HandyJSON is a framework written in Swift which to make converting model objects( pure classes/structs ) to and from JSON easy on iOS.
Compared with others, the most significant feature of HandyJSON is that it does not require the objects inherit from NSObject(not using KVC but reflection), neither implements a 'mapping' function(write value to memory to achieve property assignment).
HandyJSON is totally depend on the memory layout rules infered from Swift runtime code. We are watching it and will follow every bit if it change.
class BasicTypes: HandyJSON {
var int: Int = 2
var doubleOptional: Double?
var stringImplicitlyUnwrapped: String!
required init() {}
}
let jsonString = "{\"doubleOptional\":1.1,\"stringImplicitlyUnwrapped\":\"hello\",\"int\":1}"
if let object = BasicTypes.deserialize(from: jsonString) {
print(object.int)
print(object.doubleOptional!)
print(object.stringImplicitlyUnwrapped)
}
let object = BasicTypes()
object.int = 1
object.doubleOptional = 1.1
object.stringImplicitlyUnwrapped = “hello"
print(object.toJSON()!) // serialize to dictionary
print(object.toJSONString()!) // serialize to JSON string
print(object.toJSONString(prettyPrint: true)!) // serialize to pretty JSON string
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Serialize/Deserialize Object/JSON to/From JSON/Object
-
Naturally use object property name for mapping, no need to specify a mapping relationship
-
Support almost all types in Swift, including enum
-
Support struct
-
Custom transformations for mapping
-
Type-Adaption, such as string json field maps to int property, int json field maps to string property
An overview of types supported can be found at file: BasicTypes.swift
-
iOS 8.0+/OSX 10.9+/watchOS 2.0+/tvOS 9.0+
-
Swift 2.3+ / Swift 3.0+
To use with Swift 2.x using == 0.4.0
To use with Swift 3.x using >= 1.7.2
For Legacy Swift support, take a look at the swift2 branch.
Add the following line to your Podfile
:
pod 'HandyJSON', '~> 1.7.2'
Then, run the following command:
$ pod install
You can add a dependency on HandyJSON
by adding the following line to your Cartfile
:
github "alibaba/HandyJSON" ~> 1.7.2
You can integrate HandyJSON
into your project manually by doing the following steps:
- Open up
Terminal
,cd
into your top-level project directory, and addHandyJSON
as a submodule:
git init && git submodule add https://github.com/alibaba/HandyJSON.git
-
Open the new
HandyJSON
folder, drag theHandyJSON.xcodeproj
into theProject Navigator
of your project. -
Select your application project in the
Project Navigator
, open theGeneral
panel in the right window. -
Click on the
+
button under theEmbedded Binaries
section. -
You will see two different
HandyJSON.xcodeproj
folders each with four different versions of the HandyJSON.framework nested inside a Products folder.
It does not matter which Products folder you choose from, but it does matter which HandyJSON.framework you choose.
-
Select one of the four
HandyJSON.framework
which matches the platform your Application should run on. -
Congratulations!
To support deserialization from JSON, a class/struct need to conform to 'HandyJSON' protocol. It's truly protocol, not some class inherited from NSObject.
To conform to 'HandyJSON', a class need to implement an empty initializer.
class BasicTypes: HandyJSON {
var int: Int = 2
var doubleOptional: Double?
var stringImplicitlyUnwrapped: String!
required init() {}
}
let jsonString = "{\"doubleOptional\":1.1,\"stringImplicitlyUnwrapped\":\"hello\",\"int\":1}"
if let object = BasicTypes.deserialize(from: jsonString) {
// …
}
For struct, since the compiler provide a default empty initializer, we use it for free.
struct BasicTypes: HandyJSON {
var int: Int = 2
var doubleOptional: Double?
var stringImplicitlyUnwrapped: String!
}
let jsonString = "{\"doubleOptional\":1.1,\"stringImplicitlyUnwrapped\":\"hello\",\"int\":1}"
if let object = BasicTypes.deserialize(from: jsonString) {
// …
}
But also notice that, if you have a designated initializer to override the default one in the struct, you should explicitly declare an empty one(no required
modifier need).
To be convertable, An enum
must conform to HandyJSONEnum
protocol. Nothing special need to do now.
enum AnimalType: String, HandyJSONEnum {
case Cat = "cat"
case Dog = "dog"
case Bird = "bird"
}
struct Animal: HandyJSON {
var name: String?
var type: AnimalType?
}
let jsonString = "{\"type\":\"cat\",\"name\":\"Tom\"}"
if let animal = Animal.deserialize(from: jsonString) {
print(animal.type?.rawValue)
}
'HandyJSON' support classes/structs composed of optional
, implicitlyUnwrappedOptional
, array
, dictionary
, objective-c base type
, nested type
etc. properties.
class BasicTypes: HandyJSON {
var bool: Bool = true
var intOptional: Int?
var doubleImplicitlyUnwrapped: Double!
var anyObjectOptional: Any?
var arrayInt: Array<Int> = []
var arrayStringOptional: Array<String>?
var setInt: Set<Int>?
var dictAnyObject: Dictionary<String, Any> = [:]
var nsNumber = 2
var nsString: NSString?
required init() {}
}
let object = BasicTypes()
object.intOptional = 1
object.doubleImplicitlyUnwrapped = 1.1
object.anyObjectOptional = "StringValue"
object.arrayInt = [1, 2]
object.arrayStringOptional = ["a", "b"]
object.setInt = [1, 2]
object.dictAnyObject = ["key1": 1, "key2": "stringValue"]
object.nsNumber = 2
object.nsString = "nsStringValue"
let jsonString = object.toJSONString()!
if let object = BasicTypes.deserialize(from: jsonString) {
// ...
}
HandyJSON
supports deserialization from designated path of JSON.
class Cat: HandyJSON {
var id: Int64!
var name: String!
required init() {}
}
let jsonString = "{\"code\":200,\"msg\":\"success\",\"data\":{\"cat\":{\"id\":12345,\"name\":\"Kitty\"}}}"
if let cat = Cat.deserialize(from: jsonString, designatedPath: "data.cat") {
print(cat.name)
}
Notice that all the properties of a class/struct need to deserialized should be type conformed to HandyJSON
.
class Component: HandyJSON {
var aInt: Int?
var aString: String?
required init() {}
}
class Composition: HandyJSON {
var aInt: Int?
var comp1: Component?
var comp2: Component?
required init() {}
}
let jsonString = "{\"num\":12345,\"comp1\":{\"aInt\":1,\"aString\":\"aaaaa\"},\"comp2\":{\"aInt\":2,\"aString\":\"bbbbb\"}}"
if let composition = Composition.deserialize(from: jsonString) {
print(composition)
}
A subclass need deserialization, it's superclass need to conform to HandyJSON
.
class Animal: HandyJSON {
var id: Int?
var color: String?
required init() {}
}
class Cat: Animal {
var name: String?
required init() {}
}
let jsonString = "{\"id\":12345,\"color\":\"black\",\"name\":\"cat\"}"
if let cat = Cat.deserialize(from: jsonString) {
print(cat)
}
If the first level of a JSON text is an array, we turn it to objects array.
class Cat: HandyJSON {
var name: String?
var id: String?
required init() {}
}
let jsonArrayString: String? = "[{\"name\":\"Bob\",\"id\":\"1\"}, {\"name\":\"Lily\",\"id\":\"2\"}, {\"name\":\"Lucy\",\"id\":\"3\"}]"
if let cats = [Cat].deserialize(from: jsonArrayString) {
cats.forEach({ (cat) in
// ...
})
}
HandyJSON
let you customize the key mapping to JSON fields, or parsing method of any property. All you need to do is implementing an optional mapping
function, do things in it.
We bring the transformer from ObjectMapper
. If you are familiar with it, it’s almost the same here.
class Cat: HandyJSON {
var id: Int64!
var name: String!
var parent: (String, String)?
required init() {}
func mapping(mapper: HelpingMapper) {
// specify 'cat_id' field in json map to 'id' property in object
mapper <<<
self.id <-- "cat_id"
// specify 'parent' field in json parse as following to 'parent' property in object
mapper <<<
self.parent <-- TransformOf<(String, String), String>(fromJSON: { (rawString) -> (String, String)? in
if let parentNames = rawString?.characters.split(separator: "/").map(String.init) {
return (parentNames[0], parentNames[1])
}
return nil
}, toJSON: { (tuple) -> String? in
if let _tuple = tuple {
return "\(_tuple.0)/\(_tuple.1)"
}
return nil
})
}
}
let jsonString = "{\"cat_id\":12345,\"name\":\"Kitty\",\"parent\":\"Tom/Lily\"}"
if let cat = Cat.deserialize(from: jsonString) {
print(cat.id)
print(cat.parent)
}
If any non-basic property of a class/struct could not conform to HandyJSON
/HandyJSONEnum
or you just do not want to do the deserialization with it, you should exclude it in the mapping function.
class NotHandyJSONType {
var dummy: String?
}
class Cat: HandyJSON {
var id: Int64!
var name: String!
var notHandyJSONTypeProperty: NotHandyJSONType?
var basicTypeButNotWantedProperty: String?
required init() {}
func mapping(mapper: HelpingMapper) {
mapper >>> self.notHandyJSONTypeProperty
mapper >>> self.basicTypeButNotWantedProperty
}
}
let jsonString = "{\"name\":\"cat\",\"id\":\"12345\"}"
if let cat = Cat.deserialize(from: jsonString) {
print(cat)
}
-
Int
/Bool
/Double
/Float
/String
/NSNumber
/NSString
-
RawRepresentable
enum -
NSArray/NSDictionary
-
Int8/Int16/Int32/Int64
/UInt8/UInt16/UInt23/UInt64
-
Optional<T>/ImplicitUnwrappedOptional<T>
// T is one of the above types -
Array<T>
// T is one of the above types -
Dictionary<String, T>
// T is one of the above types -
Nested of aboves
Now, a class/model which need to serialize to JSON should also conform to HandyJSON
protocol.
class BasicTypes: HandyJSON {
var int: Int = 2
var doubleOptional: Double?
var stringImplicitlyUnwrapped: String!
required init() {}
}
let object = BasicTypes()
object.int = 1
object.doubleOptional = 1.1
object.stringImplicitlyUnwrapped = “hello"
print(object.toJSON()!) // serialize to dictionary
print(object.toJSONString()!) // serialize to JSON string
print(object.toJSONString(prettyPrint: true)!) // serialize to pretty JSON string
It’s all like what we do on deserialization. A property which is excluded, it will not take part in neither deserialization nor serialization. And the mapper items define both the deserializing rules and serializing rules. Refer to the usage above.
HandyJSON is released under the Apache License, Version 2.0. See LICENSE for details.