ruby on rails has everything you need- it is organized programming logic patterned as MVC!
UPDATE: MAR 2020
I took a really long hiatus between finishing up the rails project above & jumping in (between year-end holidays, winter break vacation, relocating from NYC to SoCal & allllll of the things that come along with making a cross-country move and establishing new residency, new job, new health networks, etc.), not to mention wedding planning. Whew.
One huge issue I was having when I last left off with using the devise gem is that I don’t fully comprehend all the magic it contains. In trying to get my project to login with new attributes from the get-go or routing to a different page than default, it involves adjusting code that is pre-set and easy to use, but when it breaks, I cannot find where it goes wrong. When logged in and continuing to build out code, everything works that I intended to work… however, upon registration, I cannot determine the source of the break because I lack comprehensive knowledge of the devise tool.
With that said, I’m going to save what I have from this project and jump back into it a different time.
I am going to restart my project without using the devise gem, 1) to do a much needed refresher on my rails knowledge and 2) to intentionally create the login/logout processes from scratch to avoid the issues I’m running into with customization with the devise gem.
So here goes:
I am still creating a social application around movie viewing.
User
A user will be able to register for an account & login with a password.
Any user will be able to create movies, a user can create events for movies, a user can comment on the events for movies, and a user can create reviews for movies.
Movie
A movie can have multiple events, and it can have many reviews.
Review
A review is written by a user for a movie
Comment
A comment is written by user for an event of a movie
Guestlist
A guestlist is the join table between a user who is attending an event and an event.
Aliasing
I have a lot of trouble understanding how to properly alias in rails, but in my model, there are going to be some items that have a dual association so I have to rename the attribute in order to approrpriately pull the correct info.
Each user can create multiple events, aka they can host multiple events. Each user can also attend multiple events, aka they are attendees of multiple events.
Has_many events won’t be enough to differentiate the two, so I have used aliasing.
In this way, my models & migrations are as follows for the specific attributes:
class User < ApplicationRecord
has_many :events, foreign_key: 'host_id'
# event.host will know that host == user and pull the corresponding user object
# foreign_key is referencing what column to look for in the Event table
has_many :guestlists
has_many :events, through: :guestlists, foreign_key: 'attendee_id'
# event.attendee will know that attendee == user and pull the corresponding user object
# foreign_key is referencing what column to look for in the Guestlist table
class Event < ApplicationRecord
belongs_to :host, class_name: "User"
# event.host will pull the host (aka user) who created the event
has_many :guestlists
has_many :attendees, through: :guestlists, foreign_key: "attendee_id"
# event.attendees will pull the attendees (aka users) who are attending the event
# foreign_key is referencing what column to look for in the Guestlist table
end
class Guestlist < ApplicationRecord
belongs_to :event
belongs_to :attendee, class_name: "User"
# user.events will pull events that the attendee (aka user) is attending
end
To create working migrations, I ran into errors when trying to use the belongs_to because there are additional checks rails seems to be doing to ensure referential integrity, so the way to go was to explicity note the foreign keys in my migrations.
There is nothing special with the users able/users migration, because the aliasing has really occurred with its associated objects, i.e. the users table will not need any special columns.
Rather, the affected tables are: Events table, where a user is referenced to as a host - (host_id) Guestlist (join table), where a user is referenced to as an attendee - (attendee_id)
MIGRATION
class CreateEvents < ActiveRecord::Migration[6.0]
def change
create_table :events do |t|
t.belongs_to :movie, null: false, foreign_key: true
t.integer :host_id, null: false
end
end
end
SCHEMA
create_table "events", force: :cascade do |t|
t.bigint "movie_id", null: false
t.integer "host_id", null: false
t.index ["movie_id"], name: "index_events_on_movie_id"
end
MIGRATION
class CreateGuestlists < ActiveRecord::Migration[6.0]
def change
create_table :guestlists do |t|
t.belongs_to :event, null: false, foreign_key: true
t.integer :attendee_id, null: false, foreign_key: true
end
end
end
SCHEMA
create_table "guestlists", force: :cascade do |t|
t.bigint "event_id", null: false
t.integer "attendee_id", null: false
t.index ["event_id"], name: "index_guestlists_on_event_id"
end
Another example of aliasing to use a preferred name for associations related via a join table:
Review belongs_to a movie & belongs_to a user, but let’s call the user a ‘viewer’
Review belongs_to :viewer, class_name: "User", foreign_key: "user_id"
In the Movie model, a movie has_many reviews, but a movie also has_many users/viewers from its reviews.
NOTE: movies do not belongto a user in my project, thus this is a hasmany, through: association.
To let rails know where to look was a series of trial & error for me.
Movie has_many :reviews
Movie has_many :viewers, through: :reviews, source: :viewer, foreign_key: 'user_id'
The following SQL query is returned when you run movie_object.viewers (equivalent of movie_object.users)
SELECT "users".* FROM "users" INNER JOIN "reviews" ON "users"."id" = "reviews"."user_id" WHERE "reviews"."movie_id" = $1 LIMIT $2
In short, what could have been as simple as:
belongs_to :user
Movie
has_many :reviews
has_many :users, through: :reviews
has become
belongs_to :viewer, class_name: "User", foreign_key: "user_id"
Movie
has_many :reviews
has_many :viewers, through: reviews, source: :viewer, foreign_key: "user_id"
so that instead of typing movie_object.users to see all the users who reviewed the movie, I am going to refer to the users as “viewers.” i.e. to see all the users who I know have watched the movie because they have reviewed it, I can run movie_object.viewers. More work on the coding side, but more intuitive on the user side.
Scopes
Reading about scopes, documentation notes that it really just is ‘syntactic sugar’ so when I got confused by its syntax, I just started off writing it as a class method, and then copying & pasting the method body into the scope template.
Additionally, I had to wrap my head around what sql queries I was planning to use.
For example, I want to know which event has the most attendees. Essentially, rails would have to go through each event from Event.all and let me know how many attendees were in each; then it would need to order it by the attendee counts and return the top value.
In my head, it made sense to try to do Event.attendees, and call a count on that… but the class Event does not have attendees… an instance of an event has attendees.
So in reality, I need to do a scope on my JOIN TABLE for Events & Attendees, which is my Guestlist table, whose attributes are attendee_id and event_id.
To get my guest counts, I GROUP the guestlist by :event_id and then call COUNT
class Guestlist < ApplicationRecord
scope :event_guest_counts, -> { self.group(:event_id).count }
The SQL query would look like:
SELECT COUNT(*) AS count_all, "guestlists"."event_id"
AS guestlists_event_id
FROM "guestlists"
GROUP BY "guestlists"."event_id"
=> {1=>1, 2=>5}
It returns me the :event_id and its count in a hash for each event I have. i.e. For event with event_id: 1, I have 1 attendee & for event with event_id: 2, I have 5 attendees
Recall that Guestlist.event_guest_counts => {1=>1, 2=>5} with key:value pairs being :event_id and then its count. My order_events_by_popularity scope is a scope that orders the event_id listings by the attendee counts.
scope :order_events_by_popularity, -> { self.group(:event_id).order("count(*)").count }
To make it easy to call upon, I created a class method to look up the event and pull out that object.
class Guestlist < ApplicationRecord
def self.most_popular_event
event_id = self.order_events_by_popularity.first.first
@event = Event.find_by(id: event_id)
end
end
Nested Resources
In creating a movie review or in posting a comment on an event, a user really only has that action upon seeing a movie or viewing an event.
In other words, when viewing movie reviews, I don’t intend for users to be able to see a page with all the reviews ever written for all the movies in the database; it would always be associated with a movie.
First, I created my nested resources in my routes file.
resources :movies do
resources :reviews
end
To make things very user-friendly, I created a review form on the movie#show page.
views/movie#show
<%= form_with model: @review, url: movie_reviews_path(@movie, @review), class: "review-form" do |f| %>
<%= f.label :review_title %>
<%= f.text_field :review_title><br>
<%= f.label :rating %>
<%= f.select :rating, [1, 2, 3, 4, 5] %><br>
<%= f.text_area :description %>
<center>
<%= f.submit "Add My Review"%>
</center>
<% end %>
```
Note the path for this form is movie_reviews_path(@movie, @review), where @movie is the current movie whose show page we are on which is noted in the movie#show controller, and @review = Review.new.
In the Review controller:
def create @review = Review.new(review_params) @review.movie_id = params[:movie_id] end
def review_params
params.require(:review).permit(:review_title, :rating, :description) end ```
Params sent look like this: <ActionController::Parameters {“authenticity_token”=>”XXX”, “review”=>{“review_title”=>”New Joker Review”, “rating”=>”4”, “description”=>”Great Movie.”}, “commit”=>”Add My Review”, “controller”=>”reviews”, “action”=>”create”, “movie_id”=>”1”} permitted: false>
All the form elements are within the REVIEW hash, while the movie_id param which is taken from the movie_path url (/movies/:id(.:format)) is passed along separately, as a result of having a nested resource.
Using Partials
Bits of copy & pasted code for my views were able to be thrown into a partial.
Per convention, I named the partial in the view folder for which it would be used, preceded by an underscore. When calling upon the view to render, the underscore is omitted. ex: <%= render "event_form" %>
When using partials for the rendering of my nested form, I used the format in which I needed to specify the local variable being passed in because the post path for my URL’s differed, whereas other forms only differed in the @movie object being passed in, etc.
<%= form_with model: @review, url: **new_movie_review_path**(@review.movie), class: "review-form" do |form| %>
<%= render partial: "movie_review_form", locals: { f: form } %>
<% end %>
```
```
<%= form_with model: @review, url: **movie_review_path**(@review), class: "review-form" do |form| %>
<%= render partial: "movie_review_form", locals: { f: form } %>
<% end %>
OmniAuth
I incorporated Google’s Oauth2 into my project, which required that I do a few things.
- Add gems
- gem ‘omniauth-google-oauth2’
-
- This is the omniauth gem that allows for authentication with Google via OAuth2 in OmniAuth
- gem ‘dotenv-rails’
-
- I used this gem to manage my environment configuration variables
-
I created a project on the google developer console to get my credentials and set-up the oauth consent screen, etc. I saved my client_id and client_secret into a .env file AND I made sure to update my .gitignore file to make sure .env was listed on there. This is to ensure my info doesn’t get pushed out.
- Created an omniauth.rb file in my initializers with the following:
Rails.application.config.middleware.use OmniAuth::Builder do provider :google_oauth2, ENV['GOOGLE_CLIENT_ID'], ENV['GOOGLE_CLIENT_SECRET'], { :skip_jwt => true } end - Set-up my google sign-in & callback routes
get '/auth/google_oauth2', to: 'sessions#new' get '/auth/google_oauth2/callback', to:'sessions#oauth_login' - Updated my controller actions incorporate the creation of a new user or sign-in by existing user through omniauth. I created a new method to handle sign-ins by oauth2. The default information returned when not listed as part of a scope in your omniauth.rb is the email and profile. This info is stored in:
request.env['omniauth.auth']so you can pull information from that to build or find your user. For this project, I used the oauth information to find_or_create a new user and ensured that their session was created in the controller action. My sign-out buttons for a normal log-in vs an oauth login would clear the session (and not do anything with the user’s login status with their google account… whether or not they are still logged in.)
Pic-Pal Blog Post
Pre-2020 Project Re-do
For my project, my goal is to create a Rails application that allows for social networking around movie-viewing.
Users should have the capability to create an account, and mark movies as seen if they have seen those movies. For movies that users have seen, they can add their review + rating (0-5 stars).
Users can also create events around movies. These events will have a user as a host, and also have users as attendees. In these events, users can add comments to communicate with other users attending the event.
Movies will have its own attributes, as well as be associated with events and ratings, as well as users through those events & ratings.
Additionally, there are a plethora of helpful gems that have fleshed out capabilities that were recommended for use with our rails gem, including:
gem 'bootstrap-sass', '>= 3.4.1' # styling extension of CSS3
gem 'bootstrap', '~> 4.3.1' # most popular HTML, CSS, and JS framework
gem 'jquery-rails' # javaScript library
gem 'devise' # registration/mailing/login, etc
gem 'cancancan' # user authorizations
gem 'simple_form' # form builder + compatibility with devise
gem 'rspec-rails' # for test building
gem 'omniauth-google-oauth2' # for omniauth with google
The associations for this project were confusing for me, because I was going to have objects that had many of another object, but in two separate ways. I tried to wrap my head around this and read up more about activerecord associations via the odin project.
Mapping out the associations is incredibly helpful for me. It helps me see how the models are related, and prompts me to ask all the appropriate how’s. For example, if a user has_many hosted events, but a user also has_many attended events–how does it know which is which? Which prompts me to go to the events model, where an event belongs to a host, but it doesn’t contain a list of attendees. For that, I’ll need to make a join table that lists the guest + the event so the info can be queried.
It was a bit of trial and error to get all the associations working the way I intended, and even then, I think there may be use of scopes that I’m unfamiliar with that can clean things up a bit. In the end, my models looked like this:
User
has_many :hosted_events, foreign_key: :host_id, class_name: "Event"
has_many :guestlists, foreign_key: :attendee_id
has_many :attended_events, through: :guestlists, source: :event, class_name: "Event"
has_many :movie_reviews, foreign_key: :reviewer_id, class_name: "Review"
has_many :reviewed_movies, through: :movie_reviews, source: :movie, class_name: "Movie"
has_many :to_watches
has_many :movies_in_to_watches, through: :to_watches, source: :movie, class_name: "Movie"
has_many :comments
create_table "users", force: :cascade do |t|
t.string "email", default: "", null: false
t.string "encrypted_password", default: "", null: false
t.string "reset_password_token"
t.datetime "reset_password_sent_at"
t.datetime "remember_created_at"
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
t.string "username"
t.index ["email"], name: "index_users_on_email", unique: true
t.index ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
end
Movie
has_many :reviews, dependent: :destroy
has_many :events, dependent: :destroy
has_many :reviewers, through: :reviews
create_table "movies", force: :cascade do |t|
t.string "name"
t.string "genre"
t.string "image_url"
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
end
Event
belongs_to :host, class_name: "User"
has_many :guestlists, foreign_key: :event_id, dependent: :destroy
has_many :attendees, through: :guestlists, source: :attendee, dependent: :destroy
has_many :comments, dependent: :destroy
belongs_to :movie
validates :host_id, uniqueness: { scope: :datetime, message: "you are already hosting another event at this date/time" }
create_table "events", force: :cascade do |t|
t.string "title"
t.datetime "datetime"
t.bigint "host_id", null: false
t.bigint "movie_id", null: false
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
t.string "location"
t.index ["host_id"], name: "index_events_on_host_id"
t.index ["movie_id"], name: "index_events_on_movie_id"
end
Comment
belongs_to :user
belongs_to :event
create_table "comments", force: :cascade do |t|
t.text "description"
t.bigint "user_id", null: false
t.bigint "event_id", null: false
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
t.index ["event_id"], name: "index_comments_on_event_id"
t.index ["user_id"], name: "index_comments_on_user_id"
end
Guestlist
belongs_to :attendee, class_name: "User"
belongs_to :event
create_table "guestlists", force: :cascade do |t|
t.bigint "attendee_id", null: false
t.bigint "event_id", null: false
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
t.index ["attendee_id"], name: "index_guestlists_on_attendee_id"
t.index ["event_id"], name: "index_guestlists_on_event_id"
end
Review
belongs_to :reviewer, class_name: "User"
belongs_to :movie
validates :rating, numericality: {greater_than_or_equal_to: 0, less_than_or_equal_to: 5}
create_table "reviews", force: :cascade do |t|
t.integer "rating"
t.bigint "reviewer_id", null: false
t.bigint "movie_id", null: false
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
t.string "title"
t.text "description"
t.index ["movie_id"], name: "index_reviews_on_movie_id"
t.index ["reviewer_id"], name: "index_reviews_on_reviewer_id"
end
ToWatch
belongs_to :movie
belongs_to :user
scope :watched, -> { where(watched: true) }
scope :tosee, -> { where(watched: false) }
create_table "to_watches", force: :cascade do |t|
t.boolean "watched"
t.bigint "movie_id", null: false
t.bigint "user_id", null: false
t.datetime "created_at", precision: 6, null: false
t.datetime "updated_at", precision: 6, null: false
t.index ["movie_id"], name: "index_to_watches_on_movie_id"
t.index ["user_id"], name: "index_to_watches_on_user_id"
end
In using devise, a lot of the user sign_up and log_in code are built in with the gem. In order to add a :username field, it was necessary to add the field in as a new migration to add_column. I updated the registration form in users/registration/new to include the :username field so that it would take up the field as a param. However, I was unable to figure out how to properly have the registration include the username.
I found a functioning workaround through updating routes.
devise_for :users, controllers: { registrations: 'users/registrations', omniauth_callbacks: 'users/omniauth_callbacks' }
registrations allowed for it to specify the controller being used for sign_up, and the omniauth_callbacks is for use with omniauth.
Then, I updated the sanitized params in the registrations controller to permit :username and added a @user.update into the user#create method in devise/registration to take in the :username.
There are a few specific views I want a user to be able to view, including:
- events#index
- movies#index
- user#show = dashboard; to prevent users from viewing other users’ dashboards, instead of pulling from the params[:id], it is really calling upon the current_user method to pull data
Additionally, I’ve used control flow in the views to only allow users to edit events if they are the host of the event, and to only show delete buttons to remove themselves from attending events. Users are also not allowed to post reviewed unless they indicate that they have seent the movies.
The dependency: :destroy added to the various models ensure that if an event is deleted, all its related events and reviews are also deleted. Ideally, I also intended for users to be able to comment on events that they are attending, but if they choose to no longer attend, upon deleting themselves from the guestlist, all their comments on the events page will also be deleted. However, since the guestlist is a pure join_table, I’m unsure how the dependency works here, so I have a functional workaround in the guestlists_controller to check through and destory all comments by the user on the event on which they are no longer attending.
Using scopes on the ToWatch model was a very useful tool to quickly tease out the watched: true’s vs the watched: false’s I am using it in the users#show controller to count up the movies that the user has marked as want to see vs has seen to provide a little blurb on the user’s movie stats.
Routes
root to: "movies#home"
# root GET / movies#home
#necessary when using devise
resources :guestlists
# guestlists GET /guestlists(.:format) guestlists#index
# POST /guestlists(.:format) guestlists#create
# new_guestlist GET /guestlists/new(.:format) guestlists#new
# edit_guestlist GET /guestlists/:id/edit(.:format) guestlists#edit
# guestlist GET /guestlists/:id(.:format) guestlists#show
# PATCH /guestlists/:id(.:format) guestlists#update
# PUT /guestlists/:id(.:format) guestlists#update
# DELETE /guestlists/:id(.:format) guestlists#destroy
resources :comments
# comments GET /comments(.:format) comments#index
# POST /comments(.:format) comments#create
# new_comment GET /comments/new(.:format) comments#new
# edit_comment GET /comments/:id/edit(.:format) comments#edit
# comment GET /comments/:id(.:format) comments#show
# PATCH /comments/:id(.:format) comments#update
# PUT /comments/:id(.:format) comments#update
# DELETE /comments/:id(.:format) comments#destroy
resources :events
# events GET /events(.:format) events#index
# edit_event GET /events/:id/edit(.:format) events#edit
# event GET /events/:id(.:format) events#show
# PATCH /events/:id(.:format) events#update
# PUT /events/:id(.:format) events#update
# DELETE /events/:id(.:format) events#destroy
resources :movies
# movies GET /movies(.:format) movies#index
# POST /movies(.:format) movies#create
# new_movie GET /movies/new(.:format) movies#new
# edit_movie GET /movies/:id/edit(.:format) movies#edit
# movie GET /movies/:id(.:format) movies#show
# PATCH /movies/:id(.:format) movies#update
# PUT /movies/:id(.:format) movies#update
# DELETE /movies/:id(.:format) movies#destroy
resources :reviews
# reviews GET /reviews(.:format) reviews#index
# POST /reviews(.:format) reviews#create
# new_review GET /reviews/new(.:format) reviews#new
# edit_review GET /reviews/:id/edit(.:format) reviews#edit
# review GET /reviews/:id(.:format) reviews#show
# PATCH /reviews/:id(.:format) reviews#update
# PUT /reviews/:id(.:format) reviews#update
# DELETE /reviews/:id(.:format) reviews#destroy
resources :to_watches, only: [:create, :update]
# to_watches POST /to_watches(.:format) to_watches#create
# to_watch PATCH /to_watches/:id(.:format) to_watches#update
# PUT /to_watches/:id(.:format) to_watches#update
resources :users, only: [:show]
# user GET /users/:id(.:format) users#show
resources :users, only: [:show] do
resources :events, only: [:show]
end
# user_event GET /users/:user_id/events/:id(.:format) events#show
# GET /users/:id(.:format) users#show
resources :users, only: [:show] do
resources :reviews, only: [:show]
end
# user_review GET /users/:user_id/reviews/:id(.:format) reviews#show
# GET /users/:id(.:format) users#show
resources :users, only: [:show] do
resources :to_watches, only: [:show]
end
# user_to_watch GET /users/:user_id/to_watches/:id(.:format) to_watches#show
# GET /users/:id(.:format) users#show
resources :movies, only: [:show] do
resources :reviews, only: [:new]
end
# new_movie_review GET /movies/:movie_id/reviews/new(.:format) reviews#new
# GET /movies/:id(.:format) movies#show
resources :movies, only: [:show] do
resources :events, only: [:new]
end
# new_movie_event GET /movies/:movie_id/events/new(.:format) events#new
# GET /movies/:id(.:format) movies#show
devise_for :users, controllers: { registrations: 'users/registrations', omniauth_callbacks: 'users/omniauth_callbacks' }
# new_user_session GET /users/sign_in(.:format) devise/sessions#new
# user_session POST /users/sign_in(.:format) devise/sessions#create
# destroy_user_session DELETE /users/sign_out(.:format) devise/sessions#destroy
# user_google_oauth2_omniauth_authorize GET|POST /users/auth/google_oauth2(.:format) users/omniauth_callbacks#passthru
# user_google_oauth2_omniauth_callback GET|POST /users/auth/google_oauth2/callback(.:format) users/omniauth_callbacks#google_oauth2
# new_user_password GET /users/password/new(.:format) devise/passwords#new
# edit_user_password GET /users/password/edit(.:format) devise/passwords#edit
# user_password PATCH /users/password(.:format) devise/passwords#update
# PUT /users/password(.:format) devise/passwords#update
# POST /users/password(.:format) devise/passwords#create
# cancel_user_registration GET /users/cancel(.:format) devise/registrations#cancel
# new_user_registration GET /users/sign_up(.:format) devise/registrations#new
# edit_user_registration GET /users/edit(.:format) devise/registrations#edit
# user_registration PATCH /users(.:format) devise/registrations#update
# PUT /users(.:format) devise/registrations#update
# DELETE /users(.:format) devise/registrations#destroy
# POST /users(.:format) devise/registrations#create
As seen, devise has a lot of built-in routes (and there are more as well with mailers, etc not shown here. The updates I made included adding the :users scope. NOTE: need to update config/initializers/devise.rb file to allow the following:
config.scoped_views = true
config.default_scope = :user
There are still a few things I am working to build out, including the user dashboard & routing + add a search bar/filtering tool to be able to highlight specific events that the user can specify e.g. events for specific movies, events that are in the future vs events that have already occurred. ~ circa Dec 2019