This post is the continuation of our series: Receiver Internals : How Receiver for HTMl5 & Chrome Connections Work. Today’s post focuses on learning more about the File transfer Capability in Citrix Receiver for HTML5/Chrome.
File Transfer:
File transfer virtual channel has been added to the XenApp and XenDesktop 7.6 FP3 VDA and enabled only with Receiver for HTML5 and Chrome. Using file transfer we can securely transfer files between user device and virtual XenApp and XenDesktop sessions.
File transfer upload or download can be triggered in following two ways with Receiver for HTML5/Chrome:
- By using the session toolbar.
Figure 1 File Download with Toolbar
Figure 2 File Upload with Toolbar
- By ‘drag and drop’ to upload, save file in ‘Save to My Device’ on VDA to trigger download by saving a file and ‘Send To My Device” on right click on file for automatic download to browser’s download folder on client machine.
Figure 3 File Upload with Drag and Drop
Figure 4 File Download with Send To My Device
Figure 5 File Download with Save To My Device
File Transfer Policy Control
File upload and download can be enabled or disabled using Citrix Studio Policy giving the required control to the admin. Admin has to install the Group Policy Management Hotfix 7.6.300 to set these policies. The Studio policies required for file transfer are as follows:
| CITRIX STUDIO POLICY | DESCRIPTION |
| Allow file transfer between desktop and client | To enable or disable file transfer feature |
| Upload file to Desktop | To enable or disable file upload in the session. It requires the “allow file transfer between desktop and client” policy to be set to true. |
| Download file from Desktop | To enable or disable file download from the session. It requires the “allow file transfer between desktop and client” policy to be set to true. |
Note:
By default, File transfer is enabled; to disable it, we need to use the Group Policy, as mentioned above.
If any one of the “Upload file to Desktop” or “Download file from Desktop” policies is disabled, the toolbar will still show the both upload and download icon in the toolbar but the functionality would be enabled based on the policy set. However, if both “Upload file to Desktop” or “Download file from Desktop” policy are disabled, then the upload and download icons will not be seen in the toolbar.
XenDesktop 7.6 Feature Pack 3 VDA, enables the admins to have control over the following file transfer registry settings at the location HKLM\Software\Citrix\FileTransfer:
| FILE TRANSFER REGISTRY SETTINGS | DESCRIPTION | USE CASE |
| CacheFolderLocation | To set the location to which files downloaded are cached in case of “Save to My Device” or “Send to My Device” option. By default it is empty in registry with the default location as “%temp%/CitrixClient” inside the session. | Admin can choose to set the location to which files downloaded are cached. |
| CreateMyDeviceLink | To enable or disable file download with Save to My Device. By default it is enabled. | Admin can choose to allow users to download files on Saving a file by setting this registry. |
| CreateSendToLink | To enable or disable file download with Send To My Device Link. By default it is enabled. | Admin can choose to download files with SendTo by setting this registry. |
| MaxFileSizeDownload | To set the maximum size of the file that can be downloaded in bytes. By default it is set to 262144000 bytes (250MB) | Admin can restrict on the maximum size of a file a user can download from a session. |
| MaxFileSizeUpload |
To set the maximum size of the file that can be uploaded in bytes. By default it is set to bytes 2147483647 (2GB) |
Admin can restrict on the maximum size of file a user can upload to the session. |
| UploadFolderLocation | To set the default location to which the files get uploaded on VDA for all users. By default it prompts the user to choose a location. | If you like files to be uploaded to user’s desktop or some network drive, then this can be set. Users can be educated where the files are saved. This reduces a step for users whenever a file is uploaded |
| MaxFilesInQueue | This specifies the maximum number of files that can be uploaded or downloaded at a time. The default value is 10 and any modification has no effect currently. | Users can upload or download up to 10 files at a time. |
With Receiver for HTML5 and Chrome 1.8 release, following client side settings are available in the configuration.js file:
| FILE TRANSFER CLIENT SETTINGS | DESCRIPTION |
| AllowUpload | To enable or disable upload from client side. By default it is set to true (enabled). |
| AllowDownload | To enable or disable download from the client side. By default it is set to true (enabled). |
| MaxUploadSize | To set the maximum size of the file that can be uploaded in bytes. By default it is set to 2147483648 bytes (2GB) |
| MaxDownloadSize | To set the maximum size of the file that can be downloaded in bytes. By default it is set to 2147483648 bytes (2GB). |
Note:
- For Receiver for HTML5, client side settings can be found under C:\Program Files\Citrix\Receiver Storefront\HTML5Client\configuration.js.
For Receiver for Chrome, download Receiver for Chrome from citrix downloads page, edit configuration.js file and package the app and install under chrome://extensions on Chrome device.
- Following is the behavior in case when the policy is set for upload or download policy in Citrix studio and the client side settings to allow upload or download:
| Citrix Studio Policy
Upload / Download |
Client side setting
Upload / Download |
Resulting Behavior |
| DISABLED | ENABLED | DISABLED |
| DISABLED | DISABLED | DISABLED |
| ENABLED | DISABLED | DISABLED |
| ENABLED | ENABLED | ENABLED |
- In case of conflicts with the registry settings and client side settings for Maximum File Size upload or download, then the minimum size out of the two settings is chosen.
User Experience Recommendation
File Upload:
Users can use the toolbar to upload a file inside a Citrix session. In addition, for a seamless experience of file upload, the admin can set the default location for upload in the UploadFileLocation Registry on the VDA. This enables a simple drag and drop of a file into the session that will upload the file directly to the set location. The users can now easily find the file inside the session in the specified location.
Further, when a user has to attach a file in some web portal then, clicking on attach the server side explorer opens, and if the file is on the client side then the user just need to drag and drop a file in the explorer window. This will make the file available in a default set location for the end user to select.
File Download
Users can download files from the session to their end point devices by either clicking on the download button or performing a “Right-Click and Send-To “ or by performing Save-As functions, as mentioned earlier.
File transfer Logs:
We can get the logs on File Transfer feature in following ways:
- On client browser start logging in the following site:
<storefronturl>/clients/html5client/src/viewlog.html
- On VDA use CDFControl to capture the CDF Traces for the Ica_FT modules.
