feat(task-queue) Job scheduling with deadline reminder task

[moffatethan]

What this PR does (required):

• Setups Bull
• Runs initializing work on server startup.
• Split job work into process files given to queue initialize in app.js
• Plans out game plan for processing deadline reminders in the process file.

Screenshots / Videos (required):

Any information needed to test this feature (required):

• Setup Redis. On Mac brew install redis is my recommendation.
• Setup environment variables or remove the options from the initializeQueue option which will automatically use localhost.
• Right now, you manually have to add a job to the queue. This would be done via a route.

Notes

I am still planning my approach to adding the cards to the job queue. However, I am thinking adding a route that the front-end can hit that passes down the card id. By doing this, the job processor can lookup the card directly and do it's check for deadlines and process accordingly. Furthermore, I would also create routes for removing a job from the queue (i.e., a card deadline is removed).

Any issues with the current functionality (optional):

• The functionality works, the code isn't as clean as I would like to be as we do not have multiple models and work off of one model that stores POJOs. This code could be cleaned up a lot more if we utilize models for Cards and Columns and making sure a user is attached to a Card we can just fetch all the Cards and filter with Mongoose ODM.

[moffatethan]

The from email usually shouldn't be the same as your personal email but I did this for testing purposes. This should be updated in a configuration file with a verified sender that you setup in your SendGrid.

[moffatethan]

Unfortunately, the way we designed our back-end this isn't the most efficient way of doing this. If we want to make this more efficient we should consider creating Card models as opposed to having everything as a a POJO.

[amahalwy]

I agree; this could be discussed in a future meeting on how to approach our models issue

[amahalwy]

Left some comments but otherwise, looks good to me!

[moffatethan]

Holding off on a merge here because with the plans to refactor this implementation will need to adapt to the changes.