Get header when enumerate an array - swift

Question

i try to get header informations about remote files which url are located in an array.
My function to get header works perfectly when called alone but doesn't when inside array enumerate.
Here my functions:
func getHeaderInformations (myUrl: URL, completion: #escaping (_ content: String?) -> ()) {
var request = URLRequest(url: myUrl)
request.httpMethod = "HEAD"
let task = URLSession.shared.dataTask(with: request) { (data, response, error) in
guard error == nil, let reponse = response as? HTTPURLResponse, let contentType = reponse.allHeaderFields["Content-Type"],let contentLength = reponse.allHeaderFields["Content-Length"]
else{
completion(nil)
return
}
let content = String(describing: contentType) + "/" + String(describing: contentLength)
completion(content)
}
task.resume()
}
// download picture
func downloadPic (){
let minimumSize=UserDefaults.standard.object(forKey: "Minimum_size") as! Int64
var imgExtension:String=""
var type:String=""
var size:Int64=0
for (_,item) in LiensImgArrayURL.enumerated() {
getHeaderInformations(myUrl: item, completion: { content in
let myInfoArray = content?.components(separatedBy: "/")
type=(myInfoArray?[0])!
imgExtension=(myInfoArray?[1])!
size=Int64((myInfoArray?[2])!)!
})
if (type=="image" && size>=minimumSize) {
SaveFileToDirectory(myRemoteUrl: item, myExtension: imgExtension)
}
}
}
How can i write well this code for "getHeaderInformations" works and return good values inside the func "downLoadPic"?
Thanks for your answers...

Answer 1

Since getHeaderInformations works asynchronously put the code to save the file in the closure.
If you don't need the index in the for loop you don't need enumerated() either.
I tweaked the code bit to get rid of ugly question and exclamation marks and parentheses.
for item in LiensImgArrayURL {
getHeaderInformations(myUrl: item, completion: { content in
if let myInfoArray = content?.components(separatedBy: "/") {
type = myInfoArray[0]
imgExtension = myInfoArray[1]
size = Int64(myInfoArray[2])!
if type == "image" && size >= minimumSize {
SaveFileToDirectory(myRemoteUrl: item, myExtension: imgExtension)
}
}
})
}