LG-409 Fix 500 errors in production

[stevegsa]

Why: We should properly capture error conditions in our code

How: Rescue known error conditions and translate them into actionable errors and return an appropriate http status code

Hi! Before submitting your PR for review, and/or before merging it, please
go through the following checklist:

• For DB changes, check for missing indexes, check to see if the changes
  affect other apps (such as the dashboard), make sure the DB columns in the
  various environments are properly populated, coordinate with devops, plan
  migrations in separate steps.

• For route changes, make sure GET requests don't change state or result in
  destructive behavior. GET requests should only result in information being
  read, not written.

• For encryption changes, make sure it is compatible with data that was
  encrypted with the old code.

• For secrets changes, make sure to update the S3 secrets bucket with the
  new configs in all environments.

• Do not disable Rubocop or Reek offenses unless you are absolutely sure
  they are false positives. If you're not sure how to fix the offense, please
  ask a teammate.

• When reading data, write tests for nil values, empty strings,
  and invalid formats.

• When calling redirect_to in a controller, use _url, not _path.

• When adding user data to the session, use the user_session helper
  instead of the session helper so the data does not persist beyond the user's
  session.

• When adding a new controller that requires the user to be fully
  authenticated, make sure to add before_action :confirm_two_factor_authenticated.

[jmhooper]

Typically not a fan of comments, but I think the places where we are rescuing here may benefit from a comment explaining the error case it is protecting against since it isn't immediately clear.

[monfresh]

I don't think this is the correct diagnosis of this error. I think we have an incident in production. I see a bunch of legitimate USAJOBS users running into this. Take a look at the Exception Notification logs in our Google group.

[stevegsa]

Yes. I see it. I'll remove this one. I'm surprised it took 4 days to notice.

[stevegsa]

Are you sure raising an encryption error doesn't actually fix the problem?

[jmhooper]

We should probably be guarding against nil in .verify instead.

E.g.

def verify(digest, password)
  return false if password.empty?
  # ...
end

[stevegsa]

Sounds reasonable.

[stevegsa]

I think I'll leave the TypeError rescue in as well.

[jmhooper]

Looks like CodeClimate is made about line length. You may end up needing to move some of the verification logic into a private function somewhere.