How can I get data out of NSURLRequest config object - ios

I have an Angular web build inside an iOS app and want to POST requests up to the native layer with some JSON that I can use to build some native functionality. I am using the old UIWebView (because Angular) so am using an NSURLProtocol to intercept the request. This works and I can break at the point that the request comes in. The problem is that I can not see the JSON in the data property at this point because it is not the response. The request is still in the config object but I have no idea how to grab this.
My angular code for creating the post is currently like this:
var newdata = $.param({
json: JSON.stringify({
name: "Lee"
})
});
$http.post(url, newdata)
and in my NSURLProtocol class I am successfully intercepting this POST in this method but the HTTPBody property is nil:
override class func canInitWithRequest(request:NSURLRequest) -> Bool {
if (request.URL!.absoluteString as NSString).containsString("request_media_gallery") {
if(request.HTTPBody != nil){
let data:NSData = request.HTTPBody!
print(data)
}
return true
}
return request.URL?.host == "file"
}
If I debug this in chrome I get a 405 because of CORS but I can see that my request object does not have any data but does have a config object. Here's the console log from Chrome:


By the time a URL request gets down to the protocol layer, IIRC, the URL Loading System sanitizes it in a lot of ways. In particular, if a request has an HTTPBody object associated with it, it basically does this:
req.HTTPBodyStream = [NSInputStream inputStreamWithData:req.HTTPBody];
req.HTTPBody = nil;
As a result, to get the data, you need to read from the HTTPBodyStream, regardless of whether the request was originally created with an NSData object or a body stream.

Related

HTTP DELETE Works From Browser But Not From Postman or IOS App

When attempting an http request to my rest api, I continually get a 401 error when using the following code. I don not get this error making any other type of request. I have provided the function that makes the request below.
func deleteEvent(id: Int){
eventUrl.append(String(id))
let request = NSMutableURLRequest(url: NSURL(string: eventUrl)! as URL)
request.httpMethod = "DELETE"
print(eventUrl)
eventUrl.removeLast()
print(self.token!)
request.allHTTPHeaderFields = ["Authorization": "Token \(self.token)"]
let task = URLSession.shared.dataTask(with: request as URLRequest) { data, response, error in
if error != nil {
print("error=\(String(describing: error))")
//put variable that triggers error try again view here
return
}
print("response = \(String(describing: response))")
}
task.resume()
}
When sending the delete request with postman, the rest api just returns the data I want to delete but does not delete it. For reference I have posted the view and permissions classes associated with this request Any help understanding why this may be resulting in an error is greatly appreciated!
Views.py
class UserProfileFeedViewSet(viewsets.ModelViewSet):
"""Handles creating, reading and updating profile feed items"""
authentication_classes = (TokenAuthentication,)
serializer_class = serializers.ProfileFeedItemSerializer
queryset = models.ProfileFeedItem.objects.all()
permission_classes = (permissions.UpdateOwnStatus, IsAuthenticated)
def perform_create(self, serializer):
"""Sets the user profile to the logged in user"""
#
serializer.save(user_profile=self.request.user)
Permissions.py
class UpdateOwnStatus(permissions.BasePermission):
"""Allow users to update their own status"""
def has_object_permission(self, request, view, obj):
"""Check the user is trying to update their own status"""
if request.method in permissions.SAFE_METHODS:
return True
return obj.user_profile.id == request.user.id
HEADER SENT WITH DELETE REQUEST VIA POSTMAN

Preface: You leave out too much relevant information from the question for it to be properly answered. Your Swift code looks, and please don't be offended, a bit beginner-ish or as if it had been migrated from Objective-C without much experience.
I don't know why POSTMAN fails, but I see some red flags in the Swift code you might want to look into to figure out why your iOS app fails.
I first noticed that eventUrl seems to be a String property of the type that contains the deleteEvent function. You mutate it by appending the event id, construct a URL from it (weirdly, see below), then mutate it back again. While this in itself is not necessarily wrong, it might open the doors for racing conditions depending how your app works overall.
More importantly: Does your eventUrl end in a "/"? I assume your DELETE endpoint is of the form https://somedomain.com/some/path/<id>, right? Now if eventUrl just contains https://somedomain.com/some/path your code constructs https://somedomain.com/some/path<id>. The last dash is missing, which definitely throws your backend off (how I cannot say, as that depends how the path is resolved in your server app).
It's hard to say what else is going from from the iOS app, but other than this potential pitfall I'd really recommend using proper Swift types where possible. Here's a cleaned up version of your method, hopefully that helps you a bit when debugging:
func deleteEvent(id: Int) {
guard let baseUrl = URL(string: eventUrl), let token = token else {
// add more error handling code here and/or put a breakpoint here to inspect
print("Could not create proper eventUrl or token is nil!")
return
}
let deletionUrl = baseUrl.appendingPathComponent("\(id)")
print("Deletion URL with appended id: \(deletionUrl.absoluteString)")
var request = URLRequest(url: deletionUrl)
request.httpMethod = "DELETE"
print(token) // ensure this is correct
request.allHTTPHeaderFields = ["Authorization": "Token \(token)"]
let task = URLSession.shared.dataTask(with: request) { data, response, error in
if let error = error {
print("Encountered network error: \(error)")
return
}
if let httpResponse = response as? HTTPURLResponse {
// this is basically also debugging code
print("Endpoint responded with status: \(httpResponse.statusCode)")
print(" with headers:\n\(httpResponse.allHeaderFields)")
}
// Debug output of the data:
if let data = data {
let payloadAsSimpleString = String(data: data, encoding: .utf8) ?? "(can't parse payload)"
print("Response contains payload\n\(payloadAsSimpleString)")
}
}
task.resume()
}
This is obviously still limited in terms of error handling, etc., but a little more swifty and contains more console output that will hopefully be helpful.
The last important thing is that you have to ensure iOS does not simply block your request due to Apple Transport Security: Make sure your plist has the expected entries if needed (see also here for a quick intro).

Save and resend Alamofire request

I am using Alamofire and I want to send a get request. If this fails, I want to retry it again after some other operations.
I save the request in a variable:
let myRequest = Alamofire.request("myurl", method: .get)
and in another function:
func retry(request:DataRequest) {
request.responseSwiftyJSON { response in
// ... code to handle the response ...
}
}
In this way, I can call multiple times the retry function, passing the same object myRequest.
However, the request is sent correctly only the first time, then I think it is cached (or in some way the Alamofire object realizes that the response field of the request object is already valid) and the request is not sent again to the server.
To solve this problem, I tried to change a little bit the retry function in this way:
func retry2(request:DataRequest) {
Alamofire.request(request.request!).responseSwiftyJSON { response in
// ... code to handle the response ...
}
}
This should initialize a new Alamofire request using only the URLRequest field of the saved request, but now the request is called twice every time! (I check it in my backend and I am sure this is caused by using this approach).
Is there any way to resend the original saved request? Does Alamofire have some way to initialize a new request from a saved one?
Solution
I ended up by doing something like #JonShier and #DuncanC suggested me:
struct APIRequest {
let url: URLConvertible
let method: HTTPMethod
let parameters: Parameters?
let encoding: ParameterEncoding
let headers: HTTPHeaders?
init(_ url:URLConvertible, method:HTTPMethod = .get, parameters:Parameters? = nil, encoding:ParameterEncoding = URLEncoding.default, headers:HTTPHeaders? = nil) {
self.url = url
self.method = method
self.parameters = parameters
self.encoding = encoding
self.headers = headers
}
func make() -> DataRequest {
return Alamofire.request(url, method: method, parameters: parameters, encoding: encoding, headers: headers)
}
}

I haven't used AlamoFire much, and that minimal use was a couple of years ago.
Looking around in the AlamoFire code, it appears that the request() function returns a DataRequest object. Further, it looks like a DataRequest is a reference type that is meant to track a specific request to a server and it's responses.
It looks to make like once you create one, you use it until it completes or fails, and then discard it. They do not appear to be intended to be reused for subsequent requests of the same type.
To summarize:
Question: "How do I reuse AlamoFire DataRequest objects."
Answer: "Don't do that."

Get Response of XML HTTP url using alamofire and Swift4 IOS

I am developing an application in which I need to get the response code of a HTTP URL, The URL returns an xml which is encrypted. I only need to get that encrypted response code into a variable.
I've used Alamofire for http request.
Thanks in advance!

Alamofire.request("URL Goes here",method:.get)
.response { response in
if let data = response.data {
print(data)
var xml = SWXMLHash.parse(data)
print(xml["e1"]["e2"].element?.text)
}
}

How to set custom HTTP headers to requests made by a WKWebView

I have built an app that includes a WKWebView, and the website that the web view loads supports multiple languages. How can I change the Accept-Language header in a WKWebView, or other HTTP headers for that matter?

I've got it working in a way, but only get requests will have the custom header. As jbelkins answered in the linked so from Gabriel Cartiers comment to your question, you will have to manipulate the request and load it anew.
I've got it working for GET-Requests like this:
(it's in xamarin 0> c#, but i think you will get the idea)
i've created a private field
private bool _headerIsSet
which i check every time a request is made in the deligate method:
[Foundation.Export("webView:decidePolicyForNavigationAction:decisionHandler:")]
public void DecidePolicy(WKWebView webView, WKNavigationAction navigationAction, Action<WKNavigationActionPolicy> decisionHandler)
{
var request = navigationAction.Request;
// check if the header is set and if not, create a muteable copy of the original request
if (!_headerIsSet && request is NSMuteableUrlRequest muteableRequest);
{
// define your custom header name and value
var keys = new object[] {headerKeyString};
var values = new object[] {headerValueString};
var headerDict = NSDictionary.FromObjectsAndKeys(values, keys);
// set the headers of the new request to the created dict
muteableRequest.Headers = headerDict;
_headerIsSet = true;
// attempt to load the newly created request
webView.LoadRequest(muteableRequest);
// abort the old one
decisionHandler(WKNavigationActionPolicy.Cancel);
// exit this whole method
return;
}
else
{
_headerIsSet = false;
decisionHandler(WKNavigationActionPolicy.Allow);
}
}
As i said, this only works for GET-Requests. Somehow, POST-Requests don't contain the body data of the original request (request.Body and request.BodyStream are null), so the muteableRequest (which is a muteable copy of the original request) won't contain the body data of the original request.
I hope this will help you or others that approach the same problem.
Edit: For your needs, set "Accept-Language" as the key

Simply can set needed language ISO 639-1 code in URL request like below, so that we can get user preferred or locale language response from server side.
Swift 4 & above
var request = URLRequest(url: URL(string: "YourUrlStr"))
request.setValue("en", forHTTPHeaderField: "Accept-Language")
wkWebView.load(request)
Objective-C
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:[NSURL URLWithString:YourUrlStr]];
[request setValue:#"en" forHTTPHeaderField:#"Accept-Language"];
[wkWebView loadRequest:urlRequest];

WKWebView supports localization out of the box. You will not be required set the 'Accept-Language' header field.
For some reason if you are required to, this is how it can be done.
Create a 'URLRequest' an instance of URL initialized with the desired website
var request = URLRequest(url: url)
Maintain a mapping of locales required and set the 'Accept-Language' header field accordingly
request.setValue("de-de", forHTTPHeaderField: "Accept-Language")
Load the 'URLRequest' using an instance of 'WKWebView'
webview.load(request)
Similarly any header field can be changed

How can I process multiple links of JSON data?

The code works perfectly. The problem is that, after trying for a while, I cannot figure out how to make my program process a second link of different JSON data.
Here is my viewDidLoad where everything goes on:
override func viewDidLoad() {
super.viewDidLoad()
var err: NSError?
let urlPath: String = "https://na.api.pvp.net/api/lol/na/v1.4/summoner/by-name/" + searchFieldDataPassed + "?api_key=(removed my private api key for obvious reasons"
var url: NSURL = NSURL(string: urlPath)!
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithURL(url) { data, response, error in
// cast response as NSHTTPURLResponse and switch on statusCode if you like
if let httpResponse = response as? NSHTTPURLResponse { switch httpResponse.statusCode { case 200..<300: println("OK") default: println("Not OK") } }
// parse JSON using NSJSONSerialization if you've got data
if let jsonResult = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: &err) as? NSDictionary,
let include = jsonResult.objectForKey(self.searchFieldDataPassed) as? NSDictionary {
if let summLevel = include[ "summonerLevel" ] as? NSNumber {
dispatch_async(dispatch_get_main_queue()) {
self.summonerLevel.text = "\(summLevel.integerValue)"
println("summoner level: \(summLevel.integerValue)")
}
}
if let profIconId = include[ "profileIconId" ] as? NSNumber {
dispatch_async(dispatch_get_main_queue()) {
self.profileIconId.text = "\(profIconId.integerValue)"
println("profile icon id: \(profIconId.integerValue)")
}
}
if let idNum = include [ "id" ] as? NSNumber {
dispatch_async(dispatch_get_main_queue()) {
self.idNumber = idNum
println("id number: \(self.idNumber)")
}
}
}
// spawn off another network call here if you like
}
task.resume()
}
That is from my secondViewController where all the processing goes on for JSON and then is displayed.
Here is the JSON data that I'm processing (for the first JSON parsing):
{"soon2challenger":{"id":43993167,"name":"soon2challenger","profileIconId":844,"summonerLevel":30,"revisionDate":1435549418000}}
All of that works fine, now, I want to process this JSON data which actually takes the id from the first parsed JSON data and uses it in the link to process more data, which I would like to output, part of it, to the screen.
Second JSON data:
{"summonerId":43993167,"playerStatSummaries":[{"playerStatSummaryType":"AramUnranked5x5","wins":25,"modifyDate":1423007927000,"aggregatedStats":{"totalChampionKills":676,"totalTurretsKilled":20,"totalAssists":991}},{"playerStatSummaryType":"CAP5x5","wins":15,"modifyDate":1429065922000,"aggregatedStats":{"totalChampionKills":312,"totalMinionKills":4885,"totalTurretsKilled":31,"totalNeutralMinionsKilled":511,"totalAssists":216}},{"playerStatSummaryType":"CoopVsAI","wins":28,"modifyDate":1421882181000,"aggregatedStats":{"totalChampionKills":266,"totalMinionKills":2802,"totalTurretsKilled":50,"totalNeutralMinionsKilled":385,"totalAssists":164,"maxChampionsKilled":0,"averageNodeCapture":0,"averageNodeNeutralize":0,"averageTeamObjective":0,"averageTotalPlayerScore":49,"averageCombatPlayerScore":0,"averageObjectivePlayerScore":49,"averageNodeCaptureAssist":0,"averageNodeNeutralizeAssist":0,"maxNodeCapture":0,"maxNodeNeutralize":0,"maxTeamObjective":0,"maxTotalPlayerScore":49,"maxCombatPlayerScore":0,"maxObjectivePlayerScore":49,"maxNodeCaptureAssist":0,"maxNodeNeutralizeAssist":0,"totalNodeNeutralize":0,"totalNodeCapture":0,"averageChampionsKilled":0,"averageNumDeaths":0,"averageAssists":0,"maxAssists":0}},{"playerStatSummaryType":"CoopVsAI3x3","wins":15,"modifyDate":1421882181000,"aggregatedStats":{"totalChampionKills":140,"totalMinionKills":1114,"totalTurretsKilled":9,"totalNeutralMinionsKilled":449,"totalAssists":91}},{"playerStatSummaryType":"OdinUnranked","wins":1,"modifyDate":1421882181000,"aggregatedStats":{"totalChampionKills":31,"totalAssists":45,"maxChampionsKilled":10,"averageNodeCapture":4,"averageNodeNeutralize":4,"averageTeamObjective":0,"averageTotalPlayerScore":843,"averageCombatPlayerScore":268,"averageObjectivePlayerScore":575,"averageNodeCaptureAssist":3,"averageNodeNeutralizeAssist":1,"maxNodeCapture":6,"maxNodeNeutralize":7,"maxTeamObjective":2,"maxTotalPlayerScore":1468,"maxCombatPlayerScore":529,"maxObjectivePlayerScore":939,"maxNodeCaptureAssist":5,"maxNodeNeutralizeAssist":2,"totalNodeNeutralize":22,"totalNodeCapture":25,"averageChampionsKilled":5,"averageNumDeaths":5,"averageAssists":8,"maxAssists":19}},{"playerStatSummaryType":"RankedSolo5x5","wins":116,"losses":120,"modifyDate":1433630047000,"aggregatedStats":{"totalChampionKills":1699,"totalMinionKills":33431,"totalTurretsKilled":219,"totalNeutralMinionsKilled":6501,"totalAssists":1969}},{"playerStatSummaryType":"RankedTeam3x3","wins":0,"losses":0,"modifyDate":1377726216000,"aggregatedStats":{}},{"playerStatSummaryType":"RankedTeam5x5","wins":3,"losses":0,"modifyDate":1383784473000,"aggregatedStats":{"totalChampionKills":28,"totalMinionKills":636,"totalTurretsKilled":6,"totalNeutralMinionsKilled":101,"totalAssists":41}},{"playerStatSummaryType":"Unranked3x3","wins":9,"modifyDate":1421882181000,"aggregatedStats":{"totalChampionKills":90,"totalMinionKills":1427,"totalTurretsKilled":11,"totalNeutralMinionsKilled":428,"totalAssists":105}},{"playerStatSummaryType":"URF","wins":4,"modifyDate":1435024847000,"aggregatedStats":{"totalChampionKills":68,"totalMinionKills":642,"totalTurretsKilled":14,"totalNeutralMinionsKilled":182,"totalAssists":55}},{"playerStatSummaryType":"Unranked","wins":566,"modifyDate":1435549418000,"aggregatedStats":{"totalChampionKills":8419,"totalMinionKills":128213,"totalTurretsKilled":960,"totalNeutralMinionsKilled":26117,"totalAssists":7812}}]}
Heres the link of the second JSON data I want to parse (just adding it, could be useful, but not sure):
https://na.api.pvp.net/api/lol/na/v1.3/stats/by-summoner/43993167/summary?season=SEASON2015&api_key=(took-out-my-private-api-key-for-obvious-reasons)
The link doesn't work because I have to keep my api key private to myself, but the JSON data that it displays is right above the link, which is the what it would result if you were to use the link with the api key.
Just to restate, I would like to process the second part (above of this) of JSON data, but I do not understand how to process multiple links of JSON. I have the first JSON data parsed, but am unable to parse the second JSON data.

I believe Apple is deprecating NSURLConnection. Take a look at NSURLSession. Using it, you can pass in a completion block that takes three arguments: NSData?, NSURLResponse?, and NSError?. The data object contains the JSON you can pass into the JSON serializer. After that, if you need to make another network call, just call it from inside the completion block with another NSURLSession data task. Alamofire is a great framework, but sometimes you don't need everything it provides, and it adds complexity into your app that if something goes wrong or doesn't behave the way you intend/understand, you may not fully understand why. If you want to keep it simple and under your control, use NSURLSession.
let session = NSURLSession.sharedSession()
let task = session.dataTaskWithURL(url) { data, response, error in
// cast response as NSHTTPURLResponse and switch on statusCode if you like
// parse JSON using NSJSONSerialization if you've got data
// spawn off another network call here if you like
}
task.resume() // or in Swift 2, task?.resume()

First, i would totally prefer using some common frameworks for http requests - expecially if youre new in swift. For example here with alamofire.
https://github.com/Alamofire/Alamofire
There is also a version with integrated SwiftyJSON, so you are able to parse JSON Responses very easily.
https://github.com/SwiftyJSON/Alamofire-SwiftyJSON
So if you want to make a request, use this:
Alamofire.request(.GET, "http://httpbin.org/get")
.responseJSON { (_, _, json, _) in
var json = JSON(json)
// get the id out (depends on your structure of JSON):
let id = json["id"].int
}
Now you are able to perform a second Request (with the same Code) - Read the Documentation, how to make different Requests (like with POST) and add Parameters.
If you want to use Segues, so you want to load more data from the ID in another ViewController, you can use Segues to push the data to a second ViewController, and Load the new Content from JSON when the new ViewController is initialised.
Check out this how to send data through segues:
Sending data with Segue with Swift

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