Web API for MobileJaxARCSIG April 2012

About MeDavid Fekke L.L.C.Mobile apps for iOSRegular presenter at JaxDUG, JSSUG and JaxFusionWriting Web Services for over 10 years

History of Web Services1989 - Tim Berners-Lee invents HTTP/HTML1998 - XML 1.0, SOAP begins ratification2001 - SOAP standard2000 - Fielding dissertation on REST

SOAPSimple Object Access ProtocolUses a standard XML Schema over HTTPExtremely cross platform compatibleExtremely Slow

RESTRepresentable State TransferUses standard HTTPCan use any text format including XML

XML vs JSONXML tag based document formattingJavascript Notation by Douglas CrockfordJSON less verbose than XML, more lightweightMobile devices have limited bandwidth

Public APIsTwitterFacebookFlickrAmazoniTunes

WebAPIAvailable now as Nuget PackageBuilt-in as part of MVC 4Take advantage of HTTP features directly

HTTP methods as ActionsDefault route will use http method for actionController/action/idAPI/Controller/id GET/POST/PUT/DELETE

HTTP Method meaningsGet - Return an existing documentPost - Create a new documentPut - Update a documentDelete - Self explanatory

Configure TransportSet Xml or JSON based on Content-Type or Accept headerAccept: application/xmlCan also use Odata

Return CodesNow have the ability to specify return codes beside 200HttpResponseMessageHttpStatusCode.Created 201response.Headers.Location = new Uri()

Http Status codes201 Created200 Success/204 Success but No Content 403 Not authorized404 Does not exist500 Server Error301 Uri Moved

Security[Authorize()]https over port 443Security TokensOAuth

Testing WebAPIDownload Fiddler2Firebug (Firefox)ChromeOn Mac use CocoaRestClient

Consuming WebAPIWeb Apps (ASP.NET, MVC, PHP, Java, ColdFusion, Ruby(Rails), Python, Perl(if you are masochistic))JavaScript/JQueryMobile (iOS, Android, WP7, Blackberry OS)

Develop WebAPI and iOS on Same ComputerParallels or VMWareSet Network Adapter to BridgedRun Visual Studio as AdministratorHost on IIS (do not use IIS Express or Casini)

Consuming WebAPI in iOSUse NSURLConnection delegate or GCDShow progress while waiting on responseUse JSON over XMLNSJSONSerialization class (new in iOS 5)

XML Parsing in iOSNSXMLParser (Slowest)libxml2 (C api)TBXML (DOM, Fastest, no write or xpath)TouchXML (DOM supports xpath, no write)KissXML (based on Touch, can write)GDataXML (DOM, from Google)RaptureXML (DOM, supports xpath)

Call WebAPI from AndroidCreate DefaultHttpClient();Create request with HttpGet(Url);Create response handler BasicResponseHandler();httpClient.execute(request, handler);

JSON in Androiduse the JSONObject to parseJSONObject jo = new JSONObject(jString); jo.getJSONObject(car);jo.getJSONArray(cars);

XML Parsing in AndroidDOM, SAX and PullW3C Dom parserStandard Java Sax ParserSJXP (Pull parser)

WebAPI as persistenceDont use WebAPI as default persistence on MobileBoth Android and iOS have device persistencelocal storage, CoreData and SQLiteiCloud to sync between iOS devices

Demo

Questions

Contact InfoDavid Fekkefekke.com/blogdavid fekke at gmail dot comtwitter @davidfekkeaim: davefekke