Since we're going to remove Paperclip and Active Storage doesn't provide
any validations, we have to either write our own validation rules or use
a different gem.
We're using the file_validators gem instead of the
`active_storage_validations` gem because the latter doesn't support
proc/lambda objects in size and content type definitions. We need to use
them because in our case these values depend on settings stored in the
database.
Just like we did with regular attachments, we're moving the logic to
generate URLs out of the model.
Note we're changing the `image_path_for` helper method in order to
return a `polymorphic_path` because sometimes it's used in combination
with `favicon_link_tag`, and `favicon_link_tag` doesn't automatically
generate a polymorphic URL when given an `ActiveStorage::Attachment`
record.
In order to migrate existing files from Paperclip to ActiveStorage, we
need Paperclip to find out the files associated to existing database
records. So we can't simply replace Paperclip with ActiveStorage.
That's why it's usually recommended [1] to first run the migration and
then replace Paperclip with ActiveStorage using two consecutive
deployments.
However, in our case we can't rely on two consecutive deployments
because we have to make an easy process so existing CONSUL installations
don't run into any issues. We can't just release version 1.4.0 and 1.5.0
and day and ask everyone to upgrade twice on the same day.
Instead, we're following a different plan:
* We're going to provide a Rake task (which will require Paperclip) to
migrate existing files
* We still use Paperclip to generate link and image tags
* New files are handled using both Paperclip and ActiveStorage; that
way, when we make the switch, we won't have to migrate them, and in
the meantime they'll be accessible thanks to Paperclip
* After we make the switch, we'll update the `name` column in the active
storage attachments tables in order to remove the `storage_` prefix
Regarding our handling of new files, the exception are cached
attachments. Since those attachments are temporary files used while
submitting a form and we have to delete them afterwards, we're only
handling them with Paperclip. We'll handle these ones in version 1.5.0.
Note the task creating the dev seeds was failing after these changes
with an `ActiveStorage::IntegrityError` exception because we were
opening some files without closing them. If the same file was attached
twice, it failed the second time.
We're solving it by closing the files with `File.open` and a block. Even
though we didn't get any errors, we're doing the same thing in the
`Attachable` concern because it's a good practice to close files after
we're done with them.
Also note we have to change the CKEditor Active Storage code so it's
compatible with Paperclip. In this case, I haven't been able to write a
test to confirm the attachment exists; I was getting the same
`ActiveStorage::IntegrityError` mentioned above.
Finally, we're updating the site customization image controller to use
`update` so the image and the attachment are updated within the same
transaction. This is also what we do in most controllers.
[1] https://www.youtube.com/watch?v=tZ_WNUytO9o
Instead of adding the padding to each individual element inside the
container, why not adding padding to the container itself? The answer is
"because we want the background of the children elements to take the
width of the whole screen". But this generates either HTML cluttered
with elements to add padding or repetitive padding definitions in the
CSS.
So now we only define the padding once, and when an element requires a
full width background or border, we use the `full-width-background`
mixin.
In this case the code is a bit more complex because the header is also
used in the dashboard and admin layouts:
* In the public layout, the body has a margin, so we include the mixin
to take margin into account
* In the dashboard layout, the header itself has a margin, so we include
the same mixin
* In the admin layout, the headet doesn't have a margin but gets the
whole width, so in this case we include the mixin which dosen't take
the margin into account
In the future, the idea is to apply this principle to the <body>
element and remove the `@include grid-column-gutter` in the CSS as well
as the `small-12 column` classes in the HTML.
Note we use the `calc()` function inside the mixin instead of using it
in the `$full-width-margin` variable. That way we avoid nested `calc()`
operations, which don't work in Internet Explorer.
Also note we're using `flex-grow: 1` to make one element appear on the
left of the screen and the other one on the right. It would be easier to
use `justify-content: space-between` (which is actually the default for
the top-bar element). However, there's a bug in Internet Explorer and
old versions of Firefox; they include the absolutely-positioned
`::before` element we use to set the full width background when
calculating where to position the elements. The bug was fixed in Firefox
52 (released in 2017).
Finally, we're removing the padding from our logo. In order to allow
logos like the new one and at the same time provide backwards
compatibility to logos in existing CONSUL installations, we're relaxing
the validation rule for the logo width.
We were very inconsistent regarding these rules.
Personally I prefer no empty lines around blocks, clases, etc... as
recommended by the Ruby style guide [1], and they're the default values
in rubocop, so those are the settings I'm applying.
The exception is the `private` access modifier, since we were leaving
empty lines around it most of the time. That's the default rubocop rule
as well. Personally I don't have a strong preference about this one.
[1] https://rubystyle.guide/#empty-lines-around-bodies
