Codableの練習。

codable.swift

import UIKit
import Foundation

var str = "Hello, playground"

struct Author: Codable {
    var id: Int?
    var name: String
    var nickname: String?
}

struct Content: Codable {
    var id: Int?
    var title: String
    var author: Author
    var category: Category?
}

struct ContentsResponse: Codable {
    var contents: [Content]
    var isLastPage: Bool
}

struct Category: Codable {
    var id: Int?
    var name: String
}


let data = """
{
    "contents": [
        {
            "id": 1,
            "title": "title",
            "author": {
                "id": 1,
                "name": "山田",
                "nickname": "ドカベン"
            },
        },
        {
            "id": 2,
            "title": "title-2",
            "author": {
                "id": 1,
                "name": "山田",
                "nickname": "ドカベン"
            },
            "category" : {
                "id": 1,
                "name": "カテゴリー"
            }
        },
    ],
    "is_last_page": false
}
""".data(using: .utf8)!

let jsonDecoder = JSONDecoder()
jsonDecoder.keyDecodingStrategy = .convertFromSnakeCase

do {
    let contentsResponse = try jsonDecoder.decode(ContentsResponse.self, from: data)
    contentsResponse.contents[1].category!.name
    contentsResponse.isLastPage
} catch {
    print(error.localizedDescription)
}