Prevent null or duplicate phrase identifiers for projects being inserted into the database

Gemfile

@@ -16,6 +16,8 @@ gem 'turbo-rails'
 
 group :development, :test do
   gem 'dotenv-rails'
+  gem 'factory_bot_rails'
+  gem 'faker'
   gem 'rspec-rails'
   gem 'rubocop'
 end

Gemfile.lock

@@ -72,6 +72,13 @@ GEM
       dotenv (= 2.7.6)
       railties (>= 3.2)
     erubi (1.10.0)
+    factory_bot (6.2.0)
+      activesupport (>= 5.0.0)
+    factory_bot_rails (6.2.0)
+      factory_bot (~> 6.2.0)
+      railties (>= 5.0.0)
+    faker (2.19.0)
+      i18n (>= 1.6, < 2)
     globalid (1.0.0)
       activesupport (>= 5.0)
     i18n (1.8.11)
@@ -96,6 +103,8 @@ GEM
     nokogiri (1.12.5)
       mini_portile2 (~> 2.6.1)
       racc (~> 1.4)
+    nokogiri (1.12.5-x86_64-linux)
+      racc (~> 1.4)
     parallel (1.21.0)
     parser (3.0.3.2)
       ast (~> 2.4.1)
@@ -197,6 +206,8 @@ PLATFORMS
 DEPENDENCIES
   bootsnap
   dotenv-rails
+  factory_bot_rails
+  faker
   importmap-rails
   jbuilder
   pg (~> 1.1)

app/models/project.rb

@@ -1,3 +1,15 @@
+require 'phrase_identifier'
+
 class Project < ApplicationRecord
+  before_validation :check_unique_not_null, on: :create
+  validates :identifier, presence: true, uniqueness: true
   has_many :components, dependent: :destroy
-end
+
+  private
+    def check_unique_not_null
+      self.identifier ||= PhraseIdentifier.generate
+      while !Project.find_by(identifier: self.identifier).nil?
+        self.identifier = PhraseIdentifier.generate
+      end
+    end
+end

db/migrate/20220111141057_make_project_identifier_non_null.rb

@@ -0,0 +1,5 @@
+class MakeProjectIdentifierNonNull < ActiveRecord::Migration[7.0]
+  def change
+    change_column_null(:projects, :identifier, false)
+  end
+end

spec/factories/project.rb

@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+
+FactoryBot.define do
+    factory :project do
+        user_id { rand( 10 ** 10 ) }
+        name { Faker::Book.title }
+        identifier { Faker::Verb.base+'-'+Faker::Verb.base+'-'+Faker::Verb.base }
+        project_type { %w[python, html].sample }
+    end
+end

spec/models/project_spec.rb

@@ -1,7 +1,22 @@
+# frozen_string_literal: true
+
 require 'rails_helper'
 
 RSpec.describe Project, type: :model do
   describe 'associations' do
     it { is_expected.to have_many(:components) }
   end
+
+  describe 'identifier not nil' do
+    subject { FactoryBot.build(:project) }
+    it { is_expected.not_to allow_value(nil).for(:identifier) }
+  end
+
+  describe 'identifier unique' do
+    it do
+      project1 = FactoryBot.create(:project)
+      project2 = FactoryBot.build(:project, identifier: project1.identifier)
+      expect { project2.valid? }.to change { project2.identifier }
+    end
+  end
 end