Reminder notifications

[nzeager]

Pull Request Template

1. Targeted Issue

Ticket #93 15/60 min notifications BE: Adding backend functionality to send users 15 and 60 minute notifications before a session begins.

2. Overview of Solution

We used Redis, Celery, and Celery Beat to check every 5 minutes if we are within 10-15 or 55-60 minutes of a session. If so we call the appropriate function we set up in models.py to email mentors and mentees to remind them how soon their session is starting. celery.py uses Celery Beat to say we want to run this check every 5 minutes. tasks.py uses Celery and checks if the session is in the appropriate time range.

3. Tools Used

We used Redis, Celery, and Celery Beat.

4. Testing Strategy

Run the local server, Redis, Celery, and Celery Beat (see README for instructions on how to do that) and set up sessions on my local server. Then check to see if the emails are sent at the appropriate times.

5. Future Implications

We'll want to add testing to the code we added in model.py down the line (added TODO comments).

6. Screenshots

n/a

7. Code Reviewers

@GitLukeW @esparr @jeromecox This was a team effort, thanks for everyone's contributions!

[GitLukeW]

Looks like it has a conflict in the pipfile. We will need to get that fixed before merging.

[nzeager]

Need to merge some updates from the main branch. Please hold off on reviewing until noted.

UPDATE: Now ready for review.

[esparr]

Let's look into how to automate the production versus development environments for celery. Here is the Render documentation for Celery: https://render.com/docs/deploy-celery

[esparr]

Looks great! Excited about getting this implemented. I added a few comments and approved.

[GitLukeW]

Thank you!