How to setup basic Rails models associations? - ruby-on-rails

Question

hey guys im working on a application where a devise user sign ups and logs in, Once the user logs in they can 'create a team' or 'join a team'. I have my associations set up like this
user.rb
class User < ApplicationRecord
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :validatable, :confirmable
validates_presence_of :phone, :city, :state, :street, :zip, presence: true, on: :create
belongs_to :team
end
team.rb
class Team < ApplicationRecord
has_many :users
end
and my tables are set up
schema.rb
create_table "teams", force: :cascade do |t|
t.datetime "created_at", null: false
t.datetime "updated_at", null: false
t.string "team_name"
end
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", null: false
t.datetime "updated_at", null: false
t.string "confirmation_token"
t.datetime "confirmed_at"
t.datetime "confirmation_sent_at"
t.string "firstname"
t.integer "team_id"
t.index ["confirmation_token"], name: "index_users_on_confirmation_token", unique: true
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
team_controller.rb
class TeamController < ApplicationController
before_action :authenticate_user!
def index
#team = current_user.team
end
def new_team
end
def create_team
#team = current_user.create_team(sanitize_team)
if #team.save
redirect_to team_root_path
else
render json: #team.errors.full_messages
end
end
def join_team
#teams = Team.all
end
def team
end
private
def sanitize_team
params.require(:team).permit(:team_name, :team_statement)
end
end
I want the users 'team_id' attribute to update with the teams id when they create a team. or when they join a team. Are my associations correct? how would i make this happen in the controller ?

Answer 1

Yes, associations are correct. You can do it better only by adding foreign key to your database schema. It can be done by generator rails g migration AddTeamToUsers team:references
More information about associations can be found here: https://guides.rubyonrails.org/association_basics.html
In controller you have to change only the whitelisting params to allow team_id. And you probably need to add to your form in view something like this:
<%= f.select :team_id, Team.all.map { |t| [t.team_name, t.id] } %>

Answer 2

Let's strip your code example down to the minimum required:
# app/models/team.rb
class Team < ApplicationRecord
has_many :users
end
# app/models/user.rb
class User < ApplicationRecord
belongs_to :team
end
# db/migrate/20181124230131_create_teams.rb
class CreateTeams < ActiveRecord::Migration[5.2]
def change
create_table :teams do |t|
t.string :team_name
t.timestamps
end
end
end
# db/migrate/20181124230136_create_users.rb
class CreateUsers < ActiveRecord::Migration[5.2]
def change
create_table :users do |t|
t.belongs_to :team
t.timestamps
end
end
end
Then in your controller:
team = Team.where(team_name: 'foo').first_or_create!
team.users << current_user

Answer 3

Start by setting the association up as optional:
class User < ApplicationController
belongs_to :team, optional: true
end
Otherwise the validations on the user model will not let the user be saved without a team.
Then setup the teams resource:
# config/routes.rb
resources :teams do
post :join
end
post :join creates an additional POST /teams/:team_id/join route.
Then setup the controller:
class TeamsController
# ...
# GET /teams/new
def new
#team = Team.find
end
# POST /teams
def create
#team = Team.new(team_params)
if #team.save
unless current_user.team
current_user.update(team: #team)
end
redirect_to 'somewhere'
else
render :new
end
end
# ...
def join
#team = Team.find(params[:team_id])
if current_user.update(team: #team)
redirect_to #team, notice: 'Team joined'
else
redirect_to #team, error: 'Could not join team'
end
end
#
private
def team_params
params.require(:team).permit(:team_name, :team_statement)
end
end
Note that prefixing your action names is neither needed nor compatible with the "Rails way". Prefixing column names is also largely superfluous.