JSONPatch

A Swift μ-framework for creating RFC6902 compliant JSON patch objects

Requirements

• iOS 8.0+ / macOS 10.13+
• Swift 4.2+

IMPORTANT!

The framework relies on the Objective C runtime for converting keypaths into strings, and so it is crucial that the properties the keypaths point to are representable in Objective C. To achieve this, you will have to add the @objc annotation at each variable declaration.

class Patch: NSObject {
    @objc var baz: String!
    @objc var foo: String!
    @objc var hello: [String]!
}

Alternatively you can also use the @objcMembers annotation at the class level if all class members are representible in Objective C

@objcMembers class Patch: NSObject {
    ...
}

Installation

Carthage

To integrate JSONPatch into your Xcode project using Carthage, specify it in your Cartfile:

github "peterringset/JSONPatch" ~> 2.0

CocoaPods

To integrate JSONPatch into your Xcode project using CocoaPods, specify it in your Podfile:

source 'https://github.com/CocoaPods/Specs.git'
platform :ios, '8.0'
use_frameworks!

target '<Your Target Name>' do
    pod 'PRJSONPatch', '~> 2.0'
end

Swift package manger

To add a package dependency to your Xcode project, select File > Swift Packages > Add Package Dependency and enter https://github.com/peterringset/JSONPatch.

Usage

Create JSON patch objects using keypath’s in Swift:

import JSONPatch

let stringChanges: [JSONPatch<Patch>] = [
    .replace(\.baz, value: "boo"),
    .remove(\.foo)
]
let arrayChanges: [JSONPatch<Patch>] = [
    .add(\.hello, value: ["world"])
]

Then, once you’ve created a collection of changes you can use JSONEncoder to convert it to json data:

let encoder = JSONEncoder()
encoder.outputFormatting = .prettyPrinted

let data = try! encoder.encode(changes)
print(String(data: data, encoding: .utf8)!)

This will print the following json:

[
  {
    "op" : "replace",
    "path" : "\/baz",
    "value" : "boo"
  },
  {
    "op" : "remove",
    "path" : "\/foo"
  },
  {
    "op" : "add",
    "path" : "\/hello",
    "value" : [
      "world"
    ]
  }
]

JSONPatch supports all the verbs specified in RFC6902, add, remove, replace, move, copy and test.