Create new version of file – Erik Nordin Wahlberg about .NET

With the old VPP file system you could create a new version of a file by right click the file and select Create new version. With the new file system this function has disappeared. You can however update a file by uploading a new file with the same name. A customer to us needed the old method back because of various reasons.

We wanted a quick solution for this feature, so we decided to add a custom template to our GenericMedia-type (inherited from MediaData) where the editor could upload a new version of the file. To accomplish this we needed to go through three steps.

Create a view
Create a Controller with a TemplateDescriptor
Create a UIDescriptor that tells GenericMedia to use OnPageEditView

1. View

First we create a view. We know that this View will get a model of GenericMedia, and that we need a form where we can upload a file. We also add a way to send feedback from the Controller via ViewData.

@model Project.Web.Models.Files.GenericMedia
@{
    Layout = null;
}

<form method="post" enctype="multipart/form-data">
    <h2>Update file</h2>

    <p>To update files metadata, click in the <i>All Properties</i>-button.</p>

    @if (ViewData["message"] != null)
    {
        <h3 style="color: green;">@ViewData["message"].ToString()</h3>
    }

    <input type="file" name="file" />
    <br/><br/>
    <input type="submit" value="Update file" onclick="return confirm('Are you sure you want to update this file?');" />
</form>

@model Project.Web.Models.Files.GenericMedia

Layout = null;

}

<h2>Update file</h2>

<p>To update files metadata, click in the <i>All Properties</i>-button.</p>

@if (ViewData["message"] != null)

{

<h3 style="color: green;">@ViewData["message"].ToString()</h3>

}

</form>

2. Controller with TemplateDescriptor

Now we create a controller to the View. The Controller needs a Index-method where we can pass in a HttpPostedFileBase if this is posted from the View. If this is passed into the method we add some logic to update the file-data of the current content.

We also need to add a TemplateDescriptor-attribute to this controller. In the attribute we define that this controller should be used with RenderingTag.Edit, that it’s a MvcController and where we can find the view.

[TemplateDescriptor(
        Inherited = true,
        AvailableWithoutTag = false,
        Tags = new[] { RenderingTags.Edit },
        TemplateTypeCategory = TemplateTypeCategories.MvcController,
        Path = "/Views/GenericMedia/Index.cshtml"
        )]
    public class GenericMediaController : ActionControllerBase, IRenderTemplate<GenericMedia>
    {
        public ActionResult Index(GenericMedia currentBlock, HttpPostedFileBase file)
        {
            if (file != null)
            {
                var contentRepository = ServiceLocator.Current.GetInstance<IContentRepository>();
                var blobFactory = ServiceLocator.Current.GetInstance<BlobFactory>();

                var media = (GenericMedia)currentBlock.CreateWritableClone();

                media.BinaryData = blobFactory.CreateBlob(media.BinaryDataContainer, Path.GetExtension(file.FileName));
                media.BinaryData.Write(file.InputStream);

                contentRepository.Save(media, SaveAction.Publish);
                ViewData.Add("message", "The file has been updated.");
            }
            return View(currentBlock);
        }
    }

[TemplateDescriptor(

Inherited = true,

AvailableWithoutTag = false,

Tags = new[] { RenderingTags.Edit },

TemplateTypeCategory = TemplateTypeCategories.MvcController,

Path = "/Views/GenericMedia/Index.cshtml"

)]

public class GenericMediaController : ActionControllerBase, IRenderTemplate<GenericMedia>

{

public ActionResult Index(GenericMedia currentBlock, HttpPostedFileBase file)

{

if (file != null)

{

var contentRepository = ServiceLocator.Current.GetInstance<IContentRepository>();

var blobFactory = ServiceLocator.Current.GetInstance<BlobFactory>();

var media = (GenericMedia)currentBlock.CreateWritableClone();

media.BinaryData = blobFactory.CreateBlob(media.BinaryDataContainer, Path.GetExtension(file.FileName));

media.BinaryData.Write(file.InputStream);

contentRepository.Save(media, SaveAction.Publish);

ViewData.Add("message", "The file has been updated.");

}

return View(currentBlock);

}

3. UIDescriptor

Finally we need an UIDescriptor to say that when editing a GenericMedia, we need to see the OnPageEditView. Otherwise we will always see the AllPropertiesView when editing the media. The UIDescriptor is defined by creating a class that inherits from UIDescriptor and with the attribute [UIDescriptorRegistration].

[UIDescriptorRegistration]
    public class GenericMediaUIDescriptor : UIDescriptor<GenericMedia>
    {
        public GenericMediaUIDescriptor()
            : base("icon-document")
        {
            DefaultView = CmsViewNames.OnPageEditView;
            DisabledViews = new string[] { };
        }
    }

[UIDescriptorRegistration]

public class GenericMediaUIDescriptor : UIDescriptor<GenericMedia>

{

public GenericMediaUIDescriptor()

: base("icon-document")

{

DefaultView = CmsViewNames.OnPageEditView;

DisabledViews = new string[] { };

}

At last

If you know a smoother way of doing this, please leave a reply in the comments. 🙂