I have problems with JSON - Data is repeated - ios

Question

I have a app and problem is repeating the data inside tableView.
How do I fix data replication inside Array ?
func jsonGet(page: Int) {
let pathFull = "https://test.com"
guard let url = URL(string: pathFull) else {return} //
URLSession.shared.dataTask(with: url) { (data, response, err) in
guard let data = data else {return}
do {
let posts = try JSONDecoder().decode(JobsData.self, from: data)
for post in posts.jobs.data {
self.newsPost.append(post)
}
DispatchQueue.main.async {
self.tableView.reloadData()
}
} catch let jsonErr {
self.alertViewBaisc(title: "erorr", text: "error", button: "ok")
print("Error serializing json", jsonErr)
}
}.resume()
}

Answer 1

Issue is you are keep inserting in newsPost data see self.newsPost.append(post) Line
Replace your code with
func jsonGet(page: Int) {
let pathFull = "https://test.com"
guard let url = URL(string: pathFull) else {return} //
URLSession.shared.dataTask(with: url) { (data, response, err) in
guard let data = data else {return}
do {
let posts = try JSONDecoder().decode(JobsData.self, from: data)
var tempPost = [DataType]()
for post in posts.jobs.data {
tempPost.append(post)
}
self. newsPost = tempPost
DispatchQueue.main.async {
self.tableView.reloadData()
}
} catch let jsonErr {
self.alertViewBaisc(title: "erorr", text: "error", button: "ok")
print("Error serializing json", jsonErr)
}
}.resume()
}
Also another way is you can check that if post is already in your array or not
(self. newsPost.filter{$0.uniqueKey == post.uniqueKey}.count == 0)

Answer 2

You can clear the arr with every call
self.newsPost.removeAll()
or declare it like
var newsPost = Set<Post>() // this will guarantee uniqueness in a single fetch
also you don't need a for - loop you can directly do
newsPost = posts.jobs.data
apart from the issue

Answer 3

You can use contains to sort out this issue:
let posts = try JSONDecoder().decode(JobsData.self, from: data)
for post in posts.jobs.data {
if self.newPost contains(post){
//Skip
}
else{
self.newsPost.append(post)
}
}

Answer 4

Just replace
for post in posts.jobs.data {
self.newsPost.append(post)
}
with
self.newsPosts = posts.jobs.data
This avoids the redundant repeat loop as well as the duplicate entries since the new data replaces the old.