Send domain registration email even if load_template_apps fails

[nospame]

Product Description

Theoretically a user could now activate their account without template apps being setup, which would be slightly weird but shouldn't break anything.

Technical Summary

Fixes an issue where a user would not receive their account confirmation email if the task to populate template apps failed, by using a group for the template app tasks, instead of a chord where sending the email relies on the template app tasks. A more involved solution would be to identify and resolve the cause of the template app task's failing, but I'm calling that out of scope here.

Safety Assurance

Doesn't change functionality in any meaningful way, just makes the registration confirmation email not have to wait on a set of template app tasks.

Safety story

Tested on staging to see that registration confirmation emails still work.

Automated test coverage

There is decent automated testing for the registration app generally, but not specifically for sending this email.

QA Plan

Not planning QA.

Rollback instructions

• This PR can be reverted after deploy with no further considerations

Labels & Review

• Risk label is set correctly
• The set of people pinged as reviewers is appropriate for the level of risk of the change

[orangejenny]

which would be slightly weird but shouldn't break anything

Was it not feasible to wait on the tasks and then check the result before emailing? I agree it won't break anything if the user gets the email before the template apps are loaded, but it would be good to minimize weirdness.

[nospame]

which would be slightly weird but shouldn't break anything

Was it not feasible to wait on the tasks and then check the result before emailing? I agree it won't break anything if the user gets the email before the template apps are loaded, but it would be good to minimize weirdness.

@orangejenny My understanding is that's what the chord is trying to do (along with passing any return value into the callback, which is unnecessary here). I don't see that the task gets explicitly retried but in testing I did see that the template apps do eventually get created. Theoretically if the task fails but gets retried and eventually succeeds, the callback should receive the success response, so I'm honestly not sure what's happening there.

[jingcheng16]

Agree identifying and resolving the cause of the template app task's failing out of scope, but I don't think let user register new domain without loading template app is the right fix.
Can you bring it up in the product meeting, or #saas-product channel, let managers decide when to pick it up and apply a proper fix?

[jingcheng16]

I get curious and looked into it yesterday, put up a PR: #35572

[nospame]

Should be unnecessary with retries implemented in #35572