Create models and perfom validation

Gemfile

@@ -13,6 +13,7 @@ gem 'sprockets-rails'
 gem 'sqlite3', '~> 1.4'
 
 # Use the Puma web server [https://github.com/puma/puma]
+gem 'pg'
 gem 'puma', '~> 5.0'
 
 # Use JavaScript with ESM import maps [https://github.com/rails/importmap-rails]

Gemfile.lock

@@ -127,6 +127,7 @@ GEM
     nio4r (2.5.9)
     nokogiri (1.15.3-x64-mingw-ucrt)
       racc (~> 1.4)
+    pg (1.5.3-x64-mingw-ucrt)
     public_suffix (5.0.3)
     puma (5.6.6)
       nio4r (~> 2.0)
@@ -218,6 +219,7 @@ DEPENDENCIES
   debug
   importmap-rails
   jbuilder
+  pg
   puma (~> 5.0)
   rails (~> 7.0.6)
   selenium-webdriver

app/models/category.rb

@@ -0,0 +1,16 @@
+class Category < ApplicationRecord
+  belongs_to :author, class_name: 'User', foreign_key: 'author_id'
+  has_many :categories_entities, dependent: :destroy
+  has_many :entities, through: :categories_entities
+
+  validates :name, presence: true, length: { minimum: 3, maximum: 60 }
+  validates :icon, presence: true
+
+  def self.default_icon
+    'fas fa-question-circle'
+  end
+
+  def total_amount
+    entities.sum(:amount)
+  end
+end

app/models/category_entity.rb

@@ -0,0 +1,7 @@
+class CategoryEntity < ApplicationRecord
+  belongs_to :category
+  belongs_to :entity
+
+  validates :category_id, presence: true
+  validates :entity_id, presence: true
+end

app/models/entity.rb

@@ -0,0 +1,8 @@
+class Entity < ApplicationRecord
+  belongs_to :author, class_name: 'User', foreign_key: 'author_id'
+  has_many :categories_entities, dependent: :destroy
+  has_many :categories, through: :categories_entities
+
+  validates :name, presence: true, length: { minimum: 3, maximum: 60 }
+  validates :amount, presence: true, numericality: { greater_than: 0 }
+end

app/models/user.rb

@@ -0,0 +1,7 @@
+class User < ApplicationRecord
+  has_many :categories, dependent: :destroy
+  has_many :entities, dependent: :destroy
+
+  validates :name, presence: true
+  validates :name, length: { minimum: 3, maximum: 50 }
+end

config/database.yml

@@ -1,25 +1,86 @@
-# SQLite. Versions 3.8.0 and up are supported.
-#   gem install sqlite3
+# PostgreSQL. Versions 9.3 and up are supported.
 #
-#   Ensure the SQLite 3 gem is defined in your Gemfile
-#   gem "sqlite3"
+# Install the pg driver:
+#   gem install pg
+# On macOS with Homebrew:
+#   gem install pg -- --with-pg-config=/usr/local/bin/pg_config
+# On macOS with MacPorts:
+#   gem install pg -- --with-pg-config=/opt/local/lib/postgresql84/bin/pg_config
+# On Windows:
+#   gem install pg
+#       Choose the win32 build.
+#       Install PostgreSQL and put its /bin directory on your path.
+#
+# Configure Using Gemfile
+# gem "pg"
 #
 default: &default
-  adapter: sqlite3
+  adapter: postgresql
+  encoding: unicode
+  # For details on connection pooling, see Rails configuration guide
+  # https://guides.rubyonrails.org/configuring.html#database-pooling
   pool: <%= ENV.fetch("RAILS_MAX_THREADS") { 5 } %>
-  timeout: 5000
 
 development:
   <<: *default
-  database: db/development.sqlite3
+  database: budget_app_development
+
+  # The specified database role being used to connect to postgres.
+  # To create additional roles in postgres see `$ createuser --help`.
+  # When left blank, postgres will use the default role. This is
+  # the same name as the operating system user running Rails.
+  username: postgres
+
+  # The password associated with the postgres role (username).
+  password: postgres#13579
+
+  # Connect on a TCP socket. Omitted by default since the client uses a
+  # domain socket that doesn't need configuration. Windows does not have
+  # domain sockets, so uncomment these lines.
+  #host: localhost
+
+  # The TCP port the server listens on. Defaults to 5432.
+  # If your server runs on a different port number, change accordingly.
+  #port: 5432
+
+  # Schema search path. The server defaults to $user,public
+  #schema_search_path: myapp,sharedapp,public
+
+  # Minimum log levels, in increasing order:
+  #   debug5, debug4, debug3, debug2, debug1,
+  #   log, notice, warning, error, fatal, and panic
+  # Defaults to warning.
+  #min_messages: notice
 
 # Warning: The database defined as "test" will be erased and
 # re-generated from your development database when you run "rake".
 # Do not set this db to the same as development or production.
 test:
   <<: *default
-  database: db/test.sqlite3
+  database: budget_app_test
+  username: postgres
+  password: postgres#13579
 
+# As with config/credentials.yml, you never want to store sensitive information,
+# like your database password, in your source code. If your source code is
+# ever seen by anyone, they now have access to your database.
+#
+# Instead, provide the password or a full connection URL as an environment
+# variable when you boot the app. For example:
+#
+#   DATABASE_URL="postgres://myuser:mypass@localhost/somedatabase"
+#
+# If the connection URL is provided in the special DATABASE_URL environment
+# variable, Rails will automatically merge its configuration values on top of
+# the values provided in this file. Alternatively, you can specify a connection
+# URL environment variable explicitly:
+#
+#   production:
+#     url: <%= ENV["MY_APP_DATABASE_URL"] %>
+#
+# Read https://guides.rubyonrails.org/configuring.html#configuring-a-database
+# for a full overview on how database connection configuration can be specified.
+#
 production:
-  <<: *default
-  database: db/production.sqlite3
+   <<: *default
+   url: <%= ENV['DATABASE_URL'] %>

db/migrate/20230727190447_create_users.rb

@@ -0,0 +1,9 @@
+class CreateUsers < ActiveRecord::Migration[7.0]
+  def change
+    create_table :users do |t|
+      t.string :name
+
+      t.timestamps
+    end
+  end
+end

db/migrate/20230727191140_create_categories.rb

@@ -0,0 +1,10 @@
+class CreateCategories < ActiveRecord::Migration[7.0]
+  def change
+    create_table :categories do |t|
+      t.string :name
+      t.string :icon
+
+      t.timestamps
+    end
+  end
+end

db/migrate/20230727191201_create_entities.rb

@@ -0,0 +1,10 @@
+class CreateEntities < ActiveRecord::Migration[7.0]
+  def change
+    create_table :entities do |t|
+      t.string :name
+      t.decimal :amount
+
+      t.timestamps
+    end
+  end
+end

db/migrate/20230727200438_create_categories_entities.rb

@@ -0,0 +1,10 @@
+class CreateCategoriesEntities < ActiveRecord::Migration[7.0]
+  def change
+    create_table :categories_entities do |t|
+      t.references :category, null: false, foreign_key: true
+      t.references :entity, null: false, foreign_key: true
+
+      t.timestamps
+    end
+  end
+end

db/migrate/20230727200739_add_authors_referencesto_entities.rb

@@ -0,0 +1,6 @@
+class AddAuthorsReferencestoEntities < ActiveRecord::Migration[7.0]
+  def change
+    add_reference :entities, :author, foreign_key: { to_table: :users } do
+    end
+  end
+end

db/migrate/20230727200842_add_authors_referencesto_categories.rb

@@ -0,0 +1,6 @@
+class AddAuthorsReferencestoCategories < ActiveRecord::Migration[7.0]
+  def change
+    add_reference :categories, :author, foreign_key: { to_table: :users } do
+    end
+  end
+end

test/fixtures/categories.yml

@@ -0,0 +1,30 @@
+# Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
+
+# This model initially had no columns defined. If you add columns to the
+# model remove the "{}" from the fixture names and add the columns immediately
+# below each fixture, per the syntax in the comments below
+#
+category_one:
+  name: Category 1
+  description: Category 1 description
+  user_id: 1
+  entity_id: 1
+  created_at: <%= Time.now %>
+  updated_at: <%= Time.now %>
+
+category_two:
+  name: Category 2
+  description: Category 2 description
+  user_id: 1
+  entity_id: 1
+  created_at: <%= Time.now %>
+  updated_at: <%= Time.now %>
+
+category_three:
+  name: Category 3
+  description: Category 3 description
+  user_id: 2
+  entity_id: 2
+  created_at: <%= Time.now %>
+  updated_at: <%= Time.now %>
+```

test/fixtures/category_entities.yml

@@ -0,0 +1,24 @@
+# Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
+
+# This model initially had no columns defined. If you add columns to the
+# model remove the "{}" from the fixture names and add the columns immediately
+# below each fixture, per the syntax in the comments below
+#
+category_entity_one:
+  category_id: 1
+  entity_id: 1
+  created_at: <%= Time.now %>
+  updated_at: <%= Time.now %>
+
+category_entity_two:
+  category_id: 2
+  entity_id: 1
+  created_at: <%= Time.now %>
+  updated_at: <%= Time.now %>
+
+category_entity_three:
+  category_id: 3
+  entity_id: 2
+  created_at: <%= Time.now %>
+  updated_at: <%= Time.now %>
+```

test/fixtures/entities.yml

@@ -0,0 +1,26 @@
+# Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
+
+# This model initially had no columns defined. If you add columns to the
+# model remove the "{}" from the fixture names and add the columns immediately
+# below each fixture, per the syntax in the comments below
+#
+entity_one:
+  name: Entity 1
+  description: Entity 1 description
+  user_id: 1
+  created_at: <%= Time.now %>
+  updated_at: <%= Time.now %>
+
+entity_two:
+  name: Entity 2
+  description: Entity 2 description
+  user_id: 2
+  created_at: <%= Time.now %>
+  updated_at: <%= Time.now %>
+
+entity_three:
+  name: Entity 3
+  description: Entity 3 description
+  user_id: 2
+  created_at: <%= Time.now %>
+  updated_at: <%= Time.now %>

test/fixtures/users.yml

@@ -0,0 +1,13 @@
+# Read about fixtures at https://api.rubyonrails.org/classes/ActiveRecord/FixtureSet.html
+
+# This model initially had no columns defined. If you add columns to the
+# model remove the "{}" from the fixture names and add the columns immediately
+# below each fixture, per the syntax in the comments below
+#
+user_one:
+  name: User 1
+  email: admin@localhost
+
+user_two:
+  name: User 2
+  email: user@localhost