Flatten file directories (fixes #159)

Sources/SQLiteStore.swift

@@ -0,0 +1,262 @@
+//
+//  SQLiteStore.swift
+//  CoreStore
+//
+//  Copyright © 2016 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 CoreData
+
+
+// MARK: - SQLiteStore
+
+/**
+ A storage interface that is backed by an SQLite database.
+ 
+ - Warning: The default SQLite file location for the `LegacySQLiteStore` and `SQLiteStore` are different. If the app was depending on CoreStore's default directories prior to 2.0.0, make sure to use `LegacySQLiteStore` instead of `SQLiteStore`.
+ */
+public final class SQLiteStore: LocalStorage, DefaultInitializableStore {
+    
+    /**
+     Initializes an SQLite store interface from the given SQLite file URL. When this instance is passed to the `DataStack`'s `addStorage()` methods, a new SQLite file will be created if it does not exist.
+     
+     - parameter fileURL: the local file URL for the target SQLite persistent store. Note that if you have multiple configurations, you will need to specify a different `fileURL` explicitly for each of them.
+     - parameter configuration: an optional configuration name from the model file. If not specified, defaults to `nil`, the "Default" configuration. Note that if you have multiple configurations, you will need to specify a different `fileURL` explicitly for each of them.
+     - parameter mappingModelBundles: a list of `NSBundle`s from which to search mapping models (*.xcmappingmodel) for migration.
+     - parameter localStorageOptions: When the `SQLiteStore` is passed to the `DataStack`'s `addStorage()` methods, tells the `DataStack` how to setup the persistent store. Defaults to `.None`.
+     */
+    public init(fileURL: URL, configuration: String? = nil, mappingModelBundles: [Bundle] = Bundle.allBundles, localStorageOptions: LocalStorageOptions = nil) {
+        
+        self.fileURL = fileURL
+        self.configuration = configuration
+        self.mappingModelBundles = mappingModelBundles
+        self.localStorageOptions = localStorageOptions
+    }
+    
+    /**
+     Initializes an SQLite store interface from the given SQLite file name. When this instance is passed to the `DataStack`'s `addStorage()` methods, a new SQLite file will be created if it does not exist.
+     
+     - Warning: The default SQLite file location for the `LegacySQLiteStore` and `SQLiteStore` are different. If the app was depending on CoreStore's default directories prior to 2.0.0, make sure to use `LegacySQLiteStore` instead of `SQLiteStore`.
+     - parameter fileName: the local filename for the SQLite persistent store in the "Application Support/<bundle id>" directory (or the "Caches/<bundle id>" directory on tvOS). Note that if you have multiple configurations, you will need to specify a different `fileName` explicitly for each of them.
+     - parameter configuration: an optional configuration name from the model file. If not specified, defaults to `nil`, the "Default" configuration. Note that if you have multiple configurations, you will need to specify a different `fileName` explicitly for each of them.
+     - parameter mappingModelBundles: a list of `NSBundle`s from which to search mapping models (*.xcmappingmodel) for migration
+     - parameter localStorageOptions: When the `SQLiteStore` is passed to the `DataStack`'s `addStorage()` methods, tells the `DataStack` how to setup the persistent store. Defaults to `.None`.
+     */
+    public init(fileName: String, configuration: String? = nil, mappingModelBundles: [Bundle] = Bundle.allBundles, localStorageOptions: LocalStorageOptions = nil) {
+        
+        self.fileURL = SQLiteStore.defaultRootDirectory
+            .appendingPathComponent(fileName, isDirectory: false)
+        self.configuration = configuration
+        self.mappingModelBundles = mappingModelBundles
+        self.localStorageOptions = localStorageOptions
+    }
+    
+    
+    // MARK: DefaultInitializableStore
+    
+    /**
+     Initializes an `SQLiteStore` with an all-default settings: a `fileURL` pointing to a "<Application name>.sqlite" file in the "Application Support/<bundle id>" directory (or the "Caches/<bundle id>" directory on tvOS), a `nil` `configuration` pertaining to the "Default" configuration, a `mappingModelBundles` set to search all `NSBundle`s, and `localStorageOptions` set to `.AllowProgresiveMigration`.
+     
+     - Warning: The default SQLite file location for the `LegacySQLiteStore` and `SQLiteStore` are different. If the app was depending on CoreStore's default directories prior to 2.0.0, make sure to use `LegacySQLiteStore` instead of `SQLiteStore`.
+     */
+    public init() {
+        
+        self.fileURL = SQLiteStore.defaultFileURL
+        self.configuration = nil
+        self.mappingModelBundles = Bundle.allBundles
+        self.localStorageOptions = nil
+    }
+    
+    
+    // MARK: StorageInterface
+    
+    /**
+     The string identifier for the `NSPersistentStore`'s `type` property. For `SQLiteStore`s, this is always set to `NSSQLiteStoreType`.
+     */
+    public static let storeType = NSSQLiteStoreType
+    
+    /**
+     The configuration name in the model file
+     */
+    public let configuration: String?
+    
+    /**
+     The options dictionary for the `NSPersistentStore`. For `SQLiteStore`s, this is always set to 
+     ```
+     [NSSQLitePragmasOption: ["journal_mode": "WAL"]]
+     ```
+     */
+    public let storeOptions: [AnyHashable: Any]? = [NSSQLitePragmasOption: ["journal_mode": "WAL"]]
+    
+    /**
+     Do not call directly. Used by the `DataStack` internally.
+     */
+    public func didAddToDataStack(_ dataStack: DataStack) {
+        
+        self.dataStack = dataStack
+    }
+    
+    /**
+     Do not call directly. Used by the `DataStack` internally.
+     */
+    public func didRemoveFromDataStack(_ dataStack: DataStack) {
+        
+        self.dataStack = nil
+    }
+    
+    
+    // MAKR: LocalStorage
+    
+    /**
+     The `NSURL` that points to the SQLite file
+     */
+    public let fileURL: URL
+    
+    /**
+     The `NSBundle`s from which to search mapping models for migrations
+     */
+    public let mappingModelBundles: [Bundle]
+    
+    /**
+     Options that tell the `DataStack` how to setup the persistent store
+     */
+    public var localStorageOptions: LocalStorageOptions
+    
+    /**
+     The options dictionary for the specified `LocalStorageOptions`
+     */
+    public func dictionary(forOptions options: LocalStorageOptions) -> [AnyHashable: Any]? {
+        
+        if options == .none {
+            
+            return self.storeOptions
+        }
+        
+        var storeOptions = self.storeOptions ?? [:]
+        if options.contains(.allowSynchronousLightweightMigration) {
+            
+            storeOptions[NSMigratePersistentStoresAutomaticallyOption] = true
+            storeOptions[NSInferMappingModelAutomaticallyOption] = true
+        }
+        return storeOptions
+    }
+    
+    /**
+     Called by the `DataStack` to perform actual deletion of the store file from disk. Do not call directly! The `sourceModel` argument is a hint for the existing store's model version. For `SQLiteStore`, this converts the database's WAL journaling mode to DELETE before deleting the file.
+     */
+    public func eraseStorageAndWait(metadata: [String: Any], soureModelHint: NSManagedObjectModel?) throws {
+        
+        // TODO: check if attached to persistent store
+        
+        func deleteFiles(storeURL: URL, extraFiles: [String] = []) throws {
+            
+            let fileManager = FileManager.default
+            let extraFiles: [String] = [
+                storeURL.path.appending("-wal"),
+                storeURL.path.appending("-shm")
+            ]
+            do {
+                
+                let trashURL = URL(fileURLWithPath: NSSearchPathForDirectoriesInDomains(.cachesDirectory, .userDomainMask, true).first!)
+                    .appendingPathComponent(Bundle.main.bundleIdentifier ?? "com.CoreStore.DataStack", isDirectory: true)
+                    .appendingPathComponent("trash", isDirectory: true)
+                try fileManager.createDirectory(
+                    at: trashURL,
+                    withIntermediateDirectories: true,
+                    attributes: nil
+                )
+                
+                let temporaryFileURL = trashURL.appendingPathComponent(UUID().uuidString, isDirectory: false)
+                try fileManager.moveItem(at: storeURL, to: temporaryFileURL)
+                
+                let extraTemporaryFiles = extraFiles.map { (extraFile) -> String in
+                    
+                    let temporaryFile = trashURL.appendingPathComponent(UUID().uuidString, isDirectory: false).path
+                    if let _ = try? fileManager.moveItem(atPath: extraFile, toPath: temporaryFile) {
+                        
+                        return temporaryFile
+                    }
+                    return extraFile
+                }
+                DispatchQueue.global(qos: .background).async {
+                    
+                    _ = try? fileManager.removeItem(at: temporaryFileURL)
+                    extraTemporaryFiles.forEach({ _ = try? fileManager.removeItem(atPath: $0) })
+                }
+            }
+            catch {
+                
+                try fileManager.removeItem(at: storeURL)
+                extraFiles.forEach({ _ = try? fileManager.removeItem(atPath: $0) })
+            }
+        }
+        
+        let fileURL = self.fileURL
+        try autoreleasepool {
+            
+            if let soureModel = soureModelHint ?? NSManagedObjectModel.mergedModel(from: nil, forStoreMetadata: metadata) {
+                
+                let journalUpdatingCoordinator = NSPersistentStoreCoordinator(managedObjectModel: soureModel)
+                let store = try journalUpdatingCoordinator.addPersistentStore(
+                    ofType: type(of: self).storeType,
+                    configurationName: self.configuration,
+                    at: fileURL,
+                    options: [NSSQLitePragmasOption: ["journal_mode": "DELETE"]]
+                )
+                try journalUpdatingCoordinator.remove(store)
+            }
+            try deleteFiles(storeURL: fileURL)
+        }
+    }
+    
+    
+    // MARK: Internal
+    
+    internal static let defaultRootDirectory: URL = {
+        
+        #if os(tvOS)
+            let systemDirectorySearchPath = FileManager.SearchPathDirectory.cachesDirectory
+        #else
+            let systemDirectorySearchPath = FileManager.SearchPathDirectory.applicationSupportDirectory
+        #endif
+        
+        let defaultSystemDirectory = FileManager.default.urls(
+                for: systemDirectorySearchPath,
+                in: .userDomainMask).first!
+        
+        return defaultSystemDirectory.appendingPathComponent(
+            Bundle.main.bundleIdentifier ?? "com.CoreStore.DataStack",
+            isDirectory: true
+        )
+    }()
+    
+    internal static let defaultFileURL = SQLiteStore.defaultRootDirectory
+        .appendingPathComponent(
+            (Bundle.main.object(forInfoDictionaryKey: "CFBundleName") as? String) ?? "CoreData",
+            isDirectory: false
+        )
+        .appendingPathExtension("sqlite")
+    
+    
+    // MARK: Private
+    
+    private weak var dataStack: DataStack?
+}