ActiveStorage is not compatible with relative_root_urls

[taa-lze]

Bug

If you have configured a relative root url, the active storage service will redirect wrong.
Example:

http://localhost:3000/anything/rails/active_storage/blobs/blob_hash/image.jpg
Will get redirected to:
http://localhost:3000/rails/active_storage/disk/blob_hash/image.jpg
Instead of:
http://localhost:3000/anything/rails/active_storage/disk/blob_hash/image.jpg

Steps to reproduce

Add to config:
config.relative_url_root = '/anything'
In your view:
image_tag(record.image)

System configuration

Rails version: 6.1.0

Ruby version: ruby 2.7.1p83

[taa-lze]

Workaround:

def direct_file_url(attachment)
    ActiveStorage::Current.host = request.base_url
    ActiveStorage::Blob.service.url(attachment.key, disposition: 'inline', content_type: attachment.content_type, filename: attachment.filename, expires_in: 20_000)
                       .sub!(request.base_url, "#{request.base_url}#{Rails.application.config.relative_url_root}")
end

[abeidahmed]

This is still prevalent in rails 7.1.0.alpha and is not just related to active storage. It also redirects to the wrong URL for JS and CSS if I override the config.

Started GET "/anything/assets/application-5b98c5413b25e84aff009af9d2ca59257596e92d67359343c32a2a3514453b29.css" for 127.0.0.1 at 2021-12-11 12:02:54 +0530
Started GET "/anything/assets/es-module-shims.min-5bee6b190e63d2c7cb18661d714ede9c7ab8ce0b4b3e5cc34092e05ef6046ebd.js" for 127.0.0.1 at 2021-12-11 12:02:54 +0530

ActionController::RoutingError (No route matches [GET] "/anything/assets/es-module-shims.min-5bee6b190e63d2c7cb18661d714ede9c7ab8ce0b4b3e5cc34092e05ef6046ebd.js"):


ActionController::RoutingError (No route matches [GET] "/anything/assets/application-5b98c5413b25e84aff009af9d2ca59257596e92d67359343c32a2a3514453b29.css"):

Started GET "/anything/assets/image-3b62fb9bcec45d4a137737f821fb5db5c6f42b7d1dd01ffb3ba6a066bda87cc8.jpg" for 127.0.0.1 at 2021-12-11 12:02:54 +0530

ActionController::RoutingError (No route matches [GET] "/anything/assets/image-3b62fb9bcec45d4a137737f821fb5db5c6f42b7d1dd01ffb3ba6a066bda87cc8.jpg"):

As defined here, it uses the ENV["RAILS_RELATIVE_URL_ROOT"] to set the relative_url_root. So I think you need to do the same instead of overriding it in the config. You can also check this guide.