Lapsed Donor Logic

[aaronashby]

Overview

Eventually, we want our backend to have the ability to identify donors who haven't donated in a while. We can then use this information to send them emails reminding them to donate to FCC. The goal of this ticket is to implement the former half of this functionality.

Tasks

• Add findLapsedDonors method to DonationsRepository: This method should use a QueryBuilder to efficiently identify unique donor emails.
• Create a new GET endpoint in the donations controller donations/lapsed
• In the service: Create a getLapsedDonors method that the controller will call. This method should act as the orchestrator, invoking the Repository to fetch the data and applying any final business logic or DTO mapping.
• Write unit tests that ensure the following:
  • The list returned should include donors who haven't donated in numMonths months
  • The list returned should include unique donors to prevent sending emails to the same person more than once
  • Only include donations that successfully went through (status === DonationStatus.SUCCEEDED)
  • If a donor has an active recurring donation (i.e. at least one of a given donor's donations satisfies donationType === DonationType.RECURRING), that donor wouldn't be considered lapsed, and thus shouldn't appear in the returned list

Acceptance Criteria

• All unit tests should pass
• Controller route should have effective Swagger documentation