Windows 8 Web Sevices

This Presentation talks about how to create your first web service in windows 8 applications and using the bing translator API as an example

Transcript

1. Microsoft Student Partners Windows 8 Training How to develop a Windows 8 “Web Service App” ? Example: Bing Translator API
2. Who am I? British University in Egypt Microsoft Student Partner (MSP) Amr Abulnaga
3. Agenda Technical Concepts Bing Translator API Access Token UI Design Connection – Request – Response – Translate Surprise ! Brain Storming “Web Service Apps”
4. Technical Concepts Assets Data Model (Data Layer) -> Data Source App Pages
5. Technical Concepts Languages Supported: WPF & C# HTML & JavaScript WPF & C++
6. Technical Concepts Charms Life Tiles Toast Notifications App Contracts Windows 8 Search Contract
7. Bing Translator API http://api.microsofttranslator.com Bing Translator API (Application Programming Interface) is an online service made for developers to have access to the online Bing Translation service and add it to their applications easily
8. Bing Translator API Bing Translator API is part of Windows Azure marketplace https://datamarket.azure.com/dataset/bing/microsofttranslator To access Bing Translator, it must be authorized via OAuth, and an access_token.
9. Bing Translator API - Access Token What is an access_token? Its an object that contains the security information for a login session identifying the user. How to get an access_token? You must register your application via https://datamarket.azure.com/developer/applications/
10. Bing Translator API - Access Token You’ll be given a Client Secret Key which you’ll use further in your app. Write your Client ID and Application Name and a Redirect URI if available if not then write any valid URL
11. UI Design 1- Now that we have registered our app and reserved an access token let’s start developing the application  2- Drag and drop controls from the Toolbox 3- We will use 3 controls a TextBox to allow the user input string then a TextBlock to output the translated string and a button that when pressed the string will be processed for translation
12. Developing: Connection Double Click on the button, a function opens! Create the request for the OAuth service that will get us our access tokens and the request connection type will be POST.
13. Developing: Connection Code Using Windows.Networking.Connectivity; private async void Button_Click_1(object sender, RoutedEventArgs e) { if (NetworkInformation.GetInternetConnectionProfile() != null && NetworkInformation.GetInternetConnectionProfile().GetNetworkConnectivityLevel() != false && NetworkConnectivityLevel.InternetAccess != false) { // Initialize the strTextToTranslate here, while we're on the UI thread strTextToTranslate = txtbox1.Text; // STEP 1: Create the request for OAuth service that will get us our access tokens. String strTranslatorAccessURI = "https://datamarket.accesscontrol.windows.net/v2/OAuth2-13"; WebRequest req = WebRequest.Create(strTranslatorAccessURI); req.Method = "POST"; req.ContentType = "application/x-www-form-urlencoded"; IAsyncResult writeRequestStreamCallback = (IAsyncResult)req.BeginGetRequestStream(new AsyncCallback(RequestStreamReady), req); } }
14. Developing: Request Now we will use the access token that we created before to complete our request to the azure service using the clientID , the clientSecret and send it in a postStream via a HttpWebRequest
15. Developing: Request Code private void RequestStreamReady(IAsyncResult ar) { string clientID = "dicta123"; string clientSecret = "BJf5LqpyNrFQwANKuoyoUNeHBAGQxpBTtQAwvPd7RLE="; String strRequestDetails = string.Format("grant_type=client_credentials&client_id={0}&client_secret={1}&scope=http ://api.microsofttranslator.com", WebUtility.UrlEncode(clientID), WebUtility.UrlEncode(clientSecret)); System.Net.HttpWebRequest request = (System.Net.HttpWebRequest)ar.AsyncState; byte[] bytes = System.Text.Encoding.UTF8.GetBytes(strRequestDetails); System.IO.Stream postStream = request.EndGetRequestStream(ar); postStream.Write(bytes, 0, bytes.Length); request.BeginGetResponse(new AsyncCallback(GetResponseCallback), request); }
16. Developing: Response This method we will use to get the response from the token after being processed We used the serializer here to read the response stream an then store it in a token The most important part is the translation URI which calls the translator service via a HttpWebRequest and sends the text that needs translation the last part of the URI is what decides the requested language for translation and the current language than the user used “&from=&to=ar” if we left the from empty it will auto detect the language used.
17. Developing: Response Code private void GetResponseCallback(IAsyncResult ar) { HttpWebRequest request = (HttpWebRequest)ar.AsyncState; HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(ar); System.Runtime.Serialization.Json.DataContractJsonSerializer serializer = new System.Runtime.Serialization.Json.DataContractJsonSerializer(typeof(AdmAccessToken)); AdmAccessToken token = (AdmAccessToken)serializer.ReadObject(response.GetResponseStream()); string uri = "http://api.microsofttranslator.com/v2/Http.svc/Translate?text=" + System.Net.WebUtility.UrlEncode(strTextToTranslate) + "&from=&to=ar"; System.Net.WebRequest translationWebRequest = System.Net.HttpWebRequest.Create(uri); string headerValue = "Bearer " + token.access_token; translationWebRequest.Headers["Authorization"] = headerValue; IAsyncResult writeRequestStreamCallback = (IAsyncResult)translationWebRequest.BeginGetResponse(new AsyncCallback(translationReady), translationWebRequest); }
18. Developing: Translation This function retrieves the result translated from the WebResponse as an XML then points to the First node to convert it to string and display it to the user. First we created a response string which carries the response stream Then it was parsed as an XML At last we used the Dispatcher.RunAsync to update part of the page only not to reload all of the page then the translated string appears finally in the text block
19. Developing: Translation Code private async void translationReady(IAsyncResult ar) { HttpWebRequest request = (HttpWebRequest)ar.AsyncState; HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(ar); System.IO.Stream streamResponse = response.GetResponseStream(); System.IO.StreamReader streamRead = new System.IO.StreamReader(streamResponse); string responseString = streamRead.ReadToEnd(); System.Xml.Linq.XDocument xTranslation = System.Xml.Linq.XDocument.Parse(responseString); string strTest = xTranslation.Root.FirstNode.ToString(); await this.Dispatcher.RunAsync(CoreDispatcherPriority.Normal, () => { txtblock1.Text = strTest;}); }
20. Preview
21. Demo Get the Access Token Explore Architecture of a Windows 8 project Add App Assets (Images) Redefine App, Windows Store Data (Package.appxmanifest) Build UI Build connection functions
22. What’s Next! Be What’s Next!
23. What’s Next ? – Windows Store Microsoft Windows Store Guidelines - Windows 8 app certification requirements http://msdn.microsoft.com/en-US/library/windows/apps/hh694083 - Resolving certification errors http://msdn.microsoft.com/en-us/library/windows/apps/hh921583.aspx
24. What’s Next ? – Extra Features Accelerometer sensor - App tiles - Background task - Toast notifications - media playback - Search contract - Trial app and in-app purchase - Snapping - Secondary tiles - Sharing content source - Sharing content target - Responding to the appearance of the on-screen keyboard - Removable Storage - Push and periodic notifications client-side & many more …
25. The Surprise is ……..  !
26. 146 Coding Sample Covering all Windows 8 Features
27. What’s Next ? – Imagine Cup “Windows 8 Apps Challenge”
28. Brainstorming! About Windows 8 “Web Service Apps”
29. Contact me amr.salah@studentpartner.com http://www.facebook.com/amrabulnaga.0 http://www.twitter.com/amrabulnaga http://amrabulnaga.WordPress.com
30. Thank you  Thank you so much!