Added option to encode null values

JSONCodable.playground/Contents.swift

@@ -31,14 +31,14 @@ We'll add conformance to `JSONEncodable`. You may also add conformance to `JSONC
 */
 
 extension User: JSONEncodable {
-    func toJSON() throws -> AnyObject {
-        return try JSONEncoder.create({ (encoder) -> Void in
+    func toJSON(options: JSONEncodingOptions) throws -> AnyObject {
+        return try JSONEncoder.create(options) { (encoder) -> Void in
             try encoder.encode(id, key: "id")
             try encoder.encode(name, key: "full_name")
             try encoder.encode(email, key: "email")
             try encoder.encode(company, key: "company")
             try encoder.encode(friends, key: "friends")
-        })
+        }
     }
 }
 
@@ -54,31 +54,21 @@ We'll add conformance to `JSONDecodable`. You may also add conformance to `JSONC
 */
 
 extension User: JSONDecodable {
-    init?(JSONDictionary: JSONObject) {
-        let decoder = JSONDecoder(object: JSONDictionary)
-        do {
-            id = try decoder.decode("id")
-            name = try decoder.decode("full_name")
-            email = try decoder.decode("email")
-            company = try decoder.decode("company")
-            friends = try decoder.decode("friends")
-        }
-        catch {
-            return nil
-        }
+    init(object: JSONObject) throws {
+        let decoder = JSONDecoder(object: object)
+        id = try decoder.decode("id")
+        name = try decoder.decode("full_name")
+        email = try decoder.decode("email")
+        company = try decoder.decode("company")
+        friends = try decoder.decode("friends")
     }
 }
 
 extension Company: JSONDecodable {
-    init?(JSONDictionary: JSONObject) {
-        let decoder = JSONDecoder(object: JSONDictionary)
-        do {
-            name = try decoder.decode("name")
-            address = try decoder.decode("address")
-        }
-        catch {
-            return nil
-        }
+    init(object: JSONObject) throws {
+        let decoder = JSONDecoder(object: object)
+        name = try decoder.decode("name")
+        address = try decoder.decode("address")
     }
 }
 
@@ -115,7 +105,7 @@ We can instantiate `User` using one of provided initializers:
 - `init?(JSONString: String)`
 */
 
-let user = User(JSONDictionary: JSON)!
+var user = try! User(object: JSON)
 
 print("Decoded: \n\(user)\n\n")
 
@@ -126,7 +116,7 @@ And encode it to JSON using one of the provided methods:
 */
 
 do {
-    let dict = try user.toJSON()
+    let dict = try user.toJSON([])
     print("Encoded: \n\(dict as! JSONObject)\n\n")
 }
 catch {

JSONCodable.playground/contents.xcplayground

@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
-<playground version='5.0' target-platform='osx' requires-full-environment='true' display-mode='rendered'>
+<playground version='5.0' target-platform='osx' display-mode='rendered'>
     <timeline fileName='timeline.xctimeline'/>
 </playground>

JSONCodable.playground/timeline.xctimeline

@@ -2,5 +2,10 @@
 <Timeline
    version = "3.0">
    <TimelineItems>
+      <LoggerValueHistoryTimelineItem
+         documentLocation = "#CharacterRangeLen=46&amp;CharacterRangeLoc=1785&amp;EndingColumnNumber=51&amp;EndingLineNumber=78&amp;StartingColumnNumber=5&amp;StartingLineNumber=78&amp;Timestamp=474577879.680475"
+         selectedRepresentationIndex = "0"
+         shouldTrackSuperviewWidth = "NO">
+      </LoggerValueHistoryTimelineItem>
    </TimelineItems>
 </Timeline>

JSONCodable/JSONCodable.swift

@@ -19,9 +19,10 @@ extension Double: JSONCompatible {}
 extension Float: JSONCompatible {}
 extension Bool: JSONCompatible {}
 extension Int: JSONCompatible {}
+extension NSNull: JSONCompatible {}
 
 extension JSONCompatible {
-    public func toJSON() throws -> AnyObject {
+    public func toJSON(options: JSONEncodingOptions) throws -> AnyObject {
         return self as! AnyObject
     }
 }

JSONCodable/JSONEncodable.swift

@@ -42,21 +42,28 @@ public enum JSONEncodableError: ErrorType, CustomStringConvertible {
     }
 }
 
-// Struct -> Dictionary
+public struct JSONEncodingOptions: OptionSetType {
+    public let rawValue: Int
+    public init(rawValue: Int) {
+        self.rawValue = rawValue;
+    }
+    public static let EncodeNulls  = JSONEncodingOptions(rawValue: 1 << 0)
+}
 
 public protocol JSONEncodable {
-    func toJSON() throws -> AnyObject
+    func toJSON(options: JSONEncodingOptions) throws -> AnyObject
 }
 
 public extension JSONEncodable {
-    func toJSON() throws -> AnyObject {
+
+    func toJSON(options: JSONEncodingOptions) throws -> AnyObject {
         let mirror = Mirror(reflecting: self)
 
         guard let style = mirror.displayStyle where style == .Struct || style == .Class else {
             throw JSONEncodableError.IncompatibleTypeError(elementType: self.dynamicType)
         }
 
-        return try JSONEncoder.create({ (encoder) -> Void in
+        return try JSONEncoder.create(options) { (encoder) -> Void in
             // loop through all properties (instance variables)
             for (labelMaybe, valueMaybe) in mirror.children {
                 guard let label = labelMaybe else {
@@ -87,18 +94,18 @@ public extension JSONEncodable {
                     throw JSONEncodableError.ChildIncompatibleTypeError(key: label, elementType: value.dynamicType)
                 }
             }
-        })
+        }
     }
 }
 
 public extension Array {//where Element: JSONEncodable {
     private var wrapped: [Any] { return self.map{$0} }
 
-    public func toJSON() throws -> AnyObject {
+    public func toJSON(options: JSONEncodingOptions) throws -> AnyObject {
         var results: [AnyObject] = []
         for item in self.wrapped {
             if let item = item as? JSONEncodable {
-                results.append(try item.toJSON())
+                results.append(try item.toJSON(options))
             }
             else {
                 throw JSONEncodableError.ArrayIncompatibleTypeError(elementType: item.dynamicType)
@@ -111,11 +118,11 @@ public extension Array {//where Element: JSONEncodable {
 // Dictionary convenience methods
 
 public extension Dictionary {//where Key: String, Value: JSONEncodable {
-    public func toJSON() throws -> AnyObject {
+    public func toJSON(options: JSONEncodingOptions) throws -> AnyObject {
         var result: [String: AnyObject] = [:]
         for (k, item) in self {
             if let item = item as? JSONEncodable {
-                result[String(k)] = try item.toJSON()
+                result[String(k)] = try item.toJSON(options)
             }
             else {
                 throw JSONEncodableError.DictionaryIncompatibleTypeError(elementType: item.dynamicType)
@@ -129,9 +136,11 @@ public extension Dictionary {//where Key: String, Value: JSONEncodable {
 
 public class JSONEncoder {
     var object = JSONObject()
+    public var options: JSONEncodingOptions = []
 
-    public static func create(@noescape setup: (encoder: JSONEncoder) throws -> Void) rethrows -> JSONObject {
+    public static func create(options: JSONEncodingOptions, @noescape setup: (encoder: JSONEncoder) throws -> Void) rethrows -> JSONObject {
         let encoder = JSONEncoder()
+        encoder.options = options
         try setup(encoder: encoder)
         return encoder.object
     }
@@ -145,21 +154,18 @@ public class JSONEncoder {
     */
 
     // JSONEncodable
-    public func encode<Encodable: JSONEncodable>(value: Encodable, key: String) throws {
-        let result = try value.toJSON()
-        object[key] = result
-    }
-    private func encode(value: JSONEncodable, key: String) throws {
-        let result = try value.toJSON()
+    public func encode(value: JSONEncodable, key: String) throws {
+        let result = try value.toJSON(options)
         object[key] = result
     }
 
     // JSONEncodable?
     public func encode<Encodable: JSONEncodable>(value: Encodable?, key: String) throws {
         guard let actual = value else {
+            if options.contains(.EncodeNulls) { object[key] = NSNull() }
             return
         }
-        let result = try actual.toJSON()
+        let result = try actual.toJSON(options)
         object[key] = result
     }
 
@@ -168,116 +174,96 @@ public class JSONEncoder {
         guard let compatible = value.rawValue as? JSONCompatible else {
             return
         }
-        let result = try compatible.toJSON()
+        let result = try compatible.toJSON(options)
         object[key] = result
     }
 
     // Enum?
     public func encode<Enum: RawRepresentable>(value: Enum?, key: String) throws {
         guard let actual = value else {
+            if options.contains(.EncodeNulls) { object[key] = NSNull() }
             return
         }
         guard let compatible = actual.rawValue as? JSONCompatible else {
             return
         }
-        let result = try compatible.toJSON()
+        let result = try compatible.toJSON(options)
         object[key] = result
     }
 
     // [JSONEncodable]
     public func encode<Encodable: JSONEncodable>(array: [Encodable], key: String) throws {
-        guard array.count > 0 else {
-            return
-        }
-        let result = try array.toJSON()
+        let result = try array.toJSON(options)
         object[key] = result
     }
     public func encode(array: [JSONEncodable], key: String) throws {
-        guard array.count > 0 else {
-            return
-        }
-        let result = try array.toJSON()
+        let result = try array.toJSON(options)
         object[key] = result
     }
-    private func encode(array: JSONArray, key: String) throws {
-        guard array.count > 0 && array.elementsAreJSONEncodable() else {
+    func encode(array: JSONArray, key: String) throws {
+        guard array.elementsAreJSONEncodable() else {
             return
         }
         let encodable = array.elementsMadeJSONEncodable()
-        let result = try encodable.toJSON()
+        let result = try encodable.toJSON(options)
         object[key] = result
     }
 
     // [JSONEncodable]?
     public func encode<Encodable: JSONEncodable>(value: [Encodable]?, key: String) throws {
         guard let actual = value else {
+            if options.contains(.EncodeNulls) { object[key] = NSNull() }
             return
         }
-        guard actual.count > 0 else {
-            return
-        }
-        let result = try actual.toJSON()
+        let result = try actual.toJSON(options)
         object[key] = result
     }
 
     // [Enum]
     public func encode<Enum: RawRepresentable>(value: [Enum], key: String) throws {
-        guard value.count > 0 else {
-            return
-        }
         let result = try value.flatMap {
-            try ($0.rawValue as? JSONCompatible)?.toJSON()
+            try ($0.rawValue as? JSONCompatible)?.toJSON(options)
         }
         object[key] = result
     }
 
     // [Enum]?
     public func encode<Enum: RawRepresentable>(value: [Enum]?, key: String) throws {
         guard let actual = value else {
-            return
-        }
-        guard actual.count > 0 else {
+            if options.contains(.EncodeNulls) { object[key] = NSNull() }
             return
         }
         let result = try actual.flatMap {
-            try ($0.rawValue as? JSONCompatible)?.toJSON()
+            try ($0.rawValue as? JSONCompatible)?.toJSON(options)
         }
         object[key] = result
     }
 
     // [String:JSONEncodable]
     public func encode<Encodable: JSONEncodable>(dictionary: [String:Encodable], key: String) throws {
-        guard dictionary.count > 0 else {
-            return
-        }
-        let result = try dictionary.toJSON()
+        let result = try dictionary.toJSON(options)
         object[key] = result
     }
     public func encode(dictionary: [String:JSONEncodable], key: String) throws {
-        guard dictionary.count > 0 else {
-            return
-        }
-        let result = try dictionary.toJSON()
+        let result = try dictionary.toJSON(options)
         object[key] = result
     }
-    private func encode(dictionary: JSONDictionary, key: String) throws {
-        guard dictionary.count > 0 && dictionary.valuesAreJSONEncodable() else {
+    func encode(dictionary: JSONDictionary, key: String) throws {
+        guard dictionary.valuesAreJSONEncodable() else {
             return
         }
         let encodable = dictionary.valuesMadeJSONEncodable()
-        let result = try encodable.toJSON()
+        let result = try encodable.toJSON(options)
         object[key] = result
     }
 
     // [String:JSONEncodable]?
     public func encode<Encodable: JSONEncodable>(value: [String:Encodable]?, key: String) throws {
         guard let actual = value else {
+            if options.contains(.EncodeNulls) { object[key] = NSNull() }
             return
         }
-        guard actual.count > 0 else {
-            return
-        }
-        let result = try actual.toJSON()
+        let result = try actual.toJSON(options)
         object[key] = result
     }
 
@@ -292,6 +278,7 @@ public class JSONEncoder {
     // JSONTransformable?
     public func encode<EncodedType, DecodedType>(value: DecodedType?, key: String, transformer: JSONTransformer<EncodedType, DecodedType>) throws {
         guard let actual = value else {
+            if options.contains(.EncodeNulls) { object[key] = NSNull() }
             return
         }
         guard let result = transformer.encoding(actual) else {

JSONCodable/JSONString.swift

@@ -16,7 +16,7 @@ public extension JSONEncodable {
         case is Bool, is Int, is Float, is Double:
             return String(self)
         default:
-            let json = try toJSON()
+            let json = try toJSON([])
             let data = try NSJSONSerialization.dataWithJSONObject(json, options: NSJSONWritingOptions(rawValue: 0))
             guard let string = NSString(data: data, encoding: NSUTF8StringEncoding) else {
                 return ""

JSONCodableTests/EnumTests.swift

@@ -33,7 +33,7 @@ class EnumTests: XCTestCase {
     }
 
     func testEncodingEnum() {
-        guard let json = try? decodedValue.toJSON() else {
+        guard let json = try? decodedValue.toJSON([]) else {
             XCTFail()
             return
         }
@@ -45,7 +45,7 @@ class EnumTests: XCTestCase {
 
         XCTAssertEqual(castedJSON, encodedValue)
 
-        guard let json2 = try? decodedValue2.toJSON() else {
+        guard let json2 = try? decodedValue2.toJSON([]) else {
             XCTFail()
             return
         }