Provide string backups for possible empty fields in PD MailJet emails

[TurnerRiley]

The issue of why certain MailJet emails weren't sending was likely that nil fields weren't able to be processed by MailJet, which expects string values. Since I was testing the 3-/10-day reminder and the post-workshop survey emails locally, I always included the test regional partner and test facilitator I created locally out of habit since I knew they wouldn't actually receive emails (since the emails were fake). However, when I tested on production, I didn't use a regional partner or facilitator in the workshops because I didn't want to send real RP's and facilitators test emails, and I believe this caused the rp_name, facilitator_names, etc. variables to be nil rather than empty strings which threw an error in the email.

Production investigation

I was able to confirm this on production and locally when manually triggering send_exit_surveys. When there was an empty field (such as rp_name), MailJet threw an error:

However, once those fields were filled in and I tried again, I saw a success (and an email in my inbox):

Test locally

I created a workshop with the bare minimum fields it would let me create it with to test.

I first confirmed that locally I would see the same error with missing fields:

Then, I added fallback string values for fields that could possibly be nil and tested again (this time, seeing the email):

This PR's changes

This PR adds in the fallback values but still keeps sending the post-workshop survey behind the DCDO flag just to be safe. Once I can confirm that it's working on production as expected, we can do the rollout of the new MailJet email for all users.

Links

Jira ticket: here

Testing story

Local testing.

Follow-up work

Once I confirm this works on production as well, we can start rolling out the new PD MailJet emails.

[drizco]

nice! 🎉