Rails 2 Walkthrough Lecture

Timeline

• 9:00 quick stretch
• 9:02 start lecture - Part I
• 9:55 break
• 10:00 resume lecture - Part II
• 10:55 break
• 11:00 resume lecture - Part III
• 11:30 - 12:00 end lecture

Part I

README.md

• As you're reading through the README, point out how much time people have, and what the ideal timeframe is that they should be spending in total (~40 min to and hour), this is also 'note taking space' where they can write out the FIGVAPOR/CELLL acronym for future reference.
• Creating DB:
  • don't forget to bundle install
  • run bundle exec rspec and see what happens when you don't create the db (might have to run bundle exec rails db:drop to see this error)
    • you end up with an ActiveRecord::NoDatabaseError: FATAL: database "user_goal_app_test" does not exist error
  • after creating db with bundle exec rails db:create run rspec:
    • errors should now say NameError: uninitialized constant ___ for models and controllers
• Migrations:
  • must create migrations using rails g migration Users col_name:datatype ...
  • stress that migration needs to be saved with the command bundle exec rails db:migrate db:test:load
  • what happens if you don't run db:test:load? Your "test" db schema isn't updated to mirror the "development" db schema.
• Resources:
  • !! stress that they should READ THE WHOLE README before writing any code. !!
  • pay close attention b/c the actual exam could use different column names and datatypes
  • keep in mind the boolean datatype also needs a default of false
• User Authentication Tips:
  • just mention that the bcrypt gem is already commented in
• Specs:
  • Models > Controllers > Views > Features
  • demonstrate how to use save_and_open_page inside of capybara specs later
  • follow the order
• Submission:
  • after renaming the directory, please remove the tmp and vendor folders before submitting, if you have any submission issues, please raise a question on zoom immediately

Migrations and Models

• when running rspec, without making migrations:
  • error: NameError: uninitialized constant User
• after making migration but not migrating:
  • error: ActiveRecord:PendingMigrationError: Migrations are pending. To resolve this issue, run: bin/rails db:migrate RAILS_ENV=test
  • error: when you don't run db:test:load you get a migrations are pending error
• after migrating:
  • error: NameError: uninitialized constant User
• create the model:
  • we get all of our failing specs
  • DON'T FORGET TO INHERIT FROM APPLICATIONRECORD
• FIGVAPER acronym:
  • F: find_by_credentials
  • I: is_password?
  • G: generate_session_token
  • V: validations
  • A: after_initialize, attr_reader
  • P: password=
  • E: ensure_session_token
  • R: reset_session_token!
• some bugs you might come across:
  • not setting @password = password
  • don't forget that reset_session_token! is not using ||=
  • User model: make sure you have ensure_session_token and password= and after initialize and attr_reader in order for validation specs to pass

Part II

Controllers

• Application Controller spec is like a free spec BUT:
  • fill it out so you have access to these methods in your UsersController
  • C: current_user
  • E: ensure_logged_in
  • L: login!
  • L: logout!
  • L: logged_in?
• all the other controllers need to inherit from ApplicationController
• if you run the spec without making a controller: (or spelling error)
  • NameError: unititialized constant UsersController
• after making controller:
  • errors could say: ActionController::UrlGenerationError: No route matches {:action=>"new", :controller=>"users"}
  • means you have to make the routes
• even after defining the methods, you'll run into an error:
  • UsersController#new is missing a template for this request format and variant.
• create the views for views/users
  • make sure not to nest views in the layouts
• understanding that you'll need to implement some methods from application controller to pass user controller specs
• having the whole user controller filled out will still fail some specs which are dependent on having a login page
• Error you might run into:
  • @user.save vs @user.save!: if you use save! you'll actually return errors and fail the specs
• for SessionsController, routes need to have resource singular otherwise specs will show:
  • No route matches {:action=>"create", :controller=>"sessions", :user=>{:username=>"jill_bruce", :password=>"abcdef"}}
• errors for sessions_controller:
  • check specs for specific message rather than calling @user.errors.full_messages
  • destroy action: don't forget that we want to have a before_action :ensure_logged_in for the destory action
• errors for goals_controller:
  • if routing is not nested:
    • No route matches "/users/1/goals"
  • for destroy action:
    • make sure to use find_by on current_user.goals

Part III

Views

• add save_and_open_page in the specs for login (doesn't work on windows for some reason)
• users index
  • make sure that erb tags are the correct type for logic vs rendering
  • include debuggers here at anytime if you want to see what variables you have access to
• users/new
  • make sure labels and inputs are nested inside of the form tag
  • if you use the wrong erb tag in a form, it will not recognize the route on submit, double check action in the form opening tag
  • must include <input type="hidden" name="authenticity_token" value="<%= form_authenticity_token %>"> for the exam
• sessions/new
  • if you copy over the users/new form, make sure to remove the @user.username and @user.password
  • include Sign In somehwere on the page
• users/show
  • form action: look it up in routes, make sure that it takes in the argument @user
  • adding a goal: make sure the radio button values are true/false and that there's a label with True and False
  • button name matters
  • make sure your top level key is SINGULAR: goal[] not goals[]
  • delete goal, make sure the goal_url has argument (goal), don't add the form outside of the do block