Direct link (no redirect) to files in ActiveStorage

Question

Using url_for() on a file stored in active storage returns a url that leads to the application and then redirects to the actual location. Because of a bug in firefox with CORS, the redirect breaks my application.

Is there any way to get the direct link to the file with ActiveStorage?

Aruwimi

I know you've fixed this using the solution that @jean posted, but have you tried setting up a CORS policy so that you can continue using url_for (or polymorphic_url). At least that way you will be able to keep the path to your assets hidden from public, which can have all sorts of benefits. – Bombardier

@Bombardier CORS is set up properly but the old version of the CORS spec said don't follow redirects and firefox hasn't changed it yet. – Aruwimi

that's strange because I'm seeing no CORS related problems with firefox at all. Perhaps they've quietly fixed it. Running the latest, on Ubuntu 18. Oh well. – Bombardier

Answer 1

You can do this

record.active_storage_object.blob.service.url

Found here https://github.com/rails/rails/blob/main/activestorage/app/models/active_storage/blob.rb#L213

Taka

yeah, that seems to be a more direct way of the method I found. – Aruwimi

Your link returns a 404: github.com/rails/rails/blob/master/activestorage/app/… – Rior

Thanks, method and link has been fixed! – Taka

Answer 2

I had to dig through the rails source to create this so I have no idea how recommended it is but this works for disk storage at least.

ActiveStorage::Current.host = "yourhostname"
attachment_blob = ActiveStorage::Attachment.find_by(record_type: "YourModel", record_id: record.id).blob
direct_url = ActiveStorage::Blob.service.url(
    attachment_blob.key,
    expires_in: 20000,
    disposition: "attachment",
    filename: attachment_blob.filename,
    content_type: attachment_blob.content_type
)

Aruwimi

Answer 3

In Rails 7 blob.service_url doesn't work anymore, it's simply url now.

So: record.active_storage_object.url

Opportunism

Answer 4

For me, rails_blob_url(@blog.pdf) (if you're trying to get the file stored as @blog.pdf) worked best.

Mulvey

This gives you the redirect url – Opportunism