainContext: NSManagedObjectContext, queue: GCDQueue, closure: (transaction: DataTransaction) -> Void) {
+    internal var isCommitted = false
+    internal var result: SaveResult?
+    
+    internal init(mainContext: NSManagedObjectContext, queue: GCDQueue) {
         
         self.transactionQueue = queue
-        self.closure = closure
         
         let context = mainContext.temporaryContextInTransaction(nil)
         self.context = context
@@ -155,30 +111,4 @@ public final class DataTransaction {
         context.retainsRegisteredObjects = true
         context.parentTransaction = self
     }
-    
-    internal func perform() {
-        
-        self.transactionQueue.async {
-            
-            self.closure(transaction: self)
-        }
-    }
-    
-    internal func performAndWait() -> SaveResult? {
-        
-        self.transactionQueue.sync {
-            
-            self.closure(transaction: self)
-        }
-        return self.result
-    }
-    
-    
-    // MARK: - Private
-    
-    private var isCommitted = false
-    private var result: SaveResult?
-    private let transactionQueue: GCDQueue
-    private let closure: (transaction: DataTransaction) -> Void
-    private let childTransactionQueue: GCDQueue = .createSerial("com.hardcoredata.datastack.childtransactionqueue")
 }

HardcoreData/HardcoreData+Transaction.swift

@@ -37,7 +37,7 @@ public extension HardcoreData {
     
     :param: closure the block where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent NSManagedObjectContext.
     */
-    public static func performTransaction(closure: (transaction: DataTransaction) -> Void) {
+    public static func performTransaction(closure: (transaction: AsynchronousDataTransaction) -> Void) {
         
         self.defaultStack.performTransaction(closure)
     }
@@ -48,7 +48,7 @@ public extension HardcoreData {
     :param: closure the block where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent NSManagedObjectContext.
     :returns: a SaveResult value indicating success or failure, or nil if the transaction was not comitted synchronously
     */
-    public static func performTransactionAndWait(closure: (transaction: DataTransaction) -> Void) -> SaveResult? {
+    public static func performTransactionAndWait(closure: (transaction: SynchronousDataTransaction) -> Void) -> SaveResult? {
         
         return self.defaultStack.performTransactionAndWait(closure)
     }

HardcoreData/SynchronousDataTransaction.swift

@@ -0,0 +1,71 @@
+//
+//  SynchronousDataTransaction.swift
+//  HardcoreData
+//
+//  Created by John Rommel Estropia on 2015/02/28.
+//  Copyright (c) 2015 John Rommel Estropia. All rights reserved.
+//
+
+import Foundation
+import GCDKit
+
+public class SynchronousDataTransaction: DataTransaction {
+    
+    // MARK: Public
+    
+    /**
+    Saves the transaction changes and waits for completion synchronously. Note that this method should not be used after either the commit(_:) or commitAndWait() method was already called once.
+    
+    :returns: a SaveResult value indicating success or failure.
+    */
+    public func commitAndWait() {
+        
+        HardcoreData.assert(self.transactionQueue.isCurrentExecutionContext() == true, "Attempted to commit a \(self.dynamicType) outside a transaction queue.")
+        HardcoreData.assert(!self.isCommitted, "Attempted to commit a \(self.dynamicType) more than once.")
+        
+        self.isCommitted = true
+        self.result = self.context.saveSynchronously()
+    }
+    
+    /**
+    Begins a child transaction synchronously where NSManagedObject creates, updates, and deletes can be made.
+    
+    :param: closure the block where creates, updates, and deletes can be made to the transaction. Transaction blocks are executed serially in a background queue, and all changes are made from a concurrent NSManagedObjectContext.
+    :returns: a SaveResult value indicating success or failure, or nil if the transaction was not comitted synchronously
+    */
+    public func performTransactionAndWait(closure: (transaction: SynchronousDataTransaction) -> Void) -> SaveResult? {
+        
+        return SynchronousDataTransaction(
+            mainContext: self.context,
+            queue: self.childTransactionQueue,
+            closure: closure).performAndWait()
+    }
+    
+    
+    // MARK: Internal
+    
+    internal func performAndWait() -> SaveResult? {
+        
+        self.transactionQueue.sync {
+            
+            self.closure(transaction: self)
+            if !self.isCommitted {
+                
+                HardcoreData.log(.Warning, message: "The closure for the \(self.dynamicType) completed without being committed. All changes made within the transaction were discarded.")
+            }
+        }
+        return self.result
+    }
+    
+    internal init(mainContext: NSManagedObjectContext, queue: GCDQueue, closure: (transaction: SynchronousDataTransaction) -> Void) {
+        
+        self.closure = closure
+        
+        super.init(mainContext: mainContext, queue: queue)
+    }
+    
+    
+    // MARK: - Private
+    
+    private let closure: (transaction: SynchronousDataTransaction) -> Void
+}