Download/Upload File Using WCF REST Services With Windows Authentication

WCF REST Service

1. Add a new Blank solution by the name of “FileHandling”.
2. Add a new WCF Service Application and give it the name FileHandling.WCFHost.
   
   
   
3. Right-click the FileHandling.WCFHost project in Visual Studio and go to the properties. Under the Web tab click on “Use local IIS WebServer” and under the Project URL, write “http://localhost/FileHandling.WCFHost” and click on the button “Create Virtual Directory”. This will create a Virtual Directory for FileHandling.WCFHost in IIS.
   
   
   
4. Go to IIS and check if the Virtual Directory is created.
   
   
   
5. Ensure that the App Pool associated to the account is of .Net Framework 4.0. Also, the App Pool should be running under the identity of the user that has Read/write rights on any folder of the server. WCF uses this identity for doing all its network operations. In this case I run the App Pool under my account, but it is not mandatory, you can choose a different account having permissions as well.
   
   
   
   
6. Ensure that for the FileHandling.WCFHost, only Windows Authentication is enabled.
   
   
   
   With the preceding steps the IIS configuration is complete. Now it's time to add the service.
   
7. Add a new WCFService in the FileHost.WCFHost project in VisualStudio and give it the name FileManagerService.
   
   
   
8. In the IFileManagerService add the following methods.
   
   1. using System.IO;
   2. using System.ServiceModel;
   3. using System.ServiceModel.Web;
   5. namespace FileHandling.WCFHost
   6. {
   7. [ServiceContract]
   8. public interface IFileManagerService
   9. {
   11. [OperationContract]
   12. [WebGet(UriTemplate = "RetrieveFile?Path={path}")]
   13. Stream RetrieveFile(string path);
   15. [OperationContract]
   16. [WebInvoke(UriTemplate = "UploadFile?Path={path}")]
   17. void UploadFile(string path, Stream stream);
   19. }
   20. }
       
9. In the FileManagerService.svc.cs add the following code:
   
   1. using System;
   2. using System.IO;
   3. using System.ServiceModel.Web;
   5. namespace FileHandling.WCFHost
   6. {
   7. public class FileManagerService : IFileManagerService
   8. {
   9. public Stream RetrieveFile(string path)
   10. {
   11. if(WebOperationContext.Current == null) throw new Exception("WebOperationContext not set");
   13. // As the current service is being used by a windows client, there is no browser interactivity.
   14. // In case you are using the code Web, please use the appropriate content type.
   15. var fileName = Path.GetFileName(path);
   16. WebOperationContext.Current.OutgoingResponse.ContentType= "application/octet-stream";
   17. WebOperationContext.Current.OutgoingResponse.Headers.Add("content-disposition", "inline; filename=" + fileName);
   19. return File.OpenRead(path);
   20. }
   22. public void UploadFile(string path, Stream stream)
   23. {
   24. CreateDirectoryIfNotExists(path);
   25. using (var file = File.Create(path))
   26. {
   27. stream.CopyTo(file);
   28. }
   29. }
   31. private void CreateDirectoryIfNotExists(string filePath)
   32. {
   33. var directory = new FileInfo(filePath).Directory;
   34. if (directory == null) throw new Exception("Directory could not be determined for the filePath");
   36. Directory.CreateDirectory(directory.FullName);
   37. }
   38. }
   39. }
       
   The RetrieveFile method is used for downloading the file. The method takes the parameter “path”, that is the location of the file for downloading from the WCF server. The method itself is pretty simple, it sets the ContentType and filename in the Response Header and then sends the FileStream back. Do not worry about how this FileStream will be disposed. WCF automatically takes care of it and at the end of the method disposes of it.
   
   The UploadFile is also pretty simple. It takes the following two parameters:
   
   
   • path: Path where the uploaded file should be saved
   • stream: Stream represents the Uploaded file.
   
   The method creates the Directory if it does not already exist and then creates the file in the location specified by “path”. For copying the uploaded file in the “path” location, Stream.CopyTo has been used.
   
10. It's time to add the configuration settings for the service. In the Web.Config add the following configuration.
    
    1. <system.serviceModel>
    2. <serviceHostingEnvironment multipleSiteBindingsEnabled="true" />
    3. <bindings>
    4. <webHttpBinding>
    5. <binding name="ServiceWebBindingName" transferMode="Streamed" maxReceivedMessageSize="2147483647" >
    6. <readerQuotas maxArrayLength="2147483647" maxStringContentLength="2147483647" />
    7. <security mode="TransportCredentialOnly">
    8. <transport clientCredentialType="Windows"></transport>
    9. </security>
    10. </binding>
    11. </webHttpBinding>
    12. </bindings>
    13. <behaviors>
    14. <endpointBehaviors>
    15. <behavior name="DefaultRestServiceBehavior">
    16. <webHttp defaultOutgoingResponseFormat="Json" defaultBodyStyle="Wrapped" automaticFormatSelectionEnabled="false"/>
    17. </behavior>
    18. </endpointBehaviors>
    19. <serviceBehaviors>
    20. <behavior name="">
    21. <serviceMetadata httpGetEnabled="true" />
    22. <serviceDebug includeExceptionDetailInFaults="true" />
    23. </behavior>
    24. </serviceBehaviors>
    25. </behaviors>
    26. <services>
    27. <service name="FileHandling.WCFHost.FileManagerService">
    28. <endpoint address=""
    29. binding="webHttpBinding"
    30. bindingConfiguration="ServiceWebBindingName"
    31. behaviorConfiguration="DefaultRestServiceBehavior"
    32. name="FileManagerServiceEndpoint"
    33. contract="FileHandling.WCFHost.IFileManagerService"/>
    34. </service>
    35. </services>
    36. </system.serviceModel>
    37. </configuration>
        
    Please note that the Transfermode has been set to “Streamed”. This will ensure that the file is streamed to the client. And also, notice that I have given maximum values to maxReceivedMessageSize, maxArrayLength, maxStringContentLength. This will ensure that large files can be transferred as well.
    
    1. <binding name="ServiceWebBindingName" transferMode="Streamed" maxReceivedMessageSize="2147483647" >
    2. <readerQuotas maxArrayLength="2147483647" maxStringContentLength="2147483647" />
    3. <security mode="TransportCredentialOnly">
    4. <transport clientCredentialType="Windows"></transport>
    5. </security>
    6. </binding>
    7. </webHttpBinding>
    8. </bindings>
       
    Also note that for Security mode has been set to TransportCredentialsOnly and the ClientCredentialType has been set to Windows.