Active Storage doesn't have validations yet.
We can restrict the accepted file types in the form:
<div class="field">
<%= f.label :deliverable %>
<%= f.file_field :deliverable, direct_upload: true,
| !!! 5 | |
| html | |
| head | |
| h1 My Site | |
| block scripts | |
| script(src="/jquery.js") | |
| body | |
| block header | |
| header | |
| p some header content |