This document provides an overview of OData and how it can be used by iOS developers. OData is a standard protocol for building and consuming RESTful APIs in a simple and uniform manner. It allows for representing and transmitting structured data in JSON and XML formats. The document discusses OData producers and services, how to make requests and parse responses in iOS using the OData client library, and provides resources for learning more about using OData in apps.

1. OData: A primer for iOS developers Glen Gordon Developer Evangelist Microsoft Corporation http://glengordon.name @glengordon

2. Who is this Microsoft guy? I support developer communities in GA, AL, MS I work with developers from all roles: enterprise, consultants, ISVs, students, startups, designers Lots of ways to interface with something Microsoft related .NET, PHP, JavaScript Silverlight, Windows Phone, iOS My goal is to make members of the community successful by introducing new technology or connecting people

3. Agenda The case for OData A look at the format Producers, services and consumers Resources and tips

4. why data services?

5. break data silos

6. == data sharing & integration

7. Requirements for Web Data Services Web friendly, just plain HTTP Uniform patterns Focus on data, not on formats Stay high level, abstract the store

8. data service != gateway to database service interface business logic store

9. odata in 1 slide…

10. OData Uniform way of representing structured data Atom, JSON formats Uniform URI conventions Navigation, filtering, sorting, paging, etc. Uniform operations Addressability GET, POST, PUT, DELETE always mean the same

11. REST: 3 definitions An architectural style for building loosely coupled systems defined by a set of very general constraints (principles) the Web (URI/HTTP/HTML/XML) is an instance of this style The Web used correctly (i.e., not using the Web as transport) HTTP is built according to RESTful principles services are built on top of Web standards without misusing them most importantly, HTTP is an application protocol (not a transport protocol) Anything that uses HTTP and XML (XML without SOAP) XML-RPC was the first approach for this violates REST because there is no uniform interface

12. The name Atom applies to a pair of related standards. The Atom Syndication Format is an XML language used for web feeds, while the Atom Publishing Protocol (AtomPub) is a simple HTTP-based protocol for creating and updating web resources. ATOMPub

13. http://services.odata.org/OData/OData.svc ______________________________________/ | service root URI http://services.odata.org/OData/OData.svc/Category(1)/Products?$top=2&$orderby=name ______________________________________/ _________________/ ________________/ | | | service root URI resource path query options What is a URI?

14. Full SQL like Query “Language”

15. Addressing entities and sets

16. Presentation options

17. Query Options

18. Filter Expressions

19. Filter Methods

20. Examples http://services.odata.org/OData.svc/GetProductsByRating?rating=5 Identifies the "GetProductsByRating" Service Operation and specifies a value of 5 for the "rating" input parameter. Service Operations(Functions)

21. { "d" : { "results": [ { "__metadata": { "uri": "http://services.odata.org/OData/OData.svc/Categories(0)", "type": "DataServiceProviderDemo.Category" }, "ID": 0, "Name": "Food", "Products": { "__deferred": { "uri": "http://services.odata.org/OData/OData.svc/Categories(0)/Products" } } }, { /* another Category Entry */ }, { /* another Category Entry */ }, { /* another Category Entry */ } ], "__count": "3", "__next": "http://services.odata.org/OData/OData.svc$skiptoken=12" } } JSON

22. Producers and Consumers

23. OData Producers Windows Communication Foundation (WCF) SharePoint 2010 IBM WebSphere SQL Azure Windows Azure Table Storage SQL Server Reporting Services Microsoft Dynamics CRM 2011 GeoREST Build your own

24. OData Services ebay Netflix Twitpic Windows Live NerdDinner Open Government Data Initiative Open Science Data Initiative Windows Azure Marketplace DataMarket

25. OData Consumers – End Users Web Browsers Excel 2010 OData Explorer

26. OData Consumers – Client Libraries .NET Javascript PHP Java Windows Phone 7 iOS (Objective C) Ruby Joomla Drupal

28. SharePoint 2010

29. SQL Server Reporting Services 2008 R2

30. SQL Azure

31. IBM WebSphereeXtremeScale

32. Microsoft Media Room

34. Mix 2010

35. Nerd Dinner

36. Vancouver’s vanGuide

37. Open Government Data Initiative

38. Open Science Data Initiative

39. Microsoft Codename “Dallas”

41. LINQPad

43. Silverlight

44. Windows Phone 7 Series

45. Javascript

46. Java

47. Objective-C

48. PHPhttp://odata.org/consumers

49. OData and iOS

50. OData and iOS http requests Parse XML or JSON OR Use the OData Client for Objective-C http://odataobjc.codeplex.com/

51. demos

52. Resources All things OData: http://odata.org Email: glen.gordon@microsoft.com Blog: http://glengordon.name Data @ MSDN: http://msdn.com/data

53. © 2010 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.