My Teaching Assistant App

Models

1. There are two kinds of Users (using Single Table Inheritance) -- Student and Teacher
2. Assignment: has_many homework_documents

• Import attributes: deadline

3. HomeworkDocument: belongs_to grader and submitter, both of which are class Student

• Important attributes: grade, created_at, penalty

Main functions:

1. Randomly send out submitted homework to graders

• Console: Assignment.grade_all
• Select all assignment that is not closed and graded, then send out randomly to a pool of graders. The pool of graders are the students who have submitted their homework for that assignment
• Use Heroku scheduler to run Assignment.grade_all every 1 hour

2. Automatically calculate penalty on late submission. Details in app/models/homework_document.rb.

3. Mailer automatically notify students of available grades and pending deadlines

• Using SendGrid on heroku. Current email address: [email protected]

Add-ons:

• Email: SendGrid
• Ping to keep dyno live: NewRelic

Setting up:

Local setup

1. bundle install > bundle update
2. rake db:migrate > rake db:populate (db:populate to populate database with mock data)

Heroku setup

1. heroku create > git push heroku master > heroku rename new-name
2. heroku run rake db:migrate
3. heroku addons:create sendgrid
   • change host in config.action_mailer.default_url_options = { host: "polsci630.herokuapp.com" }
4. heroku addons:create scheduler
   • Scheduling job: https://devcenter.heroku.com/articles/scheduler#scheduling-jobs
   • rake remind_deadline
   • rake assign_grading
5. heroku addons:create newrelic. Settings > Availability Monitoring > Enter URL
6. https://devcenter.heroku.com/articles/paperclip-s3 Add S3 Storage for paperclip upload

$ heroku config:set S3_BUCKET_NAME=your_bucket_name
$ heroku config:set AWS_ACCESS_KEY_ID=your_access_key_id
$ heroku config:set AWS_SECRET_ACCESS_KEY=your_secret_access_key

7. heroku pg:backups schedule DATABASE_URL --at '03:00 America/New_York'
   • heroku pg:backups
   • heroku pg:backups schedule

Site customization

1. Change site title: application_helper.rb > def site_title
2. Late penalty: homework_document.rb > def calculate_penalty

Rails utility

• Student.find_by(name: "Student 1").submitted_homework_documents.map(&:grade)
• heroku logs -t
• Student.all.map(&:name)
• Teacher.where(name: "Sun Choi").first.update_attribute(:type, "Student")
• HomeworkDocument.where("updated_at < ?", Time.now - 1.month)