Connecting to a Curam REST API using Swift for Apple iOS

Connecting programmatically to a Cúram REST API resource depends on the programming language used. The following is an example using the Apple Swift Language for iOS.

1. Create a LoginService.swift class file in your project to handle the Cúram authentication code.
2. Define the following variables in the LoginService.swift class:

   var username = ""
   var password = ""
   var data: NSMutableData = NSMutableData()
   
   // Used for Weblogic
   var WL_JSESSION_ID: String  = ""
   var JSESSION_ID: String = ""
   
   // Used for Websphere
   struct LTPAToken {
     static var ltpaToken2:String = ""
   }
   

3. Define the invokeLoginService() function, which will eventually be called to initiate a login request. The function takes three parameters:
   • username

     The user name to log in.

   • password

     The password to log in.

   • loadTokenUrl

     The full qualified URL for the login, that is, https://host:port/Rest/j_security_check

   func invokeLoginService(username: String, password: String, loadTokenUrl: String)
       {
           let nsUrl = NSURL(string: loadTokenUrl as String );
           self.username = username
           self.password  = password
           NSLog(loadTokenUrl)
           let request = NSMutableURLRequest(URL:nsUrl!);
           request.HTTPMethod = "POST";
           request.HTTPShouldHandleCookies = true
           request.setValue("application/x-www-form-urlencoded", forHTTPHeaderField: "Content-Type")
           //set Referer for CSRF
           request.setValue("curam://foundational.app", forHTTPHeaderField: "Referer")
           let postString = "j_username=" + username + "&j_password=" + password ;
           request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding);
           //invoke login request
           var connection: NSURLConnection = NSURLConnection(request: request, delegate: self, startImmediately: true)!
           connection.start()
       }
   

   The delegate argument in the NSURLConnection object defines that the LoginService (self) class should handle the response from the login request. Next, define the following connection functions to support this.

4. Define a connection function to handle when the connection request is completed. This function sets the necessary cookies if the request was successful.

   func connection(connection:NSURLConnection, didReceiveResponse response: NSURLResponse) {
           let status = (response as? NSHTTPURLResponse)?.statusCode ?? -1
           NSLog("status code is \(status)")
           
           if ( status == 200 )
           {
               //200 OK authentication successful, fetch the LTPAToken2 from response and set for future requests
               self.data = NSMutableData()
               let cookieStorage = NSHTTPCookieStorage.sharedHTTPCookieStorage()
               let allCookies = cookieStorage.cookiesForURL(response.URL!) as! [NSHTTPCookie]
               
               var cookieProperties = [String: AnyObject]()
               for cookie in allCookies {
                   cookieProperties[NSHTTPCookieName] = cookie.name
                   cookieProperties[NSHTTPCookieValue] = cookie.value
                   println("name: \(cookie.name) value: \(cookie.value)")
                   if ( cookie.name == "LtpaToken2" )
                   {
                        LTPAToken.ltpaToken2 = cookie.value!
                   }
               }
               let success = [ 200,  "Success"]
               return
           }
               
           else if ( status == ErrorCodeConstants.errAuthenticationFailure )
           {
               //authentication error
               let error = [ 401,  "LoginErrorMsg3"]
               return
           }
           else
           {
               let error = [ 600,  "LoginErrorMsg2"]
               return
           }
   }
   
   

5. Define a connection function to handle the data that is returned by the request.

       func connection(connection: NSURLConnection, didReceiveData connectionData: NSData) {
           // Append the received chunk of data to our data object
           self.data.appendData(connectionData)
       }
   

6. Define a connection function to handle an unsuccessful response.

   func connection(connection: NSURLConnection, didFailWithError connectionData: NSError) {
           // Append the received chunk of data to our data object
           NSLog("didFailWithError ---> \(connectionData)")
           return
       }
   

7. Use the newly created LoginService.swift class within your project to initiate authentication.
   For example, from a view controller, use the following:

   var username = “planner”
   var password = “password”
   var loginURL = “https://host:port/Rest/j_security_check
   let loginService = LoginService()
   loginService.invokeLoginService (username, password, loginURL)
   

8. In your project, use the following code to invoke the GET method of the Cúram persons REST API resource. This code uses the previously defined loginService variable.

   
           let url  = NSURL(string: curamServerURI+"/v1/persons/101")
           let request = NSMutableURLRequest(URL:url!);
           request.HTTPMethod = "GET"
           let config = NSURLSessionConfiguration.defaultSessionConfiguration()
           //set the headers , this can be moved in a common method, when there are more apis to invoke
           var xHTTPAdditionalHeaders: [NSObject : AnyObject] = ["Content-Type": "application/json", "Accept": "application/json"]
           //set the headers for LTPAToken if it is for WAS else for WLS , you need to set the _WL_AUTHCOOKIE_JSESSIONID & JSESSIONID
           xHTTPAdditionalHeaders["Cookie"] = "LtpaToken2="+LoginService.LTPAToken.ltpaToken2+";"
           //set Referer for CSRF
           xHTTPAdditionalHeaders["Referer"]  =  "curam://foundational.app"
           config.HTTPAdditionalHeaders = xHTTPAdditionalHeaders
           
           let session = NSURLSession(configuration: config)
           var err: NSError?
           let task : NSURLSessionDataTask = session.dataTaskWithRequest(request, completionHandler: {(data, response, error) in
               let status = (response as? NSHTTPURLResponse)?.statusCode ?? -1
               self.data = NSMutableData()
               if (status == 200)
               {
                   //200 OK..request successful .... process response
                   println("Response: \(response)")
                   var strData = NSString(data: data, encoding: NSUTF8StringEncoding)
                   println("Body: \(strData)")
                   var err: NSError?
                   if let jsonResult = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: &err) as? NSDictionary {
                       if(err != nil) {
                           // If there is an error parsing JSON, print it to the console
                           println("JSON Error \(err!.localizedDescription)")
                       }
                       if let results: NSArray = jsonResult["relationships"] as? NSArray {
                           dispatch_async(dispatch_get_main_queue(), {
                               println("Person Relationship data :\(results)")
                           })
                       }
                   }
               }
               else
               {
                   let error = [ 600,  "Request failed"]
                   println("Request failed Error \(self.data)")
                   
               }
           })
           //start the service request
           task.resume()