Come hear how to work with external REST, SOAP, and Windows Communication Foundation (WCF) services from Silverlight. Learn how to securely and efficiently communicate with services using Binary XML, debug services with improved Faults support, and implement server-to-client "push" using the new Add Service Reference for Duplex functionality.

3. Simple Back-End Data Access
WCF,
SOAP
“Data Push” (Server to Client)
WCF
Mashups (Using REST APIs)
REST,
XML/JSON,
Atom/RSS

4. Simple Back-End Data Access
WCF,
SOAP
“Data Push” (Server to Client)
WCF
Mashups (Using REST APIs)
REST,
XML/JSON,
Atom/RSS

7. System.ServiceModel.CommunicationException: The remote
server returned an error: NotFound

11. Binary XML

12. “Silverlight-enabled WCF Service”
- now Binary by default

13. Using quot;typicalquot; message payloads
HP BL680c: 8 Intel EMT64 cores@2.4GHz
Windows Server 2008 64-bit, IIS7
Text / HTTP
Web service requests/sec
24% Binary / HTTP
7570
6122
71% 4615
2702
Your mileage may vary
20 objects 100 objects
Message size

14. Using large messages with arrays of quot;typicalquot; data
40%
34%
Size reduction
15%
Your mileage may vary
String Int Large object graph

16. Attempt #1: Naïve Approach

18. Attempt #2: Enable Debugging

19. Error info still not in Silverlight!
System.ServiceModel.CommunicationException: The remote
server returned an error: NotFound

20. HTTP 500
HTTP 200
http://code.msdn.com/SilverlightWS

21. HTTP 200

22. With Silverlight 3 Faults Support

25. Example with Cookies + Forms Auth
E.g.: ASP.NET login
Credentials
User:
YourDomain.com
Password:
Auth info (cookie)
Service calls + Auth info
Browser

26. Login through Silverlight
Call with credentials to YourDomain.com
User: ASP.NET Auth Service
Password: ASP.NET
Reply contains cookie Auth Service
Service calls + Auth info
Browser

27. Using Windows Authentication
Windows login
User:
YourDomain.com
Password:
Service calls + Creds
Browser

28. Cross-Domain Threat
MyBank.com Login
Credentials
User:
MyBank.com
Password:
Auth info (e.g. cookie)
Could steal or
change data
Malicious call + Auth info if protection
wasn’t in place
Malicious application
EvilApps.com

30. Identity managed by Silverlight, not the Browser
YourDomain.com
User:
Password:
Creds are added by
Silverlight, not browser
No
creds
EvilApps.com
Browser

31. [OperationContract]
public decimal GetAccountBalance
(int accountID, string userName, string password);

33. <!-- WS-Security Header -->
<!-- With UserName, Password, Timestamp -->
<!-- Message Payload -->
Default max skew is 5 minutes – may require changes
(Client clock can’t be more that 5 minutes out of sync with server)

35. sl

37. Simple Back-End Data Access
WCF,
SOAP
“Data Push” (Server to Client)
WCF
Mashups (Using REST APIs)
REST,
XML/JSON,
Atom/RSS

40. EndpointAddress address = new
EndpointAddress(quot;http://example.com/Service1.svcquot;);
CustomBinding binding = new CustomBinding(
new PollingDuplexBindingElement(),
new TextMessageEncodingBindingElement(
MessageVersion.Soap12WSAddressing10, Encoding.UTF8),
new HttpTransportBindingElement());

41. CallbackContract=…
IsOneWay=true
GetCallbackChannel

42. Simple Back-End Data Access
WCF,
SOAP
“Data Push” (Server to Client)
WCF
Mashups (Using REST APIs)
REST,
XML/JSON,
Atom/RSS

45. HTML DOM + JavaScript XmlHttpRequest
Proxied through a Service

46. “Paste XML as Serializable Types”

48. Simple Back-End Data Access
WCF,
SOAP
“Data Push” (Server to Client)
WCF
Mashups (Using REST APIs)
REST,
XML/JSON,
Atom/RSS

50. Your feedback is important!

51. © 2009 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.
The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market
conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation.
MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

53. High-level components and User Code
HttpWebRequest
Browser Plugin APIs Restrictions
Web Browser
- Cookies
- Authenticated sessions Restrictions
- Caching
- Proxy server to use
Windows/Mac
Networking Layer

54. Client Client Any messages? Server Server
App Duplex Duplex App
Channel 10-15sec Channel
No messages
Any messages?
Message
Message Message
Any messages?
Client Browser Server