First-Post-Model

FirstPostModel.swift

class Post: Mappable {
    var postId: String?
    var title: String?
    var content: String?
    var author: String?
    
    func mapping(map: Map) {
        postId <- map["postId"]
        title <- map["title"]
        content <- map["content"]
        author <- map["author"]
    }
    required init?(map: Map) { }
}

func getPost(postId: String, completion:@escaping ((Post?) -> Void)) {
    let postRef = Database.database()
        .reference().child("posts").child("postId")
    postRef.observeSingleEvent(of: .value, with: { (snapshot) in
        guard !(snapshot.value is NSNull),
            var postDict = snapshot.value as? [String: Any]
            else { return }
        postDict["postId"] = snapshot.key
        completion(Post(JSON: postDict))
    })
}