Files
CoreStore/Sources/Transformable.swift
2019-01-31 16:50:43 +09:00

578 lines
26 KiB
Swift

//
// Transformable.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 CoreData
import Foundation
// MARK: - DynamicObject
extension DynamicObject where Self: CoreStoreObject {
/**
The containing type for transformable properties. `Transformable` properties support types that conforms to `NSCoding & NSCopying`.
```
class Animal: CoreStoreObject {
let species = Value.Required<String>("species", initial: "")
let nickname = Value.Optional<String>("nickname")
let color = Transformable.Optional<UIColor>("color")
}
```
- Important: `Transformable` properties are required to be stored properties. Computed properties will be ignored, including `lazy` and `weak` properties.
*/
public typealias Transformable = TransformableContainer<Self>
}
// MARK: - TransformableContainer
/**
The containing type for transformable properties. Use the `DynamicObject.Transformable` typealias instead for shorter syntax.
```
class Animal: CoreStoreObject {
let species = Value.Required<String>("species", initial: "")
let nickname = Value.Optional<String>("nickname")
let color = Transformable.Optional<UIColor>("color")
}
```
*/
public enum TransformableContainer<O: CoreStoreObject> {
// MARK: - Required
/**
The containing type for transformable properties. Any type that conforms to `NSCoding & NSCopying` are supported.
```
class Animal: CoreStoreObject {
let species = Value.Required<String>("species", initial: "")
let nickname = Value.Optional<String>("nickname")
let color = Transformable.Optional<UIColor>("color")
}
```
- Important: `Transformable.Required` properties are required to be stored properties. Computed properties will be ignored, including `lazy` and `weak` properties.
*/
public final class Required<V: NSCoding & NSCopying>: AttributeProtocol {
/**
Initializes the metadata for the property.
```
class Animal: CoreStoreObject {
let species = Value.Required<String>("species", initial: "")
let color = Transformable.Required<UIColor>(
"color",
initial: UIColor.clear,
isTransient: true,
customGetter: Animal.getColor(_:)
)
}
private static func getColor(_ partialObject: PartialObject<Animal>) -> UIColor {
let cachedColor = partialObject.primitiveValue(for: { $0.color })
if cachedColor != UIColor.clear {
return cachedColor
}
let color: UIColor
switch partialObject.value(for: { $0.species }) {
case "Swift": color = UIColor.orange
case "Bulbasaur": color = UIColor.green
default: color = UIColor.black
}
partialObject.setPrimitiveValue(color, for: { $0.color })
return color
}
```
- parameter keyPath: the permanent attribute name for this property.
- parameter initial: the initial value for the property when the object is first created. Defaults to the `ImportableAttributeType`'s empty value if not specified.
- parameter isTransient: `true` if the property is transient, otherwise `false`. Defaults to `false` if not specified. The transient flag specifies whether or not a property's value is ignored when an object is saved to a persistent store. Transient properties are not saved to the persistent store, but are still managed for undo, redo, validation, and so on.
- parameter allowsExternalBinaryDataStorage: `true` if the attribute allows external binary storage, otherwise `false`.
- parameter versionHashModifier: used to mark or denote a property as being a different "version" than another even if all of the values which affect persistence are equal. (Such a difference is important in cases where the properties are unchanged but the format or content of its data are changed.)
- parameter renamingIdentifier: used to resolve naming conflicts between models. When creating an entity mapping between entities in two managed object models, a source entity property and a destination entity property that share the same identifier indicate that a property mapping should be configured to migrate from the source to the destination. If unset, the identifier will be the property's name.
- parameter customGetter: use this closure as an "override" for the default property getter. The closure receives a `PartialObject<O>`, which acts as a fast, type-safe KVC interface for `CoreStoreObject`. The reason a `CoreStoreObject` instance is not passed directly is because the Core Data runtime is not aware of `CoreStoreObject` properties' static typing, and so loading those info everytime KVO invokes this accessor method incurs a cumulative performance hit (especially in KVO-heavy operations such as `ListMonitor` observing.) When accessing the property value from `PartialObject<O>`, make sure to use `PartialObject<O>.primitiveValue(for:)` instead of `PartialObject<O>.value(for:)`, which would unintentionally execute the same closure again recursively.
- parameter customSetter: use this closure as an "override" for the default property setter. The closure receives a `PartialObject<O>`, which acts as a fast, type-safe KVC interface for `CoreStoreObject`. The reason a `CoreStoreObject` instance is not passed directly is because the Core Data runtime is not aware of `CoreStoreObject` properties' static typing, and so loading those info everytime KVO invokes this accessor method incurs a cumulative performance hit (especially in KVO-heavy operations such as `ListMonitor` observing.) When accessing the property value from `PartialObject<O>`, make sure to use `PartialObject<O>.setPrimitiveValue(_:for:)` instead of `PartialObject<O>.setValue(_:for:)`, which would unintentionally execute the same closure again recursively.
- parameter affectedByKeyPaths: a set of key paths for properties whose values affect the value of the receiver. This is similar to `NSManagedObject.keyPathsForValuesAffectingValue(forKey:)`.
*/
public init(
_ keyPath: KeyPathString,
initial: @autoclosure @escaping () -> V,
isTransient: Bool = false,
allowsExternalBinaryDataStorage: Bool = false,
versionHashModifier: @autoclosure @escaping () -> String? = nil,
renamingIdentifier: @autoclosure @escaping () -> String? = nil,
customGetter: ((_ partialObject: PartialObject<O>) -> V)? = nil,
customSetter: ((_ partialObject: PartialObject<O>, _ newValue: V) -> Void)? = nil,
affectedByKeyPaths: @autoclosure @escaping () -> Set<String> = []) {
self.keyPath = keyPath
self.defaultValue = initial
self.isTransient = isTransient
self.allowsExternalBinaryDataStorage = allowsExternalBinaryDataStorage
self.versionHashModifier = versionHashModifier
self.renamingIdentifier = renamingIdentifier
self.customGetter = customGetter
self.customSetter = customSetter
self.affectedByKeyPaths = affectedByKeyPaths
}
/**
The property value.
*/
public var value: V {
get {
CoreStore.assert(
self.rawObject != nil,
"Attempted to access values from a \(cs_typeName(O.self)) meta object. Meta objects are only used for querying keyPaths and infering types."
)
return withExtendedLifetime(self.rawObject!) { (object) in
CoreStore.assert(
object.isRunningInAllowedQueue() == true,
"Attempted to access \(cs_typeName(O.self))'s value outside it's designated queue."
)
if let customGetter = self.customGetter {
return customGetter(PartialObject<O>(object))
}
return object.value(forKey: self.keyPath)! as! V
}
}
set {
CoreStore.assert(
self.rawObject != nil,
"Attempted to access values from a \(cs_typeName(O.self)) meta object. Meta objects are only used for querying keyPaths and infering types."
)
return withExtendedLifetime(self.rawObject!) { (object) in
CoreStore.assert(
object.isRunningInAllowedQueue() == true,
"Attempted to access \(cs_typeName(O.self))'s value outside it's designated queue."
)
CoreStore.assert(
object.isEditableInContext() == true,
"Attempted to update a \(cs_typeName(O.self))'s value from outside a transaction."
)
if let customSetter = self.customSetter {
return customSetter(PartialObject<O>(object), newValue)
}
object.setValue(
newValue,
forKey: self.keyPath
)
}
}
}
// MARK: AttributeProtocol
internal static var attributeType: NSAttributeType {
return .transformableAttributeType
}
internal let keyPath: KeyPathString
internal let isOptional = false
internal let isTransient: Bool
internal let allowsExternalBinaryDataStorage: Bool
internal let versionHashModifier: () -> String?
internal let renamingIdentifier: () -> String?
internal let defaultValue: () -> Any?
internal let affectedByKeyPaths: () -> Set<String>
internal var rawObject: CoreStoreManagedObject?
internal private(set) lazy var getter: CoreStoreManagedObject.CustomGetter? = cs_lazy { [unowned self] in
guard let customGetter = self.customGetter else {
return nil
}
let keyPath = self.keyPath
return { (_ id: Any) -> Any? in
let rawObject = id as! CoreStoreManagedObject
rawObject.willAccessValue(forKey: keyPath)
defer {
rawObject.didAccessValue(forKey: keyPath)
}
let value = customGetter(PartialObject<O>(rawObject))
return value
}
}
internal private(set) lazy var setter: CoreStoreManagedObject.CustomSetter? = cs_lazy { [unowned self] in
guard let customSetter = self.customSetter else {
return nil
}
let keyPath = self.keyPath
return { (_ id: Any, _ newValue: Any?) -> Void in
let rawObject = id as! CoreStoreManagedObject
rawObject.willChangeValue(forKey: keyPath)
defer {
rawObject.didChangeValue(forKey: keyPath)
}
customSetter(
PartialObject<O>(rawObject),
newValue as! V
)
}
}
// MARK: Private
private let customGetter: ((_ partialObject: PartialObject<O>) -> V)?
private let customSetter: ((_ partialObject: PartialObject<O>, _ newValue: V) -> Void)?
// MARK: Deprecated
@available(*, unavailable, message: "Indexes are now set through the Entity<T> initializer, which now supports compound indexes.")
public convenience init(
_ keyPath: KeyPathString,
initial: @autoclosure @escaping () -> V,
isIndexed: Bool,
isTransient: Bool = false,
allowsExternalBinaryDataStorage: Bool = false,
versionHashModifier: @autoclosure @escaping () -> String? = nil,
renamingIdentifier: @autoclosure @escaping () -> String? = nil,
customGetter: ((_ partialObject: PartialObject<O>) -> V)? = nil,
customSetter: ((_ partialObject: PartialObject<O>, _ newValue: V) -> Void)? = nil,
affectedByKeyPaths: @autoclosure @escaping () -> Set<String> = []) {
fatalError()
}
}
// MARK: - Optional
/**
The containing type for optional transformable properties. Any type that conforms to `NSCoding & NSCopying` are supported.
```
class Animal: CoreStoreObject {
let species = Value.Required<String>("species", initial: "")
let nickname = Value.Optional<String>("nickname")
let color = Transformable.Optional<UIColor>("color")
}
```
- Important: `Transformable.Optional` properties are required to be stored properties. Computed properties will be ignored, including `lazy` and `weak` properties.
*/
public final class Optional<V: NSCoding & NSCopying>: AttributeProtocol {
/**
Initializes the metadata for the property.
```
class Animal: CoreStoreObject {
let species = Value.Required<String>("species", initial: "")
let color = Transformable.Optional<UIColor>(
"color",
isTransient: true,
customGetter: Animal.getColor(_:)
)
}
private static func getColor(_ partialObject: PartialObject<Animal>) -> UIColor? {
if let cachedColor = partialObject.primitiveValue(for: { $0.color }) {
return cachedColor
}
let color: UIColor?
switch partialObject.value(for: { $0.species }) {
case "Swift": color = UIColor.orange
case "Bulbasaur": color = UIColor.green
default: return nil
}
partialObject.setPrimitiveValue(color, for: { $0.color })
return color
}
```
- parameter keyPath: the permanent attribute name for this property.
- parameter initial: the initial value for the property when the object is first created. Defaults to the `ImportableAttributeType`'s empty value if not specified.
- parameter isTransient: `true` if the property is transient, otherwise `false`. Defaults to `false` if not specified. The transient flag specifies whether or not a property's value is ignored when an object is saved to a persistent store. Transient properties are not saved to the persistent store, but are still managed for undo, redo, validation, and so on.
- parameter allowsExternalBinaryDataStorage: `true` if the attribute allows external binary storage, otherwise `false`.
- parameter versionHashModifier: used to mark or denote a property as being a different "version" than another even if all of the values which affect persistence are equal. (Such a difference is important in cases where the properties are unchanged but the format or content of its data are changed.)
- parameter renamingIdentifier: used to resolve naming conflicts between models. When creating an entity mapping between entities in two managed object models, a source entity property and a destination entity property that share the same identifier indicate that a property mapping should be configured to migrate from the source to the destination. If unset, the identifier will be the property's name.
- parameter customGetter: use this closure as an "override" for the default property getter. The closure receives a `PartialObject<O>`, which acts as a fast, type-safe KVC interface for `CoreStoreObject`. The reason a `CoreStoreObject` instance is not passed directly is because the Core Data runtime is not aware of `CoreStoreObject` properties' static typing, and so loading those info everytime KVO invokes this accessor method incurs a cumulative performance hit (especially in KVO-heavy operations such as `ListMonitor` observing.) When accessing the property value from `PartialObject<O>`, make sure to use `PartialObject<O>.primitiveValue(for:)` instead of `PartialObject<O>.value(for:)`, which would unintentionally execute the same closure again recursively.
- parameter customSetter: use this closure as an "override" for the default property setter. The closure receives a `PartialObject<O>`, which acts as a fast, type-safe KVC interface for `CoreStoreObject`. The reason a `CoreStoreObject` instance is not passed directly is because the Core Data runtime is not aware of `CoreStoreObject` properties' static typing, and so loading those info everytime KVO invokes this accessor method incurs a cumulative performance hit (especially in KVO-heavy operations such as `ListMonitor` observing.) When accessing the property value from `PartialObject<O>`, make sure to use `PartialObject<O>.setPrimitiveValue(_:for:)` instead of `PartialObject<O>.setValue(_:for:)`, which would unintentionally execute the same closure again recursively.
- parameter affectedByKeyPaths: a set of key paths for properties whose values affect the value of the receiver. This is similar to `NSManagedObject.keyPathsForValuesAffectingValue(forKey:)`.
*/
public init(
_ keyPath: KeyPathString,
initial: @autoclosure @escaping () -> V? = nil,
isTransient: Bool = false,
allowsExternalBinaryDataStorage: Bool = false,
versionHashModifier: @autoclosure @escaping () -> String? = nil,
renamingIdentifier: @autoclosure @escaping () -> String? = nil,
customGetter: ((_ partialObject: PartialObject<O>) -> V?)? = nil,
customSetter: ((_ partialObject: PartialObject<O>, _ newValue: V?) -> Void)? = nil,
affectedByKeyPaths: @autoclosure @escaping () -> Set<String> = []) {
self.keyPath = keyPath
self.defaultValue = initial
self.isTransient = isTransient
self.allowsExternalBinaryDataStorage = allowsExternalBinaryDataStorage
self.versionHashModifier = versionHashModifier
self.renamingIdentifier = renamingIdentifier
self.customGetter = customGetter
self.customSetter = customSetter
self.affectedByKeyPaths = affectedByKeyPaths
}
/**
The property value.
*/
public var value: V? {
get {
CoreStore.assert(
self.rawObject != nil,
"Attempted to access values from a \(cs_typeName(O.self)) meta object. Meta objects are only used for querying keyPaths and infering types."
)
return withExtendedLifetime(self.rawObject!) { (object) in
CoreStore.assert(
object.isRunningInAllowedQueue() == true,
"Attempted to access \(cs_typeName(O.self))'s value outside it's designated queue."
)
if let customGetter = self.customGetter {
return customGetter(PartialObject<O>(object))
}
return object.value(forKey: self.keyPath) as! V?
}
}
set {
CoreStore.assert(
self.rawObject != nil,
"Attempted to access values from a \(cs_typeName(O.self)) meta object. Meta objects are only used for querying keyPaths and infering types."
)
return withExtendedLifetime(self.rawObject!) { (object) in
CoreStore.assert(
object.isRunningInAllowedQueue() == true,
"Attempted to access \(cs_typeName(O.self))'s value outside it's designated queue."
)
CoreStore.assert(
object.isEditableInContext() == true,
"Attempted to update a \(cs_typeName(O.self))'s value from outside a transaction."
)
if let customSetter = self.customSetter {
return customSetter(PartialObject<O>(object), newValue)
}
object.setValue(
newValue,
forKey: self.keyPath
)
}
}
}
// MARK: AttributeProtocol
internal static var attributeType: NSAttributeType {
return .transformableAttributeType
}
internal let keyPath: KeyPathString
internal let isOptional = true
internal let isTransient: Bool
internal let allowsExternalBinaryDataStorage: Bool
internal let versionHashModifier: () -> String?
internal let renamingIdentifier: () -> String?
internal let defaultValue: () -> Any?
internal let affectedByKeyPaths: () -> Set<String>
internal var rawObject: CoreStoreManagedObject?
internal private(set) lazy var getter: CoreStoreManagedObject.CustomGetter? = cs_lazy { [unowned self] in
guard let customGetter = self.customGetter else {
return nil
}
let keyPath = self.keyPath
return { (_ id: Any) -> Any? in
let rawObject = id as! CoreStoreManagedObject
rawObject.willAccessValue(forKey: keyPath)
defer {
rawObject.didAccessValue(forKey: keyPath)
}
let value = customGetter(PartialObject<O>(rawObject))
return value
}
}
internal private(set) lazy var setter: CoreStoreManagedObject.CustomSetter? = cs_lazy { [unowned self] in
guard let customSetter = self.customSetter else {
return nil
}
let keyPath = self.keyPath
return { (_ id: Any, _ newValue: Any?) -> Void in
let rawObject = id as! CoreStoreManagedObject
rawObject.willChangeValue(forKey: keyPath)
defer {
rawObject.didChangeValue(forKey: keyPath)
}
customSetter(
PartialObject<O>(rawObject),
newValue as! V?
)
}
}
// MARK: Private
private let customGetter: ((_ partialObject: PartialObject<O>) -> V?)?
private let customSetter: ((_ partialObject: PartialObject<O>, _ newValue: V?) -> Void)?
// MARK: Deprecated
@available(*, unavailable, message: "Indexes are now set through the Entity<T> initializer, which now supports compound indexes.")
public convenience init(
_ keyPath: KeyPathString,
initial: @autoclosure @escaping () -> V? = nil,
isIndexed: Bool,
isTransient: Bool = false,
allowsExternalBinaryDataStorage: Bool = false,
versionHashModifier: @autoclosure @escaping () -> String? = nil,
renamingIdentifier: @autoclosure @escaping () -> String? = nil,
customGetter: ((_ partialObject: PartialObject<O>) -> V?)? = nil,
customSetter: ((_ partialObject: PartialObject<O>, _ newValue: V?) -> Void)? = nil,
affectedByKeyPaths: @autoclosure @escaping () -> Set<String> = []) {
fatalError()
}
}
}
// MARK: - Operations
infix operator .= : AssignmentPrecedence
infix operator .== : ComparisonPrecedence
extension TransformableContainer.Required {
/**
Assigns a transformable value to the property. The operation
```
animal.color .= UIColor.red
```
is equivalent to
```
animal.color.value = UIColor.red
```
*/
public static func .= (_ property: TransformableContainer<O>.Required<V>, _ newValue: V) {
property.value = newValue
}
/**
Assigns a transformable value from another property. The operation
```
animal.nickname .= anotherAnimal.species
```
is equivalent to
```
animal.nickname.value = anotherAnimal.species.value
```
*/
public static func .= <O2>(_ property: TransformableContainer<O>.Required<V>, _ property2: TransformableContainer<O2>.Required<V>) {
property.value = property2.value
}
}
extension TransformableContainer.Optional {
/**
Assigns an optional transformable value to the property. The operation
```
animal.color .= UIColor.red
```
is equivalent to
```
animal.color.value = UIColor.red
```
*/
public static func .= (_ property: TransformableContainer<O>.Optional<V>, _ newValue: V?) {
property.value = newValue
}
/**
Assigns an optional transformable value from another property. The operation
```
animal.color .= anotherAnimal.color
```
is equivalent to
```
animal.color.value = anotherAnimal.color.value
```
*/
public static func .= <O2>(_ property: TransformableContainer<O>.Optional<V>, _ property2: TransformableContainer<O2>.Optional<V>) {
property.value = property2.value
}
/**
Assigns a transformable value from another property. The operation
```
animal.color .= anotherAnimal.color
```
is equivalent to
```
animal.color.value = anotherAnimal.color.value
```
*/
public static func .= <O2>(_ property: TransformableContainer<O>.Optional<V>, _ property2: TransformableContainer<O2>.Required<V>) {
property.value = property2.value
}
}