Odtnhj

I'm new in iOS development, so sorry for stupid question in advance.
I have json like this:

 "type":"post",
 "comments":
 "count":0,
 "can_post":1
 ,
 "likes":
 "count":0,
 "user_likes":0,
 "can_like":1,
 "can_publish":1
 ,
 "reposts":
 "count":0,
 "user_reposted":0
 

I want to convert this to class which will contain just likesCount, commentsCount, repostsCount but without creating separate classes for comments, likes, reposts. I'm using Decodable for this and here is my code which doesn't work :)

Code:

final class FeedItem: Decodable 
 enum Keys: String, CodingKey 
 case type,
 likes = "likes.count",
 comments = "comments.count",
 reposts = "reposts.count"
 

 let type: String
 var likes = 0
 var comments = 0
 var reposts = 0

 required convenience init(from decoder: Decoder) throws 
 let container = try decoder.container(keyedBy: Keys.self)
 let type = try container.decode(String.self, forKey: .type)
 let likes = try container.decode(Int.self, forKey: .likes)
 let comments = try container.decode(Int.self, forKey: .comments)
 let reposts = try container.decode(Int.self, forKey: .reposts)
 self.init(type: type, likes: likes, comments: comments, reposts: reposts)
 

 init(type: String,
 likes: Int,
 comments: Int,
 reposts: Int) 
 self.type = type
 self.likes = likes
 self.comments = comments
 self.reposts = reposts
 

Error:

"No value associated with key Keys(stringValue: "likes.count", intValue: nil) ("likes.count")."

The error is very clear, there are no values for associate keys likes.count as the key not exists.

Use

let container = try decoder.container(keyedBy: CodingKeys.self)

and try container.decodeIfPresent(:_) to check for key exists or if not assign empty value.

Code:

struct FeedItem: Codable 

 let type: String
 let commentsCount: Int
 let canPostComment: Int
 let likesCount: Int
 let userLikes: Int
 let canLike: Int
 let canPublish: Int
 let repostsCount: Int
 let userReposted: Int

 enum CodingKeys: String, CodingKey 
 case type = "type"
 case comments = "comments"
 case likes = "likes"
 case reposts = "reposts"
 case count = "count"
 case canPost = "can_post"
 case userLikes = "user_likes"
 case canLike = "can_like"
 case canPublish = "can_publish"
 case userReposted = "user_reposted"
 

 init(from decoder: Decoder) throws 

 let container = try decoder.container(keyedBy: CodingKeys.self)
 self.type = try container.decodeIfPresent(String.self, forKey: .type) ?? ""

 let comments = try container.nestedContainer(keyedBy: CodingKeys.self, forKey: .comments)
 self.commentsCount = try comments.decodeIfPresent(Int.self, forKey: .count) ?? 0
 self.canPostComment = try comments.decodeIfPresent(Int.self, forKey: .canPost) ?? 0

 let likes = try container.nestedContainer(keyedBy: CodingKeys.self, forKey: .likes)
 self.likesCount = try likes.decodeIfPresent(Int.self, forKey: .count) ?? 0
 self.userLikes = try likes.decodeIfPresent(Int.self, forKey: .userLikes) ?? 0
 self.canLike = try likes.decodeIfPresent(Int.self, forKey: .canLike) ?? 0
 self.canPublish = try likes.decodeIfPresent(Int.self, forKey: .canPublish) ?? 0

 let reposts = try container.nestedContainer(keyedBy: CodingKeys.self, forKey: .reposts)
 self.repostsCount = try reposts.decodeIfPresent(Int.self, forKey: .count) ?? 0
 self.userReposted = try reposts.decodeIfPresent(Int.self, forKey: .userReposted) ?? 0
 

 func encode(to encoder: Encoder) throws 

 var container = encoder.container(keyedBy: CodingKeys.self)
 try container.encode(type, forKey: .type)

 var comments = container.nestedContainer(keyedBy: CodingKeys.self, forKey: .comments)
 try comments.encode(commentsCount, forKey: .count)
 try comments.encode(canPostComment, forKey: .canPost)

 var likes = container.nestedContainer(keyedBy: CodingKeys.self, forKey: .likes)
 try likes.encode(likesCount, forKey: .count)
 try likes.encode(userLikes, forKey: .userLikes)
 try likes.encode(canLike, forKey: .canLike)
 try likes.encode(canPublish, forKey: .canPublish)

 var reposts = container.nestedContainer(keyedBy: CodingKeys.self, forKey: .reposts)
 try reposts.encode(repostsCount, forKey: .count)
 try reposts.encode(userReposted, forKey: .userReposted)
 

Data Reading:

let data = //Your JSON data from API
let jsonData = try JSONDecoder().decode(FeedItem.self, from: data)
print("(jsonData.type) (jsonData.canLike)")