Issue with setting file name during upload using Dataverse Web API

[CharlesPP]

Hello,

I'm having a major problem with a site in production and I'm looking for advice on how to solve the problem. As of today (no changes made lately), the method I was using to specify file names during uploads has stopped working, causing the file upload to crash. Previously, I used the x-ms-file-name request parameter to set file names when downloading via an API call, as follows:

webapi.safeAjax({
    type: "PUT",
    url: "/_api/cg_commandes([commande_id])/cg_fichierstl?x-ms-file-name=FileName.stl",
    ...
});

However, this approach now results in a 404 (Not Found) error, specifically stating that the x-ms-file-name query parameter is not supported. Removing this parameter allows the request to go through, but then I lose the ability to set the file name, which is crucial for my application's functionality.

In this situation, I'm looking for advice (urgent if possible) on how to specify file names in this situation. Is there a new recommended method for doing this, or a workaround that you are aware of? Any ideas or suggestions would be greatly appreciated!

Thank you in advance for your help,

Charles

[s1m0nj]

We had a similar issue where our upload was failing to this recent change.  A fix would be good,  for now we’re leaving the file name blank which causes an issue with the file extension.

i would log a call with MS.

[PaulLH]

Hi Charles - thanks for posting this. We encountered the same issue today and your observation on how it works without the x-ms-file-name query parameter was invaluable. 

By chance, we had a workflow that processed the file and we previously stored the filename in another field so we could use that. 

[CharlesPP]

Thank you very much @s1m0nj and @PaulLH for this information. I hope Microsoft will fix this very quickly, it's really annoying for us, our customers and for Microsoft's reputation

[GuidoPreite]

Hi @CharlesPP ,

from your syntax I can see that this is about Power Pages, the request for Power Pages is actually using "PUT" instead of "PATCH" (I don't know if they were able to fix this) so my first suggestion is to do a test using "PATCH", if also with PATCH you don't get the correct result, I strongly suggest to open a support ticket to Microsoft asap.

[CharlesPP]

Thank you @GuidoPreite for this suggestion. It's actually used in a Power Pages site. Unfortunately, it didn't work with PATCH.

[CharlesPP · Accepted solution]

Your knight in shining armor has come up with a workaround!

Instead of using the following code :

webapi.safeAjax({
    type: "PUT",
    url: "/_api/cg_commandes([commande_id])/cg_fichierstl?x-ms-file-name=FileName.stl",
    ...
});

You can specify the file name in the following way using beforeSend, which seems to work even with the bug from Microsoft :

webapi.safeAjax({
    type: "PUT",
    url: "/_api/cg_commandes(" + newRecordId + ")/cg_fichierstl",
    contentType: "application/octet-stream",
    processData: false,
    data: buffer,
    beforeSend: function(xhr) {
        xhr.setRequestHeader("x-ms-file-name", "FileName.stl");
    },
    success: function (res, status, xhr) {
        console.log("File attached successfully", "Response:", res);
    },
    error: function (xhr, status, error) {
        console.error("File Attachment Error:", error, "Status:", status, "Response:", xhr.responseText);
    }
});

I hope it works for you too,

Best regards,

Charles

[GuidoPreite]

thanks @CharlesPP for your code, you are right as that one is a correct header according to the documentation.

https://learn.microsoft.com/en-us/power-apps/developer/data-platform/file-column-data?tabs=webapi#up...

To be honest I don't recall why I am using (and where I found) the ?x-ms-file-name= syntax inside my tool Dataverse REST Builder, I will need to update it to use the header.
Probably also setting the piece as

	headers: {
		"x-ms-file-name": "FileName.stl"
	},

instead of beforeSend should work but if beforeSend works for you better to keep in that way.