Extract methods from experience-cs (#87)

This has come out of
https://github.com/RaspberryPiFoundation/experience-cs/issues/546.

This adds two new optional model concerns which provide the following
methods (see individual commits for details):
- [Add
RpiAuth::Models::Roles#parsed_roles](60367e1)
- [Add
RpiAuth::Models::AccountTypes#student_account?](176ecfe)

I've also made a small improvement to the model concern specs and fixed
some rubocop violations.

I've tested the changes in
https://github.com/RaspberryPiFoundation/experience-cs/pull/687.

Author: floehopper

.rubocop_todo.yml

@@ -1,20 +1,20 @@
 # This configuration was generated by
 # `rubocop --auto-gen-config`
-# on 2024-07-02 19:48:59 UTC using RuboCop version 1.64.1.
+# on 2025-06-04 10:53:17 UTC using RuboCop version 1.75.2.
 # The point is for the user to remove these configuration records
 # one by one as the offenses are removed from the code base.
 # Note that changes in the inspected code, or installation of new
 # versions of RuboCop, may require this file to be generated again.
 
-# Offense count: 11
+# Offense count: 12
 # Configuration parameters: EnforcedStyle, AllowedGems, Include.
 # SupportedStyles: Gemfile, gems.rb, gemspec
 # Include: **/*.gemspec, **/Gemfile, **/gems.rb
 Gemspec/DevelopmentDependencies:
   Exclude:
-    - "rpi_auth.gemspec"
+    - 'rpi_auth.gemspec'
 
-# Offense count: 1
+# Offense count: 2
 # Configuration parameters: AllowedMethods, AllowedPatterns, CountRepeatedAttributes.
 Metrics/AbcSize:
   Max: 23
@@ -28,20 +28,12 @@ RSpec/ExampleLength:
 RSpec/MultipleExpectations:
   Max: 4
 
-# Offense count: 8
+# Offense count: 9
 # Configuration parameters: AllowSubject.
 RSpec/MultipleMemoizedHelpers:
   Max: 6
 
-# Offense count: 10
+# Offense count: 13
 # Configuration parameters: AllowedGroups.
 RSpec/NestedGroups:
   Max: 5
-
-# Offense count: 1
-# Configuration parameters: Include, CustomTransform, IgnoreMethods, IgnoreMetadata.
-# Include: **/*_spec.rb
-RSpec/SpecFilePathFormat:
-  Exclude:
-    - "spec/rpi_auth/models/authenticatable_spec.rb"
-    - "spec/rpi_auth/models/with_tokens_spec.rb"

lib/rpi_auth.rb

@@ -5,6 +5,8 @@
 require 'rpi_auth/configuration'
 require 'rpi_auth/models/authenticatable'
 require 'rpi_auth/models/with_tokens'
+require 'rpi_auth/models/roles'
+require 'rpi_auth/models/account_types'
 require 'omniauth/rails_csrf_protection'
 
 module RpiAuth

lib/rpi_auth/models/account_types.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+module RpiAuth
+  module Models
+    module AccountTypes
+      STUDENT_PREFIX = 'student:'
+
+      extend ActiveSupport::Concern
+
+      include Authenticatable
+
+      def student_account?
+        user_id =~ /^#{STUDENT_PREFIX}/o
+      end
+    end
+  end
+end

lib/rpi_auth/models/roles.rb

@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+module RpiAuth
+  module Models
+    module Roles
+      extend ActiveSupport::Concern
+
+      include Authenticatable
+
+      def parsed_roles
+        roles&.split(',')&.map(&:strip) || []
+      end
+    end
+  end
+end

spec/rpi_auth/models/account_types_spec.rb

@@ -0,0 +1,32 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe RpiAuth::Models::AccountTypes, type: :model do
+  subject(:user) { user_class.new(user_id:) }
+
+  let(:user_class) do
+    Class.new(User) do
+      include RpiAuth::Models::Authenticatable
+      include RpiAuth::Models::AccountTypes
+    end
+  end
+
+  describe '#student_account?' do
+    context "when user_id has the 'student:' prefix" do
+      let(:user_id) { RpiAuth::Models::AccountTypes::STUDENT_PREFIX + SecureRandom.uuid }
+
+      it 'returns truthy' do
+        expect(user).to be_student_account
+      end
+    end
+
+    context "when user_id does not have the 'student:' prefix" do
+      let(:user_id) { SecureRandom.uuid }
+
+      it 'returns falsey' do
+        expect(user).not_to be_student_account
+      end
+    end
+  end
+end

spec/rpi_auth/models/authenticatable_spec.rb

@@ -2,12 +2,14 @@
 
 require 'spec_helper'
 
-class DummyUser
-  include RpiAuth::Models::Authenticatable
-end
+RSpec.describe RpiAuth::Models::Authenticatable, type: :model do
+  subject { user_class.new }
 
-RSpec.describe DummyUser, type: :model do
-  subject { described_class.new }
+  let(:user_class) do
+    Class.new(User) do
+      include RpiAuth::Models::Authenticatable
+    end
+  end
 
   it { is_expected.to respond_to(:user_id) }
   it { is_expected.to respond_to(:country) }
@@ -22,11 +24,11 @@ class DummyUser
   it { is_expected.not_to respond_to(:from_omniauth) }
 
   describe 'PROFILE_KEYS' do
-    it { expect(described_class::PROFILE_KEYS).to be_an(Array) }
+    it { expect(user_class::PROFILE_KEYS).to be_an(Array) }
   end
 
   describe '#from_omniauth' do
-    subject(:omniauth_user) { described_class.from_omniauth(auth) }
+    subject(:omniauth_user) { user_class.from_omniauth(auth) }
 
     let(:info) do
       {
@@ -53,7 +55,7 @@ class DummyUser
     end
 
     it 'returns a user with the correct attributes' do
-      expect(omniauth_user).to be_a described_class
+      expect(omniauth_user).to be_a user_class
       expect(omniauth_user).to have_attributes(user_id: 'testuserid', name: 'Bodkin Van Horn',
                                                nickname: 'Hoos-Foos', email: '[email protected]',
                                                country: 'Zimbabwe', country_code: 'ZW',
@@ -64,13 +66,13 @@ class DummyUser
     context 'with unusual keys in info' do
       let(:info) { { foo: :bar, flibble: :woo } }
 
-      it { is_expected.to be_a described_class }
+      it { is_expected.to be_a user_class }
     end
 
     context 'with no info' do
       let(:info) { nil }
 
-      it { is_expected.to be_a described_class }
+      it { is_expected.to be_a user_class }
     end
 
     context 'with no auth set' do

spec/rpi_auth/models/roles_spec.rb

@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe RpiAuth::Models::Roles, type: :model do
+  subject(:user) { user_class.new(roles:) }
+
+  let(:user_class) do
+    Class.new(User) do
+      include RpiAuth::Models::Authenticatable
+      include RpiAuth::Models::Roles
+    end
+  end
+
+  describe '#parsed_roles' do
+    context 'when roles is set to comma-separated string' do
+      let(:roles) { 'role-1,role-2' }
+
+      it 'returns array of role names' do
+        expect(user.parsed_roles).to eq(%w[role-1 role-2])
+      end
+    end
+
+    context 'when roles names have leading & trailing spaces' do
+      let(:roles) { ' role-1 , role-2 ' }
+
+      it 'strips the spaces' do
+        expect(user.parsed_roles).to eq(%w[role-1 role-2])
+      end
+    end
+
+    context 'when roles is set to empty string' do
+      let(:roles) { '' }
+
+      it 'returns empty array' do
+        expect(user.parsed_roles).to eq([])
+      end
+    end
+
+    context 'when roles is set to nil' do
+      let(:roles) { nil }
+
+      it 'returns empty array when roles is set to nil' do
+        expect(user.parsed_roles).to eq([])
+      end
+    end
+  end
+end

spec/rpi_auth/models/with_tokens_spec.rb

@@ -2,15 +2,17 @@
 
 require 'spec_helper'
 
-class DummyUser
-  include RpiAuth::Models::Authenticatable
-  include RpiAuth::Models::WithTokens
-end
-
-RSpec.describe DummyUser, type: :model do
+RSpec.describe RpiAuth::Models::WithTokens, type: :model do
   include ActiveSupport::Testing::TimeHelpers
 
-  subject(:user) { described_class.new }
+  subject(:user) { user_class.new }
+
+  let(:user_class) do
+    Class.new(User) do
+      include RpiAuth::Models::Authenticatable
+      include RpiAuth::Models::WithTokens
+    end
+  end
 
   it { is_expected.to respond_to(:access_token) }
   it { is_expected.to respond_to(:refresh_token) }
@@ -33,9 +35,9 @@ class DummyUser
   end
 
   describe '#from_omniauth' do
-    subject(:user) { described_class.from_omniauth(auth) }
+    subject(:user) { user_class.from_omniauth(auth) }
 
-    let(:omniauth_user) { described_class.new }
+    let(:omniauth_user) { user_class.new }
     let(:info) { omniauth_user.serializable_hash }
     let(:credentials) { { token: SecureRandom.base64(12), refresh_token: SecureRandom.base64(12), expires_in: rand(60..240) } }
 
@@ -52,7 +54,7 @@ class DummyUser
       )
     end
 
-    it { is_expected.to be_a described_class }
+    it { is_expected.to be_a user_class }
 
     it 'sets the access_token' do
       expect(user.access_token).to eq credentials[:token]
@@ -79,13 +81,13 @@ class DummyUser
     context 'with unusual keys in info' do
       let(:info) { { foo: :bar, flibble: :woo } }
 
-      it { is_expected.to be_a described_class }
+      it { is_expected.to be_a user_class }
     end
 
     context 'with no info' do
       let(:info) { nil }
 
-      it { is_expected.to be_a described_class }
+      it { is_expected.to be_a user_class }
     end
 
     context 'with no auth set' do