Rails ActiveStorage 变体 url

Question

I'm trying to create an api to get a model's original image and other variants. Right now I'm not storing attachments on external storage, but I plan to save them on S3 in future.

Now I'm asking which is the best way to get images url?

If using url_for the result is: /rails/active_storage/blobs/redirect/... or /rails/active_storage/representations/redirect/... for variants,

while processed.url is returning /rails/active_storage/disk/...

_model.jbuilder

json.image url_for(model.image)
json.image_thumbnail url_for(model.image.variant(:thumbnail).processed)
json.image_icon model.image.variant(:icon).processed.url

Answer 1

I suggest rather than getting the stored URL to use activeStorage's proxy url and does not issue a redirect.

This allows the storage provider to change and ideally you'd cache this response with a CDN like CloudFront if you're on AWS:

json.image_thumbnail rails_storage_proxy_path(model.image.variant(:thumbnail))

More on that here: https://blog.saeloun.com/2021/06/22/rails-active-storage-proxy.html and also in the guides: https://edgeguides.rubyonrails.org/active_storage_overview.html#proxy-mode