Cancel all web service calls from Alamofire

Question

In my project there are 4 web services running in the background. I would like to stop all these services on logout from the current state without waiting for response. I have found this code for doing that

Alamofire.Manager.sharedInstance.session.invalidateAndCancel()

But after calling this, I am not able to make service calls again. Is there any way I can cancel all the running requests?

Here's my service calling code

func getAllCount(parameters: [String: AnyObject],completion: (success : Bool) -> Void) {

            PKHUD.sharedHUD.contentView = PKHUDTextView(text: "Loading...")
            PKHUD.sharedHUD.show()
            request = Alamofire.request(.POST, GlobalConstants.KGetAllCount, parameters: parameters, encoding:.JSON).responseJSON
                {
                    response in switch response.result {
                    case .Success(let JSON):
                        PKHUD.sharedHUD.hide()
                        print("Success with JSON: \(JSON)")
                        let status : NSString = JSON.valueForKey("status") as! String
                        if(status .isEqualToString("1")){
                            MyViewState.QJoined = JSON.valueForKeyPath("data.TotalJoinQueue") as! String
                            MyViewState.Qstarted = JSON.valueForKeyPath("data.TotalCreatedQueue") as! String
                            MyViewState.Bumps = JSON.valueForKeyPath("data.TotalBump") as! String
                            completion(success: true)

                            break
                        }else{
                            completion(success: false)
                            Helper.globalAlert(JSON.valueForKey("data") as! String)
                            break
                        }
                    case .Failure(let error):
                        PKHUD.sharedHUD.hide()
                        print("Request failed with error: \(error)")
                        completion(success: false)
                        break

                    }
            }
        }

you can cancel only pending request. if the request is executing, it is to late ... you are not running web services at all. — user3441734, Jan 03 '16 at 12:48
Kindly review this answer http://stackoverflow.com/a/27022598/1030951 — HarshIT, Jan 06 '16 at 12:58

Alex Pelletier · Accepted Answer · 2016-01-05T06:06:31.643

9

As far as I can tell there is no obvious/easy way to recreate the session. The suggested way to handle this problem is to keep and array of requests static var requests = [Alamofire.Request?]() then when you want to stop all the requests you can call use request.cancel(). Using this approach you will have to append each request after creating it.

class func stopAllRequests(){
    for request in MyClass.requests{
        if let request = request{
            request.cancel()
        }
    }
}

Similar Issue

edited Jan 05 '16 at 06:06

answered Jan 03 '16 at 11:32

Alex Pelletier

4,933
6
34
58

This is for me the best way to handle this (and the one I use in my app) – Jan 04 '16 at 16:28
This will cancel request for one class only. – Janak Thakkar Jan 05 '16 at 05:56
@JanakThakkar the idea here is just to store all of your requests in an array. This array could be shared between classes or helps in a managing class. – Alex Pelletier Apr 06 '17 at 22:26

score 9 · Answer 2 · answered Jan 06 '16 at 03:03

NSURLSession does have these methods which returns you all the requests that have not completed yet. You can get those, loop through them and cancel each one -- similar to what people have suggested above.

    if #available(iOS 9.0, *) {
        Manager.sharedInstance.session.getAllTasksWithCompletionHandler { (tasks) -> Void in
            tasks.forEach({ $0.cancel() })
        }
    } else {
        // Fallback on earlier versions
        Manager.sharedInstance.session.getTasksWithCompletionHandler({
            $0.0.forEach({ $0.cancel() })
            $0.1.forEach({ $0.cancel() })
            $0.2.forEach({ $0.cancel() })
        })
    }

score 2 · Answer 3 · answered Jan 05 '16 at 05:57

2

class func emptyArr() {
        for(var i=0; i<arrReq.count; i++){
            request = arrReq.objectAtIndex(i) as? Alamofire.Request
            request?.cancel()
        }
    }

answered Jan 05 '16 at 05:57

Janak Thakkar

414
5
20

Cancel all web service calls from Alamofire

3 Answers3