GuardedSwiftyJSON

Why should I use this?

This library makes initializing models with JSON data with SwiftyJSON a lot easier.

Often with SwiftyJSON I end up doing something like this:

import SwiftyJSON

struct Model {
  let name : String
  let height : Double

  init?(json: JSON) {
    guard let name = json["name"].string, let height = json["height"].double else {
      return nil
    }

    self.name = name
    self.height = height
  }
}

which gets annoying when you have more than two or three properties you want to guard your model on.

Example

GuardedSwiftyJSON solves this by providing an initializer which will fail the initialization if properties that you request are not present.

import GuardedSwiftyJSON

struct Model : JsonInitializable {
  let name : String
  let height : Double

  init(json: GuardedJSON) {
    name = json["name"].string
    height = json["height"].double
  }
}

And then your object will get an initializer that allows it to be created from a Swifty JSON object:

let data : JSON = ["name": "Arthur Swiftington", "height": 182.8]

let model : Model? = Model(json: data)

If either one of name or height are not present, the initialization will fail.

You can specify optional properties by using the optional prefix:

import GuardedSwiftyJSON

struct Model : JsonInitializable {
  let name : String
  let height : Double?

  init(json: GuardedJSON) {
    name = json["name"].string
    height = json["height"].optionalDouble
  }
}

Then, if those optional properties do not exist, they will not cause initialization to abort.

GuardedSwiftyJSON provies the following protocol

protocol JsonInitializable {
  init?(json: JSON)
  init(json: GuardedJSON)
}

and a default implementation of init?(json: JSON) which automatically calls the proxying initializer and then fails the initialization if any of the required JSON properties are not present.

Installation

Carthage

github "wiggzz/GuardedSwiftyJSON"

Cocoapods

pod 'GuardedSwiftyJSON'

Contributing

Pull requests and issues are welcomed.