In emails exchanges - Allow redirection of Applicants from REMS to GDI User Portal

[brunopacheco1]

Is your feature request related to a problem? Please describe.
When integrating GDI User Portal with REMS, we decided to make REMS only visible in the back-office, by the DAC members, so we enable infrastructure teams to apply extra security measures - e.g. REMS behind firewall.

That means then that any kind of interaction between Applicant and the system is via User Portal only. However, the emails sent by REMS are pointing out to REMS directly, breaking the first principle.

Describe the solution you'd like
Allow operators to configure REMS email template, in an way that is flexible enough to redirect applicants to the User Portal, or the front-office.

Describe alternatives you've considered
There are two options:

• Implement template engines for emails - such as Thymeleaf, FreeMarker. And document what are the variables available.
• Make the URL string patern configurable - e.g. FRONT_OFFICE_URL_PATTERN="https://portal.dev.gdi.lu/applications/%s"

Additional context
The first option is more robust and enables other features, like content formatting.

[meericsc]

Thanks for providing a good description. We discussed this internally, and one possible solution would be to introduce a separate configuration option in config.edn where you could specify:

• url for applying users (applicant/member): used when generating the "invite member" email and the link to the application.
• url for handling users (handler, reviewer, decider): used in emails intended for handling users.

Could you clarify what the specific need was for the separate templates?
Currently, emails can be customized via the translation files, for example:
https://github.com/CSCfi/rems/blob/master/resources/translations/en.edn#L553