Form-based authentication in native iOS applications

improve this page | report issue

Overview

This tutorial explains how to implement the client-side of form-based authentication in native iOS.
Prerequisite: Make sure that you read the Form-based authentication tutorial first.

Implementing the client-side authentication

Create a native iOS application and add the MobileFirst native APIs as explained in the Configuring a native iOS application with the MobileFirst Platform SDK tutorial.

Storyboard

In your storyboard, add a View Controller containing a login form.

missing_alt

Challenge Handler

  • Create a MyChallengeHandler class as a subclass of ChallengeHandler.

    @interface MyChallengeHandler : ChallengeHandler
  • Call the initWithRealm method:
    @implementation MyChallengeHandler
    //...
    -(id)init:{
        self = [self initWithRealm:@"SampleAppRealm"];
        return self;
    }
  • Add an implementation of the following ChallengeHandler methods to handle the form-based challenge:
    1. isCustomResponse method:
      The isCustomResponse method is invoked each time a response is received from the MobileFirst Server. It is used to detect whether the response contains data that is related to this challenge handler. It must return either true or false.
      The default login form that returns from the MobileFirst Server contains the j_security_check string. If the response contains the string, the challenge handler returns true.
      -(BOOL) isCustomResponse:(WLResponse *)response {
          if(response && response.responseText){
              if ([response.responseText rangeOfString:@"j_security_check" options:NSCaseInsensitiveSearch].location != NSNotFound) {
                  NSLog(@"Detected j_security_check string - returns true");
                  return true;
              }
          }
          return false;
      }
    2. handleChallenge method:
      If isCustomResponse returns true, the framework calls the handleChallenge method. This function is used to perform required actions, such as hiding the application screen and showing the login screen.

      -(void) handleChallenge:(WLResponse *)response {
          NSLog(@"A login form should appear");
          LoginViewController* loginController = [self.vc.storyboard instantiateViewControllerWithIdentifier:@"LoginViewController"];
          loginController.challengeHandler = self;
          [self.vc.navigationController pushViewController:loginController animated:YES];
      }
    3. onSuccess and onFailure methods:
      At the end of the authentication flow, onSuccess or onFailure will be triggered
      Call the submitSuccess method in order to inform the framework that the authentication process completed successfully and for the onSuccess handler of the invocation to be called.
      Call the submitFailure method in order to inform the framework that the authentication process failed and for the onFailure handler of the invocation to be called.

      -(void) onSuccess:(WLResponse *)response {
          NSLog(@"Challenge succeeded");
          [self.vc.navigationController popViewControllerAnimated:YES];
          [self submitSuccess:response];
      }
      -(void) onFailure:(WLFailResponse *)response {
          NSLog(@"Challenge failed");
          [self submitFailure:response];
      }


submitLoginForm

In your login View Controller, when the user taps to submit the credentials, call the submitLoginForm method to send the j_security_check string and the credentials to the MobileFirst Server.

@implementation LoginViewController
//...
- (IBAction)login:(id)sender {
    [self.challengeHandler submitLoginForm:@"j_security_check"
         requestParameters:@{@"j_username": self.username.text, @"j_password": self.password.text}
         requestHeaders:nil
         requestTimeoutInMilliSeconds:0
         requestMethod:@"POST"];
}
@end


The Main ViewController

In the sample project, in order to trigger the challenge handler we use the WLClient invokeProcedure method.
The protected procedure invocation triggers MobileFirst Server to send the challenge.

  • Create a WLClient instance and use the connect method to connect to the MobileFirst Server:
        MyConnectListener *connectListener = [[MyConnectListener alloc] init];
        [[WLClient sharedInstance] wlConnectWithDelegate:connectListener];
  • In order to listen to incoming challenges, make sure to register the challenge handler by using the registerChallengeHandler method:
        [[WLClient sharedInstance] registerChallengeHandler:[[MyChallengeHandler alloc] initWithViewController:self] ];
  • Invoke the protected adapter procedure:
        NSURL* url = [NSURL URLWithString:@"/adapters/AuthAdapter/getSecretData"];
        WLResourceRequest* request = [WLResourceRequest requestWithURL:url method:WLHttpMethodGet];
        [request sendWithCompletionHandler:^(WLResponse *response, NSError *error) {
        ...
        }];

Sample application

Click to download the MobileFirst project.
Click to download the Objective-C project.
Click to download the Swift project.

  • The FormBasedAuth project contains a MobileFirst native API that you can deploy to your MobileFirst server.
  • The FormBasedAuthObjC and FormBasedAuthSwift projects contains a native iOS application that uses a MobileFirst native API library.
  • Make sure to update the worklight.plist file in the native project with the relevant server settings.

missing_alt

Inclusive terminology note: The Mobile First Platform team is making changes to support the IBM® initiative to replace racially biased and other discriminatory language in our code and content with more inclusive language. While IBM values the use of inclusive language, terms that are outside of IBM's direct influence are sometimes required for the sake of maintaining user understanding. As other industry leaders join IBM in embracing the use of inclusive language, IBM will continue to update the documentation to reflect those changes.
Last modified on November 09, 2016