Right now this is configured using the `secrets.yml` file, which is the
file we've used in the past to configure SMTP settings.
Note that, in the `current_secrets` method, the `if default?` condition
is there so in single-tenant applications it returns the exact same
object as `Rails.application.secrets`, and it makes it immediately clear
for developers reading the code. We're also caching the tenant secrets
(using `||=`) so they behave the same way as Rails secrets; for this to
work properly 100% of the time (for example, in tests) we need to expire
these cached secrets whenever the Rails secrets change.
A similar `unless Tenant.default?` condition is present in the
ApplicationMailer because there's a chance some CONSUL installations
might not be using secrets to define the SMTP settings(they might be
using environment variables, for example) and so in this case we don't
want to force settings based on the secrets.yml file because it would
break the application.
The structure of the SMTP settings in the secrets file should be:
```
production:
tenants:
name_of_the_tenant_subdomain:
smtp_settings:
address:
(...)
```
We modified the link that previously redirected us to the "My content"
page to redirect us to the new page for managing subscriptions.
We also adapted the existing generic text by adding a description of
the related notification.
The `commentable_url` method wasn't updated when we added legislation
proposals.
Back when we first created this method, we couldn't pass budget
investments or topics directly to `polymorphic_url` because they are
nested resources. That isn't the case since commit ff93f5a59, so now we
can simplify this method.
We're keeping the `commentable_url` method for now in order to keep
compatibility with custom changes that might use it, although this
method isn't consistent with the `commentable_path` method (which
receives a comment, and not a commentable), and so we might have to
revisit this code in the future.
We're reading the value from the database, but the
`ApplicationMailer.default` method is evaluated when the application is
started. So if we don't use a Proc, we'll need to restart the server
every time we change the value in the database, or else the old value
will still be used.
Using a Proc makes sure the mailer from address is evaluated at runtime,
so emails are sent using the from address currently defined in the
database.
The same situation took place using the devise mailer. Now we don't need
to check for the settings table being present because the Proc in the
devise initializer won't be evaluated before the settings table is
created and populated.
