Why I sometime get 'The connection was lost' error? - ios

Question

so, I am making an app and want to GET data from my own server using alamofire. but I don't know why, I SOMETIME get the error
HTTP load failed (error code: -1005 [1:57]) .
finished with error -
code: -1005. error: The network connection was lost.
and this only happen when I try to get data to my own server. I try to compare to get data from other server, from darksky API, and I never get the error. here is the code I use to get data from my own server and to darksky API.
the error usually occurred when .....
after I start the app, and I push the home button ( so the app enter the background state), and when I back to the app, and at this time, I usually get the error.
so maybe I got the error when prepareDataBeforeEnterForeground is triggered. not always happened, and I don't know why it happened only to my server, and I need to know how to fix this.
does the error comes from my code or from the server?
import UIKit
import Alamofire
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
getData()
getPrepareDataBeforeEnterForeground() // using notification center
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
getData()
}
func getData() {
// to make request to my own server OR to DarkSky API
let url = URL(string: "https://")
let parameters : [String:String] = ["xxx": "xxxx"]
Alamofire.request(url!, method: .get, parameters: parameters).responseJSON { (response) in
switch response.result {
case .failure(let error):
print("Error: \(error.localizedDescription)")
case .success(let value) :
// parse the data
}
}
}
func getPrepareDataBeforeEnterForeground() {
// to trigger some function after the enter the background state
NotificationCenter.default.addObserver(self, selector: #selector(ViewController.prepareDataBeforeEnterForeground), name: NSNotification.Name.UIApplicationWillEnterForeground, object: nil)
}
#objc func prepareDataBeforeEnterForeground() {
getData()
}
}

Answer 1

For reference, your error code correlates to:
kCFURLErrorNetworkConnectionLost = -1005
From my own personal experience, I get this error when the parameters I'm trying to send to the server are incorrect or malformed.
In your case, I can't seem to see where you are accepting parameters or defining it, so that might be your issue.
If its coming from your server, you will have to check the error logs for the server software (Apache, nginx, etc) (if you have them).
Here is an example of a valid request:
let parameters: Parameters = [
"foo": "bar",
"baz": ["a", 1],
"qux": [
"x": 1,
"y": 2,
"z": 3
]
]
Alamofire.request("https://httpbin.org/post", method: .post, parameters: parameters)
To add on, it doesn't appear that you are sending any headers either, so you could be causing your server to reject the request completely.