Fix error messages for custom uploaders

[timkelty]

Description

This PR broke things for custom uploaders (eg Cloud), as data is undefined in that context.

This is because we need to support the ancient blueimp/jQuery-File-Upload events, as well as standard JS events for alternate uploaders.

So, we need account for data being null, as well as event being an object with different props.

To try and clarify this a bit, I added a default null value for data.

@i-just I also used data.files rather than getting it from the FormData like you were, as that seemed more straightforward. If there is a reason not to use that let me know.

Related issues

• [4.x]: Ambiguous error message when uploading multiple files #14003
• get backup filename from failure handler data #14019

[i-just]

Thanks @timkelty!

I tested your solution, and it works like my previous one in terms of plain cms uploads. data.files seems more straightforward, and I can’t think of a reason not to use it.

I guess the same approach should be used in the 3 other places, too, so I pushed changes for the following files:

• elements/Asset.php (lines: 1485-1558) => triggered when you’re editing an individual asset and use the “Replace file” button
• web/assets/cp/AssetSelectInput.js => triggered when you use direct upload in an Assets field (“Upload files” button)
• web/assets/cp/ImageUpload.js => triggered when you upload a photo to a user profile

Any chance you can test this against the cloud?

[timkelty]

@i-just your additions look 💯, but i'll give it a spin in a cloud project to make sure.

[timkelty]

@i-just tested on cloud and looks good!