使用API Key验证WCF Data Service

Ron Jacobs 有篇文章介绍如何在WCF Rest Service中使用API Key验证：http://blogs.msdn.com/b/rjacobs/archive/2010/06/14/how-to-do-api-key-verification-for-rest-services-in-net-4.aspx ，在WCF Data Service中怎么做呢？本文将介绍如何在WCF Data Service中使用API Key进行验证，主要代码来自于Ron Jacobs的这篇文章.

API Key作为一个参数在URL中传递， 在Rob Jacobs的WCFWebHttpLibrary.APIKeyAuthorization的方法string GetAPIKey(OperationContext operationContext)的代码如下：

   1: public string GetAPIKey(OperationContext operationContext)

   2: {

   3:   // Get the request message

   4:   var request = operationContext.RequestContext.RequestMessage;

   5:   // Get the HTTP Request

   6:   var requestProp =(HttpRequestMessageProperty)request.Properties[HttpRequestMessageProperty.Name];

   7:   // Get the query string

   8:   NameValueCollection queryParams =

   9:       HttpUtility.ParseQueryString(requestProp.QueryString);

  10:  

  11:   // Return the API key (if present, null if not)

  12:   string apiKey = queryParams[APIKEY];

  13:   // Is the API Key available in the querystring?

  14:   if (apiKey == null)

  15:   {

  16:     // Is the API Key available in the header?

  17:     apiKey = requestProp.Headers[APIKEY];

  18:   }

  19:   return apiKey;

  20: }

WCF Data Service的OnStartProcessingRequest 方法在处理每个请求之前调用。对于批处理请求，将会为顶级批处理请求调用一次，然后为批处理中的每个操作调用一次。 我们在这个方法里可以实施自定义验证的相关逻辑：

   1: protected override void OnStartProcessingRequest(ProcessRequestArgs args)

   2: {

   3:    var queryParams = HttpUtility.ParseQueryString(args.OperationContext.AbsoluteRequestUri.Query);

   4:    string apiKey = queryParams[APIKEY];

   5:    if (apiKey == null)

   6:    {

   7:         apiKey = args.OperationContext.RequestHeaders[APIKEY];

   8:    }

   9:    if (CheckValidAPIKey(apiKey)) 

  10:    {

  11:       base.OnStartProcessingRequest(args);

  12:    }

  13:    else

  14:    {

  15:        throw new System.Web.Services.Protocols.SoapException();

  16:    }

  17:  

  18: }

  19:  

客户端调用的时候，可以在SendingRequest事件添加到请求的Header里头：

   1: class Program

   2: {

   3:         static void Main(string[] args)

   4:         {

   5:             Uri serviceUri = new Uri("http://localhost/ProfilesDataService");

   6:  

   7:             ServiceReference.YUPEntities service = new ServiceReference.YUPEntities(serviceUri);

   8:             service.SendingRequest += new EventHandler<System.Data.Services.Client.SendingRequestEventArgs>

   9:  

  10: (service_SendingRequest);

  11:  

  12:             var items = service.Execute<UserProfile>(new Uri(http://localhost/ProfilesDataService/GetUserProfile?username='testvip')).ToList();

  13:             foreach (UserProfile profile in items)

  14:             {

  15:                 Console.WriteLine(profile.Title);

  16:             }

  17:         }

  18:  

  19:         static void service_SendingRequest(object sender,System.Data.Services.Client.SendingRequestEventArgs e)

  20:         {

  21:             // when using api in the header...

  22:             e.Request.Headers.Add("APIkey", "918704ec-4811-45b6-a169-16bae3df69a8");

  23:  

  24:         }

  25:  

  26: }