WKWebView Persistent Storage of Cookies

Question

I am using a WKWebView in my native iPhone application, on a website that allows login/registration, and stores the session information in cookies. I am tryin

Answer 1

After days of research and experiments, I have found a solution to manage sessions in WKWebView, This is a work around because I didn’t find any other way to achieve this, below are the steps:

First you need to create methods to set and get data in user defaults, when I say data it means NSData, here are the methods.

+(void)saveDataInNSDefault:(id)object key:(NSString *)key{
    NSData *encodedObject = [NSKeyedArchiver archivedDataWithRootObject:object];
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    [defaults setObject:encodedObject forKey:key];
    [defaults synchronize];
}

+ (id)getDataFromNSDefaultWithKey:(NSString *)key{
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    NSData *encodedObject = [defaults objectForKey:key];
    id object = [NSKeyedUnarchiver unarchiveObjectWithData:encodedObject];
    return object;
}

For maintaining session on webview I made my webview and WKProcessPool singleton.

- (WKWebView *)sharedWebView {
    static WKWebView *singleton;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        WKWebViewConfiguration *webViewConfig = [[WKWebViewConfiguration alloc] init];
        WKUserContentController *controller = [[WKUserContentController alloc] init];

        [controller addScriptMessageHandler:self name:@"callNativeAction"];
        [controller addScriptMessageHandler:self name:@"callNativeActionWithArgs"];
        webViewConfig.userContentController = controller;
        webViewConfig.processPool = [self sharedWebViewPool];

        singleton = [[WKWebView alloc] initWithFrame:self.vwContentView.frame configuration:webViewConfig];

    });
    return singleton;
}

- (WKProcessPool *)sharedWebViewPool {
    static WKProcessPool *pool;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{

        pool = [Helper getDataFromNSDefaultWithKey:@"pool"];

        if (!pool) {
            pool = [[WKProcessPool alloc] init];
        }

    });
    return pool;
}

In ViewDidLoad, I check if it’s not the login page and load cookies into HttpCookieStore from User Defaults so It will by pass authentication or use those cookies to maintain session.

if (!isLoginPage) {
            [request setValue:accessToken forHTTPHeaderField:@"Authorization"];

            NSMutableSet *setOfCookies = [Helper getDataFromNSDefaultWithKey:@"cookies"];
            for (NSHTTPCookie *cookie in setOfCookies) {
                if (@available(iOS 11.0, *)) {

                    [webView.configuration.websiteDataStore.httpCookieStore setCookie:cookie completionHandler:^{}];
                } else {
                    // Fallback on earlier versions
                    [[NSHTTPCookieStorage sharedHTTPCookieStorage] setCookie:cookie];
                }
            }
        }

And, Load the request.

Now, we will maintain webview sessions using cookies, so on your login page webview, save cookies from httpCookieStore into user defaults in viewDidDisappear method.

- (void)viewDidDisappear:(BOOL)animated {

    if (isLoginPage) { //checking if it’s login page.
        NSMutableSet *setOfCookies = [Helper getDataFromNSDefaultWithKey:@"cookies"]?[Helper getDataFromNSDefaultWithKey:@"cookies"]:[NSMutableArray array];
        //Delete cookies if >50
        if (setOfCookies.count>50) {
            [setOfCookies removeAllObjects];
        }
        if (@available(iOS 11.0, *)) {
            [webView.configuration.websiteDataStore.httpCookieStore getAllCookies:^(NSArray * _Nonnull arrCookies) {

                for (NSHTTPCookie *cookie in arrCookies) {
                    NSLog(@"Cookie: \n%@ \n\n", cookie);
                    [setOfCookies addObject:cookie];
                }
                [Helper saveDataInNSDefault:setOfCookies key:@"cookies"];
            }];
        } else {
            // Fallback on earlier versions
            NSArray *cookieStore = NSHTTPCookieStorage.sharedHTTPCookieStorage.cookies;
            for (NSHTTPCookie *cookie in cookieStore) {
                NSLog(@"Cookie: \n%@ \n\n", cookie);
                [setOfCookies addObject:cookie];
            }
            [Helper saveDataInNSDefault:setOfCookies key:@"cookies"];
        }
    }

    [Helper saveDataInNSDefault:[self sharedWebViewPool] key:@"pool"];
}

Note: Above method is tested for iOS 11 only, although I have written fallback for lower versions also but didn’t test those.

Hope this solves your problems !!! :)