Rails Access data from a different Model within a Controller - ruby-on-rails

Question

UPDATE: Problem solved, thanks to Sebastian and Gabriel for the helpful pointers.
The relevant changes to my code are as follows:
app/controllers/pomodoro_cycles_controller.rb
def pomodoro_collections
{
pomodoro_collection_0: Pomodoro.offset(0).first(100),
pomodoro_collection_1: Pomodoro.offset(100).first(100)
}
end
app/views/pomodoro_cycles/show.html.erb
<% #pomodoros_collections.each do |pomodoros_collection_hash| %>
<h2><%= pomodoros_collection_hash[0] %></h2>
<% pomodoros_collection_hash[1].each do |pomodoro| %>
<p>
<%= pomodoro.id %>
<%= pomodoro.color %>
</p>
<% end %>
<% end %>
NOTA BENE:
The #first method in ActiveRecord returns an Array, so the keys in my original Hash were nested Arrays. Instead, the following was sufficient to return an Array of Pomodoro objects:
Pomodoro.offset(0).first(100)
DESCRIPTION OF ORIGINAL PROBLEM
Rails 5, PostgreSQL
PROBLEM: I cannot access Pomodoro.all from within PomodoroCycleController
I have two scaffolds: Pomodoro and PomodoroCycle, and I want to access the full list of Pomodoros within the PomdoroCycle controller.
The following code is kept simple, in order to make as clear as possible what I'm trying to do. If I can do these things, then I'll be able to do much more, but one step at a time.
Regarding the db migration files, I have already run bundle exec rails db:migrate
I want to display a full list of Pomodoros in the PomodoroCycle Show View (later to be displayed in Index), but I don't know what is missing.
From app/controllers/pomodoro_cycles_controller.rb
def show
#pomodoros_collections = pomodoro_collections
end
def pomodoro_collections
{
pomodoro_collection_0 => [Pomodoro.offset(0).first(100)],
pomodoro_collection_1 => [Pomodoro.offset(100).first(100)]
}
end
From app/views/pomodoro_cycles/show.html.erb
<% #pomodoros_collections.each do |collection| %>
<p><%= collection %></p>
<% end %>
However, this displays nothing in the browser.
app/models/pomodoro_cycle.rb
class PomodoroCycle < ApplicationRecord
has_many :pomodoros
end
app/models/pomodoro.rb
class Pomodoro < ApplicationRecord
belongs_to :pomodoro_cycle
end
Updated db/migrate/20180103032759_create_pomodoro_cycles.rb:
class CreatePomodoroCycles < ActiveRecord::Migration[5.1]
def change
create_table :pomodoro_cycles do |t|
t.string :activity
t.integer :iteration
t.integer :matrix_side_length
t.datetime :created_at
t.datetime :completed_at
t.string :category_labels, array:true, default: []
t.string :category_colors, array:true, default: []
t.string :username
t.timestamps
end
create table :pomodoros do |t|
t.belongs_to :pomodoro_cycle, index: true
t.datetime :completed_at
t.timestamps
end
add_index :pomodoros, :pomodoro_cycle_id
end
end
Untouched db/migrate/20180103054425_create_pomodoros.rb
class CreatePomodoros < ActiveRecord::Migration[5.1]
def change
create_table :pomodoros do |t|
t.boolean :status
t.string :category
t.string :color
t.datetime :completed_at
t.string :username
t.timestamps
end
end
end

Answer 1

First of all, as #SebastianPalma pointed out in the comments, the syntax is wrong
def pomodoro_collections
{
pomodoro_collection_0 => [Pomodoro.offset(0).first(100)],
pomodoro_collection_1 => [Pomodoro.offset(100).first(100)]
}
end
should be:
def pomodoro_collections
{
pomodoro_collection_0: [Pomodoro.offset(0).first(100)],
pomodoro_collection_1: [Pomodoro.offset(100).first(100)]
}
end
Make the keys in the hash symbols
Then to display each Pomodoro put something like:
<% #pomodoros_collections.each do |pomodoros_collection_hash| %>
<h2><%= pomodoros_collection_hash[0] %></h2>
<% pomodoros_collection_hash[1].each do |pomodoro| %>
<p><%= pomodoro.id %></p> #Or the attribute you want to display
<% end %>
<% end %>
Hope this help