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Monthly Archives: October 2013

Resolve Media Library Items Linked in Sitecore Aliases

Tonight I was doing research on extending the aliases feature in Sitecore, and discovered media library items linked in them are not served correctly “out of the box”:

pizza-alias-no-workie

As an enhancement, I wrote the following HttpRequestProcessor subclass to be used in the httpRequestBegin pipeline:

using Sitecore.Configuration;
using Sitecore.Data;
using Sitecore.Data.Items;
using Sitecore.Diagnostics;
using Sitecore.Pipelines.HttpRequest;
using Sitecore.Resources.Media;
using Sitecore.Web;

namespace Sitecore.Sandbox.Pipelines.HttpRequest
{
    public class MediaAliasResolver : HttpRequestProcessor
    {
        public override void Process(HttpRequestArgs args)
        {
            Assert.ArgumentNotNull(args, "args");
            if (!CanProcessAliases())
            {
                return;
            }

            string mediaUrl = GetMediaAliasTargetUrl(args);
            if (string.IsNullOrWhiteSpace(mediaUrl))
            {
                return;
            }

            Context.Page.FilePath = mediaUrl;
        }

        private static bool CanProcessAliases()
        {
            return Settings.AliasesActive && Context.Database != null;
        }

        private static string GetMediaAliasTargetUrl(HttpRequestArgs args)
        {
            Assert.ArgumentNotNull(args, "args");
            ID targetID = Context.Database.Aliases.GetTargetID(args.LocalPath);
            if (targetID.IsNull)
            {
                return string.Empty;
            }

            Item targetItem = args.GetItem(targetID);
            if (targetItem == null || !IsMediaItem(targetItem))
            {
                return string.Empty;
            }

            return GetAbsoluteMediaUrl(targetItem);
        }

        private static bool IsMediaItem(Item item)
        {
            Assert.ArgumentNotNull(item, "item");
            return item.Paths.IsMediaItem && item.TemplateID != TemplateIDs.MediaFolder;
        }

        private static string GetAbsoluteMediaUrl(MediaItem mediaItem)
        {
            string relativeUrl = MediaManager.GetMediaUrl(mediaItem);
            return WebUtil.GetFullUrl(relativeUrl);
        }
    }
}

The HttpRequestProcessor subclass above — after ascertaining the aliases feature is turned on, and the item linked in the requested alias is a media library item — gets the absolute URL for the media library item, and sets it on the FilePath property of the Sitecore.Context.Page instance — this is exactly how the “out of the box” Sitecore.Pipelines.HttpRequest.AliasResolver handles external URLs — and passes along the HttpRequestArgs instance.

I then wedged the HttpRequestProcessor subclass above into the httpRequestBegin pipeline directly before the Sitecore.Pipelines.HttpRequest.AliasResolver:

<?xml version="1.0" encoding="utf-8"?>
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/">
  <sitecore>
    <pipelines>
      <httpRequestBegin>
        <processor patch:before="processor[@type='Sitecore.Pipelines.HttpRequest.AliasResolver, Sitecore.Kernel']"
                   type="Sitecore.Sandbox.Pipelines.HttpRequest.MediaAliasResolver, Sitecore.Sandbox" />
      </httpRequestBegin>
    </pipelines>
  </sitecore>
</configuration>

Let’s take this for a spin.

I had already defined the following alias in Sitecore beforehand — the error page at the top of this post is evidence of that:

pizza-alias

After navigating to http://sandbox/pizza — the URL to the pizza alias in my local Sitecore sandbox instance (don’t click on this link because it won’t go anywhere unless you have a website named sandbox running on your local machine) — I was brought to the media library image on the front-end:

media-alias-pizza-redirected

If you have any recommendations on improving this, or further thoughts on using aliases in Sitecore, please share in a comment below.

Until next time, have a pizzalicious day!

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Insert a New Item After a Sibling Item in Sitecore

Have you ever thought to yourself “wouldn’t it be nice to insert a new item in the Sitecore content tree at a specific place among its siblings without having to move the inserted item up or down multiple times to position it correctly?”

I’ve had this thought more than once, and decided to put something together to achieve this.

The following class consists of methods to be used in pipeline processors of the uiAddFromTemplate pipeline to make this happen:

using System.Collections.Generic;
using System.Linq;

using Sitecore.Configuration;
using Sitecore.Globalization;
using Sitecore.Data;
using Sitecore.Data.Items;
using Sitecore.Diagnostics;
using Sitecore.Shell.Applications.Dialogs.ItemLister;
using Sitecore.Shell.Framework;
using Sitecore.Web.UI.Sheer;

namespace Sitecore.Sandbox.Shell.Framework.Pipelines.AddFromTemplate
{
    public class InsertAfterItemOperations
    {
        private string SelectButtonText { get; set; }

        private string ModalIcon { get; set; }

        private string ModalTitle { get; set; }

        private string ModalInstructions { get; set; }

        public void StoreTemplateResult(ClientPipelineArgs args)
        {
            args.Parameters["Template"] = args.Result;
        }

        public void EnsureParentAndChildren(ClientPipelineArgs args)
        {
            AssertArguments(args);
            Item parent = GetParentItem(args);
            EnsureParentItem(parent, args);
            args.Parameters["HasChildren"] = parent.HasChildren.ToString();
            args.IsPostBack = false;
        }

        public void GetInsertAfterId(ClientPipelineArgs args)
        {
            AssertArguments(args);
            bool hasChildren = false;
            bool.TryParse(args.Parameters["HasChildren"], out hasChildren);
            if (!hasChildren)
            {
                SetCanAddItemFromTemplate(args);
                return;
            }

            Item parent = GetParentItem(args);
            EnsureParentItem(parent, args);
            if (!args.IsPostBack)
            {
                ItemListerOptions itemListerOptions = new ItemListerOptions
                {
                    ButtonText = SelectButtonText,
                    Icon = ModalIcon,
                    Title = ModalTitle,
                    Text = ModalInstructions,
                    Items = parent.Children.ToList()
                };

                SheerResponse.ShowModalDialog(itemListerOptions.ToUrlString().ToString(), true);
                args.WaitForPostBack();
            }
            else if (args.HasResult)
            {
                args.Parameters["InsertAfterId"] = args.Result;
                SetCanAddItemFromTemplate(args);
                args.IsPostBack = false;
            }
            else
            {
                SetCanAddItemFromTemplate(args);
                args.IsPostBack = false;
            }
        }

        private void SetCanAddItemFromTemplate(ClientPipelineArgs args)
        {
            Assert.ArgumentNotNull(args, "args");
            args.Parameters["CanAddItemFromTemplate"] = bool.TrueString;
        }

        private static Item GetParentItem(ClientPipelineArgs args)
        {
            AssertArguments(args);
            Assert.ArgumentNotNullOrEmpty(args.Parameters["id"], "id");
            return GetItem(GetDatabase(args.Parameters["database"]), args.Parameters["id"], args.Parameters["language"]);
        }

        private static void EnsureParentItem(Item parent, ClientPipelineArgs args)
        {
            if (parent != null)
            {
                return;
            }

            SheerResponse.Alert("Parent item could not be located -- perhaps it was deleted.");
            args.AbortPipeline();
        }

        public void AddItemFromTemplate(ClientPipelineArgs args)
        {
            Assert.ArgumentNotNull(args, "args");
            bool canAddItemFromTemplate = false;
            bool.TryParse(args.Parameters["CanAddItemFromTemplate"], out canAddItemFromTemplate);
            if (canAddItemFromTemplate)
            {
                int index = args.Parameters["Template"].IndexOf(',');
                Assert.IsTrue(index >= 0, "Invalid return value from dialog");
                string path = StringUtil.Left(args.Parameters["Template"], index);
                string name = StringUtil.Mid(args.Parameters["Template"], index + 1);
                Database database = GetDatabase(args.Parameters["database"]);
                Item parent = GetItem(database, args.Parameters["id"], args.Parameters["language"]);
                if (parent == null)
                {
                    SheerResponse.Alert("Parent item not found.");
                    args.AbortPipeline();
                    return;
                }

                if (!parent.Access.CanCreate())
                {
                    SheerResponse.Alert("You do not have permission to create items here.");
                    args.AbortPipeline();
                    return;
                }

                Item item = database.GetItem(path);
                if (item == null)
                {
                    SheerResponse.Alert("Item not found.");
                    args.AbortPipeline();
                    return;
                }
                
                History.Template = item.ID.ToString();
                Item added = null;
                if (item.TemplateID == TemplateIDs.Template)
                {
                    Log.Audit(this, "Add from template: {0}", new string[] { AuditFormatter.FormatItem(item) });
                    TemplateItem template = item;
                    added = Context.Workflow.AddItem(name, template, parent);
                }
                else
                {
                    Log.Audit(this, "Add from branch: {0}", new string[] { AuditFormatter.FormatItem(item) });
                    BranchItem branch = item;
                    added = Context.Workflow.AddItem(name, branch, parent);
                }

                if (added == null)
                {
                    SheerResponse.Alert("Something went terribly wrong when adding the item.");
                    args.AbortPipeline();
                    return;
                }

                args.Parameters["AddedId"] = added.ID.ToString();
            }
        }

        public void MoveAdded(ClientPipelineArgs args)
        {
            AssertArguments(args);
            Assert.ArgumentNotNullOrEmpty(args.Parameters["AddedId"], "AddedId");
            Item added = GetAddedItem(args);
            if (string.IsNullOrWhiteSpace(args.Parameters["InsertAfterId"]))
            {
                Items.MoveFirst(new [] { added });
            }
            
            SetSortorder(GetItemOrdering(added, args.Parameters["InsertAfterId"]));
        }

        private static void AssertArguments(ClientPipelineArgs args)
        {
            Assert.ArgumentNotNull(args, "args");
            Assert.ArgumentNotNull(args.Parameters, "args.Parameters");
            Assert.ArgumentNotNullOrEmpty(args.Parameters["database"], "database");
            Assert.ArgumentNotNullOrEmpty(args.Parameters["language"], "language");
        }

        private static Item GetAddedItem(ClientPipelineArgs args)
        {
            AssertArguments(args);
            Assert.ArgumentNotNullOrEmpty(args.Parameters["AddedId"], "AddedId");
            return GetItem(GetDatabase(args.Parameters["database"]), args.Parameters["AddedId"], args.Parameters["language"]);
        }

        private static Item GetItem(Database database, string id, string language)
        {
            Assert.ArgumentNotNull(database, "database");
            Assert.ArgumentNotNullOrEmpty(id, "id");
            Assert.ArgumentNotNullOrEmpty(language, "language");
            return database.Items[id, Language.Parse(language)];
        }

        private static Database GetDatabase(string databaseName)
        {
            Assert.ArgumentNotNullOrEmpty(databaseName, "databaseName");
            return Factory.GetDatabase(databaseName);
        }

        private static IList<Item> GetItemOrdering(Item added, string insertAfterId)
        {
            IList<Item> ordering = new List<Item>();
            foreach (Item child in added.Parent.GetChildren())
            {
                ordering.Add(child);
                bool shouldAddAfter = string.Equals(child.ID.ToString(), insertAfterId);
                if (shouldAddAfter)
                {
                    ordering.Add(added);
                }
            }

            return ordering;
        }

        private static void SetSortorder(IList<Item> items)
        {
            Assert.ArgumentNotNull(items, "items");
            for (int i = 0; i < items.Count; i++)
            {
                int sortorder = (i + 1) * 100;
                SetSortorder(items[i], sortorder);
            }
        }

        private static void SetSortorder(Item item, int sortorder)
        {
            Assert.ArgumentNotNull(item, "item");
            if (item.Access.CanWrite() && !item.Appearance.ReadOnly)
            {
                item.Editing.BeginEdit();
                item[FieldIDs.Sortorder] = sortorder.ToString();
                item.Editing.EndEdit();
            }
        }
    }
}

In the StoreTemplateResult method, we store the ID of the template selected in the ‘Insert from Template’ dialog. This dialog is launched by clicking the ‘Insert from Template’ menu option in the item context menu — an example of this can be seen in my test run near the bottom of this post.

The EnsureParentAndChildren method makes certain the parent item exists — we want to be sure another user did not delete it in another Sitecore session — and ascertains if the parent item has children.

Logic in the GetInsertAfterId method launches another dialog when the parent item does have children. This dialog prompts the user to select a sibling item to precede the new item. If the ‘Cancel’ button is clicked, the item will be inserted before all sibling items.

The AddItemFromTemplate method basically contains the same logic that can be found in the Execute method in the Sitecore.Shell.Framework.Pipelines.AddFromTemplate class in Sitecore.Kernel.dll, albeit with a few minor changes — I removed some of the nested if/else conditionals, and stored the ID of the newly created item, which is needed when reordering the sibling items (this is how we move the new item after the selected sibling item).

The MoveAdded method is where we reorder the siblings items with the newly created item so that the new item follows the selected sibling. If there is no selected sibling, we just move the new item to the first position.

I then put all of the above together using the following patch configuration file:

<?xml version="1.0" encoding="utf-8"?>
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/">
  <sitecore>
    <processors>
      <uiAddFromTemplate>
        <processor mode="on" patch:after="processor[@type='Sitecore.Shell.Framework.Pipelines.AddFromTemplate,Sitecore.Kernel' and @method='GetTemplate']"
                   type="Sitecore.Sandbox.Shell.Framework.Pipelines.AddFromTemplate.InsertAfterItemOperations, Sitecore.Sandbox" method="StoreTemplateResult"/>
        <processor mode="on" patch:after="processor[@type='Sitecore.Sandbox.Shell.Framework.Pipelines.AddFromTemplate.InsertAfterItemOperations, Sitecore.Sandbox' and @method='StoreTemplateResult']"
                   type="Sitecore.Sandbox.Shell.Framework.Pipelines.AddFromTemplate.InsertAfterItemOperations, Sitecore.Sandbox" method="EnsureParentAndChildren"/>
        <processor mode="on" patch:after="processor[@type='Sitecore.Sandbox.Shell.Framework.Pipelines.AddFromTemplate.InsertAfterItemOperations, Sitecore.Sandbox' and @method='EnsureParentAndChildren']"
                   type="Sitecore.Sandbox.Shell.Framework.Pipelines.AddFromTemplate.InsertAfterItemOperations, Sitecore.Sandbox" method="GetInsertAfterId">
          <SelectButtonText>Insert After</SelectButtonText>
          <ModalIcon>Applications/32x32/nav_up_right_blue.png</ModalIcon>
          <ModalTitle>Select Item to Insert After</ModalTitle>
          <ModalInstructions>Select the item you would like to insert after. If you would like to insert before the first item, just click 'Cancel'.</ModalInstructions>
        </processor>
        <processor mode="on" patch:instead="processor[@type='Sitecore.Shell.Framework.Pipelines.AddFromTemplate,Sitecore.Kernel' and @method='Execute']"
                   type="Sitecore.Sandbox.Shell.Framework.Pipelines.AddFromTemplate.InsertAfterItemOperations, Sitecore.Sandbox" method="AddItemFromTemplate" />
        <processor mode="on" patch:after="processor[@type='Sitecore.Sandbox.Shell.Framework.Pipelines.AddFromTemplate.InsertAfterItemOperations, Sitecore.Sandbox' and @method='AddItemFromTemplate']"
                   type="Sitecore.Sandbox.Shell.Framework.Pipelines.AddFromTemplate.InsertAfterItemOperations, Sitecore.Sandbox" method="MoveAdded" />
      </uiAddFromTemplate> 
    </processors>
  </sitecore>
</configuration>

Let’s test this out.

This is how my content tree looked before adding new items:

no-new-items

I right-clicked on my Home item to launch its context menu, and clicked ‘Insert from Template’:

item-context-menu-insert-from-template

I was presented with the “out of the box” ‘Insert from Template’ dialog, and selected a template:

insert-from-template-dialog

Next I was prompted to select a sibling item to insert the new item after:

selected-insert-after

As you can see the new item now resides after the selected sibling:

was-inserted-after

If you have any thoughts on this, or other ideas around modifying the uiAddFromTemplate pipeline, please share in a comment below.

Specify the Maximum Width of Images Uploaded to the Sitecore Media Library

Last week someone started a thread in one of the SDN forums asking how one could go about making Sitecore resize images larger than a specific width down to that width.

Yesterday an astute SDN visitor recommended using a custom getMediaStream pipeline processor to set the maximum width for images — a property for this maximum width is exposed via the GetMediaStreamPipelineArgs parameters object passed through the getMediaStream pipeline.

I thought I would try out the suggestion, and came up with the following getMediaStream pipeline processor:

using Sitecore.Diagnostics;

using Sitecore.Resources.Media;

namespace Sitecore.Sandbox.Resources.Media
{
    public class MaxWidthProcessor
    {
        public int MaxWidth { get; set; }

        public void Process(GetMediaStreamPipelineArgs args)
        {
            Assert.ArgumentNotNull(args, "args");
            if (!ShouldSetMaxWidth(args))
            {
                return;
            }

            args.Options.MaxWidth = MaxWidth;
        }

        private bool ShouldSetMaxWidth(GetMediaStreamPipelineArgs args)
        {
            Assert.ArgumentNotNull(args, "args");
            return MaxWidth > 0 && args.Options.MaxWidth < 1;
        }
    }
}

I then interlaced it into the getMediaStream pipeline before the ResizeProcessor processor — this is the processor where the magical resizing happens — using the following patch configuration file:

<?xml version="1.0" encoding="utf-8"?>
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/">
  <sitecore>
    <pipelines>
      <getMediaStream>
        <processor patch:before="processor[@type='Sitecore.Resources.Media.ResizeProcessor, Sitecore.Kernel']"
                   type="Sitecore.Sandbox.Resources.Media.MaxWidthProcessor, Sitecore.Sandbox">
          <MaxWidth>1024</MaxWidth>
        </processor>  
      </getMediaStream>
    </pipelines>
  </sitecore>
</configuration>

The maximum width for images is set to 1024 pixels — the width I am using in my test below.

Let’s see how we did.

I decided to use one of my favorite images that ships with Sitecore for testing:

lighthouse-small

As you can see its width is much larger than 1024 pixels:

lighthouse-properties

After uploading the lighthouse image into the media library, its width was set to the maximum specified, and its height was scaled down proportionally:

resized-during-upload

If you have any thoughts on this, or other ideas on resizing images uploaded to the media library, please drop a comment.

Specify Which Sitecore Web Forms for Marketers Form To Render Via the Query String

Today I saw a post in one of the SDN forums asking how one could go about building a page in Sitecore that can render a Web Forms for Marketers (WFFM) form based on an ID passed via the query string.

I built the following WFFM FormRenderer as a “proof of concept” to accomplish this — this solution assumes the ID we are passing is the ID of the form, and not some other ID (or guid):

using System;
using System.Web;

using Sitecore.Data.Items;
using Sitecore.Diagnostics;
using Sitecore.Form.Core.Configuration;
using Sitecore.Form.Core.Renderings;

namespace Sitecore.Sandbox.Form.Core.Renderings
{
    public class DetectIDFormRenderer : FormRender
    {
        protected override void OnInit(System.EventArgs e)
        {
            string detectedFormId = GetDetectedFormId();
            if (IsValidFormId(detectedFormId))
            {
                FormID = detectedFormId;
            }
            
            base.OnInit(e);
        }

        private static string GetDetectedFormId()
        {
            return HttpContext.Current.Request["formId"];
        }

        private static bool IsValidFormId(string id)
        {
            return !string.IsNullOrWhiteSpace(id) 
                    && IsID(id) 
                    && IsFormId(id);
        }
        
        private static bool IsID(string id)
        {
            Sitecore.Data.ID sitecoreID;
            return Sitecore.Data.ID.TryParse(id, out sitecoreID);
        }

        private static bool IsFormId(string id)
        {
            Item item = StaticSettings.ContextDatabase.GetItem(id);
            return item != null && item.TemplateID == IDs.FormTemplateID;
        }
    }
}

The FormRenderer above grabs the specified form’s ID via a query string parameter, ascertains whether it’s truly an ID, and determines whether it is an ID of a WFFM Form in Sitecore — these are done via the IsID and IsFormId methods.

If the supplied form ID is valid, we save it to the FormID property defined in the base FormerRender class. Otherwise, we flow through to the “out of the box” logic.

Now it’s time to register the above class in Sitecore.

I duplicated the “out of the box” Form Webcontrol under /sitecore/layout/Renderings/Modules/Web Forms for Marketers, renamed the item to something appropriate, and updated the code-defining fields to point to our new FormRender above:

Detect-ID-Form-FormRenderer

I decided to reuse an existing page item with a WFFM form — I didn’t want to step through ‘Insert Form’ wizard so that I could save time — and swapped out the “out of the box” Form Webcontrol with the new one we created above:

webcontrol-switch

I ensured we had a default form set just in case of query string manipulation, or in the event the form cannot be found by the given ID:

default-form-is-set

I published everything, and navigated to my form page:

no-form-specified

I then specified the empty guid:

invalid-form-specified

I manipulated the query string again, but this time passing a valid form ID:

valid-form-specified

I then changed the form ID again but with another valid form ID:

another-valid-form-specified

If you have any suggestions around making this better, or ideas for a different solution, please drop a comment.

Restrict Certain Types of Files From Being Uploaded in Sitecore

Tonight I was struck by a thought while conducting research for a future blog post: should we prevent users from uploading certain types of files in Sitecore for security purposes?

You might thinking “Prevent users from uploading files? Mike, what on Earth are you talking about?”

What I’m suggesting is we might want to consider restricting certain types of files — specifically executables (these have an extension of .exe) and DOS command files (these have an extension of .com) — from being uploaded into Sitecore, especially when files can be easily downloaded from the media library.

Why should we do this?

Doing this will curtail the probability of viruses being spread among our Sitecore users — such could happen if one user uploads an executable that harbors a virus, and other users of our Sitecore system download that tainted executable, and run it on their machines.

As a “proof of concept”, I built the following uiUpload pipeline processor — the uiUpload pipeline lives in /configuration/sitecore/processors/uiUpload in your Sitecore instance’s Web.config — to restrict certain types of files from being uploaded into Sitecore:

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Web;
using System.Xml;

using Sitecore.Diagnostics;
using Sitecore.Globalization;
using Sitecore.Pipelines.Upload;

namespace Sitecore.Sandbox.Pipelines.Upload
{
    public class CheckForRestrictedFiles : UploadProcessor
    {
        private List<string> _RestrictedExtensions;
        private List<string> RestrictedExtensions
        {
            get
            {
                if (_RestrictedExtensions == null)
                {
                    _RestrictedExtensions = new List<string>();
                }

                return _RestrictedExtensions;
            }
        }

        public void Process(UploadArgs args)
        {
            foreach(string fileKey in args.Files)
            {
                string fileName = GetFileName(args.Files, fileKey);
                string extension = Path.GetExtension(fileName);
                if (IsRestrictedExtension(extension))
                {
                    args.ErrorText = Translate.Text(string.Format("The file \"{0}\" cannot be uploaded. Files with an extension of {1} are not allowed.", fileName, extension));
                    Log.Warn(args.ErrorText, this);
                    args.AbortPipeline();
                }
            }
        }

        private static string GetFileName(HttpFileCollection files, string fileKey)
        {
            Assert.ArgumentNotNull(files, "files");
            Assert.ArgumentNotNullOrEmpty(fileKey, "fileKey");
            return files[fileKey].FileName;
        }

        private bool IsRestrictedExtension(string extension)
        {
            return RestrictedExtensions.Exists(restrictedExtension => string.Equals(restrictedExtension, extension, StringComparison.CurrentCultureIgnoreCase));
        }

        protected virtual void AddRestrictedExtension(XmlNode configNode)
        {
            if (configNode == null || string.IsNullOrWhiteSpace(configNode.InnerText))
            {
                return;
            }

            RestrictedExtensions.Add(configNode.InnerText);
        }
    }
}

The class above ascertains whether each uploaded file has an extension that is restricted — restricted extensions are defined in the configuration file below, and are added to a list of strings via the AddRestrictedExtensions method — and logs an error message when a file possessing a restricted extension is encountered.

I then tied everything together using the following patch configuration file including specifying some file extensions to restrict:

<?xml version="1.0" encoding="utf-8"?>
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/">
  <sitecore>
    <processors>
      <uiUpload>
        <processor mode="on" type="Sitecore.Sandbox.Pipelines.Upload.CheckForRestrictedFiles, Sitecore.Sandbox" patch:before="processor[@type='Sitecore.Pipelines.Upload.CheckSize, Sitecore.Kernel']">
          <restrictedExtensions hint="raw:AddRestrictedExtension">
            <!-- Be sure to prefix with a dot -->
            <extension>.exe</extension>
            <extension>.com</extension>
          </restrictedExtensions>
        </processor>
      </uiUpload>
    </processors>
  </sitecore>
</configuration>

Let’s try this out.

I went to the media library, and attempted to upload an executable:

upload-exe-dialog_001

After clicking the “Open” button, I was presented with the following:

upload-exe-error

An error in my Sitecore instance’s latest log file conveys why I could not upload the chosen file:

upload-exe-error-log

If you have thoughts on this, or have ideas for other processors that should be added to uiUpload pipeline, please share in a comment.