From 1633caccbad2327543c411d931335786930ed670 Mon Sep 17 00:00:00 2001
From: FinnIckler <finnickler@gmail.com>
Date: Wed, 31 May 2023 19:28:40 +0200
Subject: [PATCH] Add Rubocop and run Linters on Test Action (#56)

Add Rubocup and Eslint runs on test
---
 .github/workflows/test.yml                    |  13 +
 .rubocop.yml                                  | 227 ++++++++++++++++++
 Frontend/src/index.jsx                        |   2 +-
 .../register/components/RegistrationPanel.jsx |   2 +-
 Gemfile                                       |  30 +--
 Rakefile                                      |   4 +-
 app/channels/application_cable/channel.rb     |   2 +
 app/channels/application_cable/connection.rb  |   2 +
 app/controllers/application_controller.rb     |   2 +
 app/controllers/healthcheck_controller.rb     |   4 +-
 app/controllers/metrics_controller.rb         |  14 +-
 app/controllers/registration_controller.rb    | 130 +++++-----
 app/helpers/competition_api.rb                |   3 +-
 app/helpers/competitor_api.rb                 |   3 +-
 app/jobs/application_job.rb                   |   2 +
 app/mailers/application_mailer.rb             |   6 +-
 app/models/application_record.rb              |   2 +
 app/worker/queue_poller.rb                    |  14 +-
 app/worker/registration_processor.rb          |  38 +--
 bin/bundle                                    |  46 ++--
 bin/rails                                     |   8 +-
 bin/rake                                      |   6 +-
 bin/setup                                     |  18 +-
 config.ru                                     |   4 +-
 config/application.rb                         |   6 +-
 config/boot.rb                                |   8 +-
 config/environment.rb                         |   4 +-
 config/environments/development.rb            |   9 +-
 config/environments/production.rb             |  20 +-
 config/environments/test.rb                   |   8 +-
 config/initializers/_vault.rb                 |  27 +--
 config/initializers/aws.rb                    |   7 +-
 config/initializers/cors.rb                   |  14 +-
 .../initializers/filter_parameter_logging.rb  |   6 +-
 config/initializers/inflections.rb            |   1 +
 config/puma.rb                                |  14 +-
 config/routes.rb                              |   2 +
 db/seeds.rb                                   |  22 +-
 .../application_cable/connection_test.rb      |  22 +-
 .../healthcheck_controller_test.rb            |   4 +-
 .../registration_controller_test.rb           |   3 +-
 test/test_helper.rb                           |  22 +-
 42 files changed, 545 insertions(+), 236 deletions(-)
 create mode 100644 .rubocop.yml

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index aef74773..81fe4ee8 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -11,5 +11,18 @@ jobs:
       RACK_ENV: test
     steps:
       - uses: actions/checkout@v3
+      - name: Set up Ruby # Only install ruby to get Rubocop
+        uses: ruby/setup-ruby@v1
+        with:
+          ruby-version: '3.2.2'
+      - name: Lint with Rubocop
+        run: |
+          gem install rubocop
+          rubocop
+      - name: Lint with Eslint
+        run: |
+          cd ./Frontend
+          npm install
+          npm run lint
       - name: Start containers
         run: docker compose -f "docker-compose.test.yml" up wca_registration_handler --abort-on-container-exit
diff --git a/.rubocop.yml b/.rubocop.yml
new file mode 100644
index 00000000..03b29316
--- /dev/null
+++ b/.rubocop.yml
@@ -0,0 +1,227 @@
+AllCops:
+  TargetRubyVersion: 3.2.2
+  DisplayCopNames: true
+  NewCops: enable
+  Exclude:
+    - 'node_modules/**/*'
+    - 'Frontend/**/*'
+    - 'bin/**/*'
+    - 'vendor/**/*'
+
+Bundler/OrderedGems:
+  Enabled: false
+
+Lint/EmptyWhen:
+  Enabled: false
+
+Lint/UnusedBlockArgument:
+  Enabled: false
+
+Lint/UnusedMethodArgument:
+  Enabled: false
+
+Naming/AccessorMethodName:
+  Enabled: false
+
+Style/Alias:
+  Enabled: false
+
+Style/EmptyMethod:
+  EnforcedStyle: expanded
+
+Style/RedundantSelf:
+  Enabled: false
+
+Style/SafeNavigation:
+  Enabled: false
+
+Style/StringLiterals:
+  # EnforcedStyle: double_quotes
+  Enabled: false
+
+Style/TrailingCommaInArguments:
+  # If `comma`, the cop requires a comma after the last argument, but only for
+  # parenthesized method calls where each argument is on its own line.
+  # If `consistent_comma`, the cop requires a comma after the last argument,
+  # for all parenthesized method calls with arguments.
+  EnforcedStyleForMultiline: comma
+
+Style/TrailingCommaInArrayLiteral:
+  # If `comma`, the cop requires a comma after the last argument, but only for
+  # parenthesized method calls where each argument is on its own line.
+  # If `consistent_comma`, the cop requires a comma after the last argument,
+  # for all parenthesized method calls with arguments.
+  EnforcedStyleForMultiline: comma
+
+Style/TrailingCommaInHashLiteral:
+  # If `comma`, the cop requires a comma after the last item in an array or
+  # hash, but only when each item is on its own line.
+  # If `consistent_comma`, the cop requires a comma after the last item of all
+  # non-empty array and hash literals.
+  EnforcedStyleForMultiline: comma
+
+Style/GuardClause:
+  Enabled: false
+
+Metrics/AbcSize:
+  Enabled: false
+
+Metrics/BlockLength:
+  Enabled: false
+
+Metrics/BlockNesting:
+  Enabled: false
+
+Metrics/ClassLength:
+  Enabled: false
+
+Metrics/CyclomaticComplexity:
+  Max: 23
+
+Metrics/ParameterLists:
+  Max: 5
+  CountKeywordArgs: false
+
+Metrics/PerceivedComplexity:
+  Max: 25
+
+Layout/LineLength:
+  Max: 245
+
+Metrics/MethodLength:
+  Enabled: false
+
+Metrics/ModuleLength:
+  Enabled: false
+
+Naming/MemoizedInstanceVariableName:
+  Enabled: false
+
+Style/AccessModifierDeclarations:
+  Enabled: false
+
+Style/AsciiComments:
+  Enabled: false
+
+Style/BlockDelimiters:
+  Enabled: false
+
+Style/ClassAndModuleChildren:
+  Enabled: false
+
+Style/ClassVars:
+  Enabled: false
+
+Style/ConditionalAssignment:
+  Enabled: false
+
+Style/Documentation:
+  Enabled: false
+
+Style/DoubleNegation:
+  Enabled: false
+
+Style/EmptyElse:
+  EnforcedStyle: empty
+
+Style/IfInsideElse:
+  Enabled: false
+
+Style/IfUnlessModifier:
+  Enabled: false
+
+Style/InverseMethods:
+  Enabled: false
+
+Style/Lambda:
+  Enabled: false
+
+Style/MultilineBlockChain:
+  Enabled: false
+
+Style/NegatedIf:
+  Enabled: false
+
+Style/Next:
+  Enabled: false
+
+Style/NumericPredicate:
+  Enabled: false
+
+Style/PercentLiteralDelimiters:
+  Enabled: false
+
+Style/PerlBackrefs:
+  Enabled: false
+
+Style/RaiseArgs:
+  EnforcedStyle: compact
+
+Style/RedundantParentheses:
+  Enabled: false
+
+Style/SignalException:
+  EnforcedStyle: only_raise
+
+Layout/SpaceAroundOperators:
+  Enabled: false
+
+Layout/IndentationConsistency:
+  EnforcedStyle: indented_internal_methods
+
+Style/StringLiteralsInInterpolation:
+  Enabled: false
+
+Style/SymbolArray:
+  Enabled: false
+
+Style/WordArray:
+  Enabled: false
+
+Style/SymbolProc:
+  Enabled: false
+
+Naming/PredicateName:
+  Enabled: false
+
+Naming/BlockParameterName:
+  Enabled: false
+
+Naming/MethodParameterName:
+  Enabled: false
+
+Style/YodaCondition:
+  Enabled: false
+
+Style/FormatStringToken:
+  Enabled: false
+
+Layout/EmptyLineAfterGuardClause:
+  Enabled: false
+
+Lint/EmptyFile:
+  Exclude:
+    - 'db/seeds.rb'
+
+# We have too many event IDs and Comp Years with numbers in them
+Naming/VariableNumber:
+  Enabled: false
+
+# If an external library requires us to use terms like "blacklist",
+# we have no choice but to follow their conventions until they update
+Naming/InclusiveLanguage:
+  Exclude:
+    - 'config/**/*'
+
+Style/OpenStructUse:
+  Exclude:
+    - 'spec/lib/middlewares/warden_user_logger_spec.rb'
+
+Style/HashSyntax:
+  EnforcedShorthandSyntax: never
+
+# These AWS Clients are set in the initializer
+Style/GlobalVars:
+  AllowedVariables:
+    - $sqs
+    - $dynamodb
\ No newline at end of file
diff --git a/Frontend/src/index.jsx b/Frontend/src/index.jsx
index cf22100f..aa1f4413 100644
--- a/Frontend/src/index.jsx
+++ b/Frontend/src/index.jsx
@@ -3,8 +3,8 @@ import '@thewca/wca-components/dist/index.esm.css'
 import React from 'react'
 import { createRoot } from 'react-dom/client'
 import { createBrowserRouter, Link, RouterProvider } from 'react-router-dom'
-import Registrations from './pages/registrations'
 import Register from './pages/register'
+import Registrations from './pages/registrations'
 
 const router = createBrowserRouter([
   {
diff --git a/Frontend/src/pages/register/components/RegistrationPanel.jsx b/Frontend/src/pages/register/components/RegistrationPanel.jsx
index 12c17715..8cf89e89 100644
--- a/Frontend/src/pages/register/components/RegistrationPanel.jsx
+++ b/Frontend/src/pages/register/components/RegistrationPanel.jsx
@@ -37,7 +37,7 @@ export default function RegistrationPanel() {
         handleEventSelection={handleEventSelection}
         events={EVENTS}
         initialSelected={[]}
-        size={'2x'}
+        size="2x"
       />
       <button
         onClick={(_) =>
diff --git a/Gemfile b/Gemfile
index 8c064d2a..38f78459 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,30 +1,32 @@
-source "https://rubygems.org"
-git_source(:github) { |repo| "https://github.com/thewca/wca-registration.git" }
+# frozen_string_literal: true
 
-ruby "3.2.2"
+source 'https://rubygems.org'
+git_source(:github) { |_repo| 'https://github.com/thewca/wca-registration.git' }
+
+ruby '3.2.2'
 
 # Gems that are only needed by the handler not the worker
 # Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main"
-gem "rails", "~> 7.0.4", ">= 7.0.4.3"
+gem 'rails', '~> 7.0.4', '>= 7.0.4.3'
 
 # Use sqlite3 as the database for Active Record
-gem "sqlite3", "~> 1.4"
+gem 'sqlite3', '~> 1.4'
 
 # Use the Puma web server [https://github.com/puma/puma]
-gem "puma", "~> 5.0"
+gem 'puma', '~> 5.0'
 
 # Build JSON APIs with ease [https://github.com/rails/jbuilder]
-gem "jbuilder"
+gem 'jbuilder'
 
 # Use Rack CORS for handling Cross-Origin Resource Sharing (CORS), making cross-origin AJAX possible
-gem "rack-cors"
+gem 'rack-cors'
 
 # Reduces boot times through caching; required in config/boot.rb
-gem "bootsnap", require: false
+gem 'bootsnap', require: false
 
 # Use Redis adapter to run Action Cable in production
-gem "redis", "~> 4.0"
 gem 'hiredis'
+gem 'redis', '~> 4.0'
 
 # DynamoDB for storing registrations
 gem 'aws-sdk-dynamodb'
@@ -33,21 +35,21 @@ gem 'aws-sdk-dynamodb'
 gem 'aws-sdk-sqs'
 
 # Use Kredis to get higher-level data types in Redis [https://github.com/rails/kredis]
-gem "kredis"
+gem 'kredis'
 
 # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
-gem "tzinfo-data", platforms: %i[ mingw mswin x64_mingw jruby ]
+gem 'tzinfo-data', platforms: %i[mingw mswin x64_mingw jruby]
 
 # vault for secrets management
 gem 'vault-rails'
 
 group :development, :test do
   # See https://guides.rubyonrails.org/debugging_rails_applications.html#debugging-with-the-debug-gem
-  gem "debug", platforms: %i[ mri mingw x64_mingw ]
+  gem 'debug', platforms: %i[mri mingw x64_mingw]
+  gem 'rubocop', require: false
 end
 
 group :development do
   # Speed up commands on slow machines / big apps [https://github.com/rails/spring]
   # gem "spring"
 end
-
diff --git a/Rakefile b/Rakefile
index 9a5ea738..488c551f 100644
--- a/Rakefile
+++ b/Rakefile
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 # Add your own tasks in files placed in lib/tasks ending in .rake,
 # for example lib/tasks/capistrano.rake, and they will automatically be available to Rake.
 
-require_relative "config/application"
+require_relative 'config/application'
 
 Rails.application.load_tasks
diff --git a/app/channels/application_cable/channel.rb b/app/channels/application_cable/channel.rb
index d6726972..9aec2305 100644
--- a/app/channels/application_cable/channel.rb
+++ b/app/channels/application_cable/channel.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ApplicationCable
   class Channel < ActionCable::Channel::Base
   end
diff --git a/app/channels/application_cable/connection.rb b/app/channels/application_cable/connection.rb
index 0ff5442f..8d6c2a1b 100644
--- a/app/channels/application_cable/connection.rb
+++ b/app/channels/application_cable/connection.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ApplicationCable
   class Connection < ActionCable::Connection::Base
   end
diff --git a/app/controllers/application_controller.rb b/app/controllers/application_controller.rb
index 4ac8823b..13c271fb 100644
--- a/app/controllers/application_controller.rb
+++ b/app/controllers/application_controller.rb
@@ -1,2 +1,4 @@
+# frozen_string_literal: true
+
 class ApplicationController < ActionController::API
 end
diff --git a/app/controllers/healthcheck_controller.rb b/app/controllers/healthcheck_controller.rb
index 23600ad0..ea97ef33 100644
--- a/app/controllers/healthcheck_controller.rb
+++ b/app/controllers/healthcheck_controller.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 class HealthcheckController < ApplicationController
   def index
-    render json: { status: "ok" }, status: :ok
+    render json: { status: 'ok' }, status: :ok
   end
 end
diff --git a/app/controllers/metrics_controller.rb b/app/controllers/metrics_controller.rb
index 7a0c4c3e..b3c5132d 100644
--- a/app/controllers/metrics_controller.rb
+++ b/app/controllers/metrics_controller.rb
@@ -1,16 +1,18 @@
+# frozen_string_literal: true
+
 require 'securerandom'
 class MetricsController < ApplicationController
   def index
     # Get the queue attributes
-    queue_url = $sqs.get_queue_url(queue_name: "registrations.fifo").queue_url
+    queue_url = $sqs.get_queue_url(queue_name: 'registrations.fifo').queue_url
     response = $sqs.get_queue_attributes({
-                queue_url: queue_url,
-                attribute_names: ["ApproximateNumberOfMessages"]
-              })
+                                           queue_url: queue_url,
+                                           attribute_names: ['ApproximateNumberOfMessages'],
+                                         })
 
     # Get the queue size
-    queue_size = response.attributes["ApproximateNumberOfMessages"].to_i
+    queue_size = response.attributes['ApproximateNumberOfMessages'].to_i
 
-    render json: { queue_size: queue_size}
+    render json: { queue_size: queue_size }
   end
 end
diff --git a/app/controllers/registration_controller.rb b/app/controllers/registration_controller.rb
index 015b4b7f..b2c7af39 100644
--- a/app/controllers/registration_controller.rb
+++ b/app/controllers/registration_controller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'securerandom'
 require_relative '../helpers/competition_api'
 require_relative '../helpers/competitor_api'
@@ -8,7 +10,7 @@ def create
     competition_id = params[:competition_id]
     event_ids = params[:event_ids]
 
-    unless validate_request(competitor_id, competition_id) and !event_ids.empty?
+    unless validate_request(competitor_id, competition_id) && !event_ids.empty?
       return render json: { status: 'User cannot register for competition' }, status: :forbidden
     end
 
@@ -18,19 +20,20 @@ def create
       competitor_id: competitor_id,
       competition_id: competition_id,
       event_ids: event_ids,
-      registration_status: "waiting",
-      step: "Event Registration"
+      registration_status: 'waiting',
+      step: 'Event Registration',
     }
-    @queue ||= Aws::SQS::Queue.new($sqs.get_queue_url(queue_name: "registrations.fifo").queue_url)
+    queue_url = $sqs.get_queue_url(queue_name: 'registrations.fifo').queue_url
+    @queue ||= Aws::SQS::Queue.new(queue_url)
 
     @queue.send_message({
-     queue_url: $queue,
-     message_body: step_data.to_json,
-     message_group_id: id,
-     message_deduplication_id: id
-     })
+                          queue_url: queue_url,
+                          message_body: step_data.to_json,
+                          message_group_id: id,
+                          message_deduplication_id: id,
+                        })
 
-    render json: { status: 'ok', message: "Started Registration Process" }
+    render json: { status: 'ok', message: 'Started Registration Process' }
   end
 
   def update
@@ -45,26 +48,27 @@ def update
     # Specify the key attributes for the item to be updated
     key = {
       'competitor_id' => competitor_id,
-      'competition_id' => competition_id
+      'competition_id' => competition_id,
     }
 
     # Set the expression for the update operation
     update_expression = 'set registration_status = :s'
     expression_attribute_values = {
-      ':s' => status
+      ':s' => status,
     }
 
     begin
       # Update the item in the table
       $dynamodb.update_item({
-         table_name: "Registrations",
-         key: key,
-         update_expression: update_expression,
-         expression_attribute_values: expression_attribute_values
-       })
-      return render json: { status: 'ok' }
+                              table_name: 'Registrations',
+                              key: key,
+                              update_expression: update_expression,
+                              expression_attribute_values: expression_attribute_values,
+                            })
+      render json: { status: 'ok' }
     rescue Aws::DynamoDB::Errors::ServiceError => e
-      return render json: { status: 'Failed to update registration data' }, status: :internal_server_error
+      puts e # TODO: Expose this as a metric
+      render json: { status: 'Failed to update registration data' }, status: :internal_server_error
     end
   end
 
@@ -78,25 +82,27 @@ def delete
 
     # Define the key of the item to delete
     key = {
-      "competition_id" => competition_id,
-      "competitor_id" => competitor_id
+      'competition_id' => competition_id,
+      'competitor_id' => competitor_id,
     }
 
     begin
       # Call the delete_item method to delete the item from the table
       $dynamodb.delete_item(
-        table_name: "Registrations",
-        key: key
+        table_name: 'Registrations',
+        key: key,
       )
 
       # Render a success response
-      return render json: { status: 'ok' }
-
-    rescue Aws::DynamoDB::Errors::ServiceError => error
+      render json: { status: 'ok' }
+    rescue Aws::DynamoDB::Errors::ServiceError => e
       # Render an error response
-      return render json: { status: "Error deleting item from DynamoDB: #{error.message}" }, status: :internal_server_error
+      puts e # TODO: Expose this as a metric
+      render json: { status: "Error deleting item from DynamoDB: #{e.message}" },
+             status: :internal_server_error
     end
   end
+
   def list
     competition_id = params[:competition_id]
     registrations = get_registrations(competition_id)
@@ -106,49 +112,47 @@ def list
 
   private
 
-  REGISTRATION_STATUS = %w[waiting accepted]
+    REGISTRATION_STATUS = %w[waiting accepted].freeze
 
-  def user_exists(competitor_id)
-    Rails.cache.fetch(competitor_id,expires_in: 12.hours) do
-      CompetitorApi.check_competitor(competitor_id)
+    def user_exists(competitor_id)
+      Rails.cache.fetch(competitor_id, expires_in: 12.hours) do
+        CompetitorApi.check_competitor(competitor_id)
+      end
     end
-  end
 
-  def competition_open(competition_id)
-    Rails.cache.fetch(competition_id, expires_in: 5.minutes) do
-      CompetitionApi.check_competition(competition_id)
+    def competition_open(competition_id)
+      Rails.cache.fetch(competition_id, expires_in: 5.minutes) do
+        CompetitionApi.check_competition(competition_id)
+      end
     end
-  end
 
-  def can_user_register?(competitor_id, competition_id)
-    # Check if user exists
-    user_exists(competitor_id) and competition_open(competition_id)
-  end
+    def can_user_register?(competitor_id, competition_id)
+      # Check if user exists
+      user_exists(competitor_id) and competition_open(competition_id)
+    end
 
-  def validate_request(competitor_id, competition_id, status="waiting")
-    if competitor_id.present? and competitor_id =~ /^\d{4}[a-zA-Z]{4}\d{2}$/
-      puts 'correct competitor_id'
-      if competition_id =~ /^[a-zA-Z]+\d{4}$/ and REGISTRATION_STATUS.include? status
-        puts 'correct competition id and status'
-        return can_user_register?(competitor_id, competition_id)
+    def validate_request(competitor_id, competition_id, status = 'waiting')
+      if competitor_id.present? && competitor_id =~ (/^\d{4}[a-zA-Z]{4}\d{2}$/)
+        puts 'correct competitor_id'
+        if competition_id =~ (/^[a-zA-Z]+\d{4}$/) && REGISTRATION_STATUS.include?(status)
+          puts 'correct competition id and status'
+          can_user_register?(competitor_id, competition_id)
+        end
+      else
+        false
       end
-    else
-      false
     end
-  end
-
 
-
-  def get_registrations(competition_id)
-    # Query DynamoDB for registrations with the given competition_id
-    resp = $dynamodb.query({
-      table_name: 'Registrations',
-      key_condition_expression: '#ci = :cid',
-      expression_attribute_names: { '#ci' => 'competition_id' },
-      expression_attribute_values: { ':cid' => competition_id }
-    })
-
-    # Return the items from the response
-    resp.items
-  end
+    def get_registrations(competition_id)
+      # Query DynamoDB for registrations with the given competition_id
+      resp = $dynamodb.query({
+                               table_name: 'Registrations',
+                               key_condition_expression: '#ci = :cid',
+                               expression_attribute_names: { '#ci' => 'competition_id' },
+                               expression_attribute_values: { ':cid' => competition_id },
+                             })
+
+      # Return the items from the response
+      resp.items
+    end
 end
diff --git a/app/helpers/competition_api.rb b/app/helpers/competition_api.rb
index e97275cc..80b22e95 100644
--- a/app/helpers/competition_api.rb
+++ b/app/helpers/competition_api.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'uri'
 require 'net/http'
 require 'json'
@@ -9,7 +10,7 @@ def self.check_competition(competition_id)
     res = Net::HTTP.get_response(uri)
     if res.is_a?(Net::HTTPSuccess)
       body = JSON.parse res.body
-      body["registration_open"].present?
+      body['registration_open'].present?
     else
       # The Competition Service is unreachable TODO We should track this as a metric
       puts 'network request failed'
diff --git a/app/helpers/competitor_api.rb b/app/helpers/competitor_api.rb
index 1a67341b..312b44d3 100644
--- a/app/helpers/competitor_api.rb
+++ b/app/helpers/competitor_api.rb
@@ -1,4 +1,5 @@
 # frozen_string_literal: true
+
 require 'uri'
 require 'net/http'
 require 'json'
@@ -9,7 +10,7 @@ def self.check_competitor(competitor_id)
     res = Net::HTTP.get_response(uri)
     if res.is_a?(Net::HTTPSuccess)
       body = JSON.parse res.body
-      body["user"].present?
+      body['user'].present?
     else
       # The Competitor Service is unreachable TODO We should track this as a metric
       puts 'network request failed'
diff --git a/app/jobs/application_job.rb b/app/jobs/application_job.rb
index d394c3d1..bef39599 100644
--- a/app/jobs/application_job.rb
+++ b/app/jobs/application_job.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ApplicationJob < ActiveJob::Base
   # Automatically retry jobs that encountered a deadlock
   # retry_on ActiveRecord::Deadlocked
diff --git a/app/mailers/application_mailer.rb b/app/mailers/application_mailer.rb
index 3c34c814..d84cb6e7 100644
--- a/app/mailers/application_mailer.rb
+++ b/app/mailers/application_mailer.rb
@@ -1,4 +1,6 @@
+# frozen_string_literal: true
+
 class ApplicationMailer < ActionMailer::Base
-  default from: "from@example.com"
-  layout "mailer"
+  default from: 'from@example.com'
+  layout 'mailer'
 end
diff --git a/app/models/application_record.rb b/app/models/application_record.rb
index b63caeb8..08dc5379 100644
--- a/app/models/application_record.rb
+++ b/app/models/application_record.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 class ApplicationRecord < ActiveRecord::Base
   primary_abstract_class
 end
diff --git a/app/worker/queue_poller.rb b/app/worker/queue_poller.rb
index 94d47ce1..89b69fac 100644
--- a/app/worker/queue_poller.rb
+++ b/app/worker/queue_poller.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'json'
 require 'aws-sdk-sqs'
 require_relative 'registration_processor'
@@ -9,13 +11,13 @@ class QueuePoller
   MAX_MESSAGES = 10
 
   def self.perform
-    if ENV['LOCALSTACK_ENDPOINT']
-      @sqs ||= Aws::SQS::Client.new(endpoint: ENV['LOCALSTACK_ENDPOINT'])
-    else
-      @sqs ||= Aws::SQS::Client.new
-    end
+    @sqs ||= if ENV['LOCALSTACK_ENDPOINT']
+               Aws::SQS::Client.new(endpoint: ENV['LOCALSTACK_ENDPOINT'])
+             else
+               Aws::SQS::Client.new
+             end
 
-    queue = @sqs.get_queue_url(queue_name: "registrations.fifo").queue_url
+    queue = @sqs.get_queue_url(queue_name: 'registrations.fifo').queue_url
     poller = Aws::SQS::QueuePoller.new(queue)
     poller.poll(wait_time_seconds: WAIT_TIME, max_number_of_messages: MAX_MESSAGES) do |messages|
       messages.each do |msg|
diff --git a/app/worker/registration_processor.rb b/app/worker/registration_processor.rb
index 3211b926..7e39b572 100644
--- a/app/worker/registration_processor.rb
+++ b/app/worker/registration_processor.rb
@@ -1,31 +1,31 @@
+# frozen_string_literal: true
+
 require 'aws-sdk-dynamodb'
 
 class RegistrationProcessor
   def self.process_message(message)
-    if ENV['LOCALSTACK_ENDPOINT']
-      @dynamodb ||= Aws::DynamoDB::Client.new(endpoint: ENV['LOCALSTACK_ENDPOINT'])
-    else
-      @dynamodb ||= Aws::DynamoDB::Client.new
-    end
+    @dynamodb ||= if ENV['LOCALSTACK_ENDPOINT']
+                    Aws::DynamoDB::Client.new(endpoint: ENV['LOCALSTACK_ENDPOINT'])
+                  else
+                    Aws::DynamoDB::Client.new
+                  end
     # implement your message processing logic here
     puts "Working on Message: #{message}"
-    if message['step'] == "Event Registration"
-      registration = {
-        competitor_id: message['competitor_id'],
-        competition_id: message['competition_id'],
-        event_ids: message['event_ids'],
-        registration_status: "waiting",
-      }
-      save_registration(registration)
-    end
-  end
+    return unless message['step'] == 'Event Registration'
 
-  private
+    registration = {
+      competitor_id: message['competitor_id'],
+      competition_id: message['competition_id'],
+      event_ids: message['event_ids'],
+      registration_status: 'waiting',
+    }
+    save_registration(registration)
+  end
 
   def self.save_registration(registration)
     @dynamodb.put_item({
-       table_name: 'Registrations',
-       item: registration
-     })
+                         table_name: 'Registrations',
+                         item: registration,
+                       })
   end
 end
diff --git a/bin/bundle b/bin/bundle
index 756fe4f7..7f4ac96e 100755
--- a/bin/bundle
+++ b/bin/bundle
@@ -8,46 +8,46 @@
 # this file is here to facilitate running it.
 #
 
-require "rubygems"
+require 'rubygems'
 
 m = Module.new do
   module_function
 
   def invoked_as_script?
-    File.expand_path($0) == File.expand_path(__FILE__)
+    File.expand_path($PROGRAM_NAME) == File.expand_path(__FILE__)
   end
 
   def env_var_version
-    ENV["BUNDLER_VERSION"]
+    ENV['BUNDLER_VERSION']
   end
 
   def cli_arg_version
     return unless invoked_as_script? # don't want to hijack other binstubs
-    return unless "update".start_with?(ARGV.first || " ") # must be running `bundle update`
+    return unless 'update'.start_with?(ARGV.first || ' ') # must be running `bundle update`
+
     bundler_version = nil
     update_index = nil
     ARGV.each_with_index do |a, i|
-      if update_index && update_index.succ == i && a =~ Gem::Version::ANCHORED_VERSION_PATTERN
-        bundler_version = a
-      end
+      bundler_version = a if update_index && update_index.succ == i && a =~ Gem::Version::ANCHORED_VERSION_PATTERN
       next unless a =~ /\A--bundler(?:[= ](#{Gem::Version::VERSION_PATTERN}))?\z/
-      bundler_version = $1
+
+      bundler_version = Regexp.last_match(1)
       update_index = i
     end
     bundler_version
   end
 
   def gemfile
-    gemfile = ENV["BUNDLE_GEMFILE"]
+    gemfile = ENV['BUNDLE_GEMFILE']
     return gemfile if gemfile && !gemfile.empty?
 
-    File.expand_path("../../Gemfile", __FILE__)
+    File.expand_path('../Gemfile', __dir__)
   end
 
   def lockfile
     lockfile =
       case File.basename(gemfile)
-      when "gems.rb" then gemfile.sub(/\.rb$/, gemfile)
+      when 'gems.rb' then gemfile.sub(/\.rb$/, gemfile)
       else "#{gemfile}.lock"
       end
     File.expand_path(lockfile)
@@ -55,15 +55,17 @@ m = Module.new do
 
   def lockfile_version
     return unless File.file?(lockfile)
+
     lockfile_contents = File.read(lockfile)
     return unless lockfile_contents =~ /\n\nBUNDLED WITH\n\s{2,}(#{Gem::Version::VERSION_PATTERN})\n/
+
     Regexp.last_match(1)
   end
 
   def bundler_requirement
     @bundler_requirement ||=
       env_var_version || cli_arg_version ||
-        bundler_requirement_for(lockfile_version)
+      bundler_requirement_for(lockfile_version)
   end
 
   def bundler_requirement_for(version)
@@ -73,28 +75,32 @@ m = Module.new do
 
     requirement = bundler_gem_version.approximate_recommendation
 
-    return requirement unless Gem::Version.new(Gem::VERSION) < Gem::Version.new("2.7.0")
+    return requirement unless Gem::Version.new(Gem::VERSION) < Gem::Version.new('2.7.0')
 
-    requirement += ".a" if bundler_gem_version.prerelease?
+    requirement += '.a' if bundler_gem_version.prerelease?
 
     requirement
   end
 
   def load_bundler!
-    ENV["BUNDLE_GEMFILE"] ||= gemfile
+    ENV['BUNDLE_GEMFILE'] ||= gemfile
 
     activate_bundler
   end
 
   def activate_bundler
     gem_error = activation_error_handling do
-      gem "bundler", bundler_requirement
+      gem 'bundler', bundler_requirement
     end
     return if gem_error.nil?
+
     require_error = activation_error_handling do
-      require "bundler/version"
+      require 'bundler/version'
+    end
+    if require_error.nil? && Gem::Requirement.new(bundler_requirement).satisfied_by?(Gem::Version.new(Bundler::VERSION))
+      return
     end
-    return if require_error.nil? && Gem::Requirement.new(bundler_requirement).satisfied_by?(Gem::Version.new(Bundler::VERSION))
+
     warn "Activating bundler (#{bundler_requirement}) failed:\n#{gem_error.message}\n\nTo install the version of bundler this project requires, run `gem install bundler -v '#{bundler_requirement}'`"
     exit 42
   end
@@ -109,6 +115,4 @@ end
 
 m.load_bundler!
 
-if m.invoked_as_script?
-  load Gem.bin_path("bundler", "bundle")
-end
+load Gem.bin_path('bundler', 'bundle') if m.invoked_as_script?
diff --git a/bin/rails b/bin/rails
index efc03774..a31728ab 100755
--- a/bin/rails
+++ b/bin/rails
@@ -1,4 +1,6 @@
 #!/usr/bin/env ruby
-APP_PATH = File.expand_path("../config/application", __dir__)
-require_relative "../config/boot"
-require "rails/commands"
+# frozen_string_literal: true
+
+APP_PATH = File.expand_path('../config/application', __dir__)
+require_relative '../config/boot'
+require 'rails/commands'
diff --git a/bin/rake b/bin/rake
index 4fbf10b9..c1999550 100755
--- a/bin/rake
+++ b/bin/rake
@@ -1,4 +1,6 @@
 #!/usr/bin/env ruby
-require_relative "../config/boot"
-require "rake"
+# frozen_string_literal: true
+
+require_relative '../config/boot'
+require 'rake'
 Rake.application.run
diff --git a/bin/setup b/bin/setup
index ec47b79b..516b651e 100755
--- a/bin/setup
+++ b/bin/setup
@@ -1,8 +1,10 @@
 #!/usr/bin/env ruby
-require "fileutils"
+# frozen_string_literal: true
+
+require 'fileutils'
 
 # path to your application root.
-APP_ROOT = File.expand_path("..", __dir__)
+APP_ROOT = File.expand_path('..', __dir__)
 
 def system!(*args)
   system(*args) || abort("\n== Command #{args} failed ==")
@@ -13,9 +15,9 @@ FileUtils.chdir APP_ROOT do
   # This script is idempotent, so that you can run it at any time and get an expectable outcome.
   # Add necessary setup steps to this file.
 
-  puts "== Installing dependencies =="
-  system! "gem install bundler --conservative"
-  system("bundle check") || system!("bundle install")
+  puts '== Installing dependencies =='
+  system! 'gem install bundler --conservative'
+  system('bundle check') || system!('bundle install')
 
   # puts "\n== Copying sample files =="
   # unless File.exist?("config/database.yml")
@@ -23,11 +25,11 @@ FileUtils.chdir APP_ROOT do
   # end
 
   puts "\n== Preparing database =="
-  system! "bin/rails db:prepare"
+  system! 'bin/rails db:prepare'
 
   puts "\n== Removing old logs and tempfiles =="
-  system! "bin/rails log:clear tmp:clear"
+  system! 'bin/rails log:clear tmp:clear'
 
   puts "\n== Restarting application server =="
-  system! "bin/rails restart"
+  system! 'bin/rails restart'
 end
diff --git a/config.ru b/config.ru
index 4a3c09a6..6dc83218 100644
--- a/config.ru
+++ b/config.ru
@@ -1,6 +1,8 @@
+# frozen_string_literal: true
+
 # This file is used by Rack-based servers to start the application.
 
-require_relative "config/environment"
+require_relative 'config/environment'
 
 run Rails.application
 Rails.application.load_server
diff --git a/config/application.rb b/config/application.rb
index f87e984f..bc1ef8ef 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -1,6 +1,8 @@
-require_relative "boot"
+# frozen_string_literal: true
 
-require "rails/all"
+require_relative 'boot'
+
+require 'rails/all'
 
 # Require the gems listed in Gemfile, including any gems
 # you've limited to :test, :development, or :production.
diff --git a/config/boot.rb b/config/boot.rb
index 988a5ddc..c04863fa 100644
--- a/config/boot.rb
+++ b/config/boot.rb
@@ -1,4 +1,6 @@
-ENV["BUNDLE_GEMFILE"] ||= File.expand_path("../Gemfile", __dir__)
+# frozen_string_literal: true
 
-require "bundler/setup" # Set up gems listed in the Gemfile.
-require "bootsnap/setup" # Speed up boot time by caching expensive operations.
+ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../Gemfile', __dir__)
+
+require 'bundler/setup' # Set up gems listed in the Gemfile.
+require 'bootsnap/setup' # Speed up boot time by caching expensive operations.
diff --git a/config/environment.rb b/config/environment.rb
index cac53157..d5abe558 100644
--- a/config/environment.rb
+++ b/config/environment.rb
@@ -1,5 +1,7 @@
+# frozen_string_literal: true
+
 # Load the Rails application.
-require_relative "application"
+require_relative 'application'
 
 # Initialize the Rails application.
 Rails.application.initialize!
diff --git a/config/environments/development.rb b/config/environments/development.rb
index 3d6b0736..43dffb15 100644
--- a/config/environments/development.rb
+++ b/config/environments/development.rb
@@ -1,4 +1,6 @@
-require "active_support/core_ext/integer/time"
+# frozen_string_literal: true
+
+require 'active_support/core_ext/integer/time'
 
 Rails.application.configure do
   # Settings specified here will take precedence over those in config/application.rb.
@@ -19,10 +21,10 @@
 
   # Enable/disable caching. By default caching is disabled.
   # Run rails dev:cache to toggle caching.
-  if Rails.root.join("tmp/caching-dev.txt").exist?
+  if Rails.root.join('tmp/caching-dev.txt').exist?
     config.cache_store = :memory_store
     config.public_file_server.headers = {
-      "Cache-Control" => "public, max-age=#{2.days.to_i}"
+      'Cache-Control' => "public, max-age=#{2.days.to_i}",
     }
   else
     config.action_controller.perform_caching = false
@@ -53,7 +55,6 @@
   # Highlight code that triggered database queries in logs.
   config.active_record.verbose_query_logs = true
 
-
   # Raises error for missing translations.
   # config.i18n.raise_on_missing_translations = true
 
diff --git a/config/environments/production.rb b/config/environments/production.rb
index 3aef63b7..2d2fbe70 100644
--- a/config/environments/production.rb
+++ b/config/environments/production.rb
@@ -1,12 +1,14 @@
-require "active_support/core_ext/integer/time"
+# frozen_string_literal: true
+
+require 'active_support/core_ext/integer/time'
 
 Rails.application.configure do
   # Settings specified here will take precedence over those in config/application.rb.
-  config.hosts << "registration.worldcubeassociation.org"
+  config.hosts << 'registration.worldcubeassociation.org'
 
   # Exclude requests for the /healthcheck/ path from host checking
   Rails.application.config.host_authorization = {
-    exclude: ->(request) { request.path =~ /healthcheck/ }
+    exclude: ->(request) { request.path =~ /healthcheck/ },
   }
 
   # Code is not reloaded between requests.
@@ -19,7 +21,7 @@
   config.eager_load = true
 
   # Full error reports are disabled and caching is turned on.
-  config.consider_all_requests_local       = false
+  config.consider_all_requests_local = false
 
   # Ensures that a master key has been made available in either ENV["RAILS_MASTER_KEY"]
   # or in config/master.key. This key is used to decrypt credentials (and other encrypted files).
@@ -27,7 +29,7 @@
 
   # Disable serving static files from the `/public` folder by default since
   # Apache or NGINX already handles this.
-  config.public_file_server.enabled = ENV["RAILS_SERVE_STATIC_FILES"].present?
+  config.public_file_server.enabled = ENV['RAILS_SERVE_STATIC_FILES'].present?
 
   # Enable serving of images, stylesheets, and JavaScripts from an asset server.
   # config.asset_host = "http://assets.example.com"
@@ -52,7 +54,7 @@
   config.log_level = :info
 
   # Prepend all log lines with the following tags.
-  config.log_tags = [ :request_id ]
+  config.log_tags = [:request_id]
 
   # Use a different cache store in production.
   # config.cache_store = :mem_cache_store
@@ -75,14 +77,14 @@
   config.active_support.report_deprecations = false
 
   # Use default logging formatter so that PID and timestamp are not suppressed.
-  config.log_formatter = ::Logger::Formatter.new
+  config.log_formatter = Logger::Formatter.new
 
   # Use a different logger for distributed setups.
   # require "syslog/logger"
   # config.logger = ActiveSupport::TaggedLogging.new(Syslog::Logger.new "app-name")
 
-  if ENV["RAILS_LOG_TO_STDOUT"].present?
-    logger           = ActiveSupport::Logger.new(STDOUT)
+  if ENV['RAILS_LOG_TO_STDOUT'].present?
+    logger           = ActiveSupport::Logger.new($stdout)
     logger.formatter = config.log_formatter
     config.logger    = ActiveSupport::TaggedLogging.new(logger)
   end
diff --git a/config/environments/test.rb b/config/environments/test.rb
index 6ea4d1e7..02ea9872 100644
--- a/config/environments/test.rb
+++ b/config/environments/test.rb
@@ -1,4 +1,6 @@
-require "active_support/core_ext/integer/time"
+# frozen_string_literal: true
+
+require 'active_support/core_ext/integer/time'
 
 # The test environment is used exclusively to run your application's
 # test suite. You never need to work with it otherwise. Remember that
@@ -14,12 +16,12 @@
   # Eager loading loads your whole application. When running a single test locally,
   # this probably isn't necessary. It's a good idea to do in a continuous integration
   # system, or in some way before deploying your code.
-  config.eager_load = ENV["CI"].present?
+  config.eager_load = ENV['CI'].present?
 
   # Configure public file server for tests with Cache-Control for performance.
   config.public_file_server.enabled = true
   config.public_file_server.headers = {
-    "Cache-Control" => "public, max-age=#{1.hour.to_i}"
+    'Cache-Control' => "public, max-age=#{1.hour.to_i}",
   }
 
   # Show full error reports and disable caching.
diff --git a/config/initializers/_vault.rb b/config/initializers/_vault.rb
index 2dc7bac5..ce8b2fae 100644
--- a/config/initializers/_vault.rb
+++ b/config/initializers/_vault.rb
@@ -1,7 +1,7 @@
 # This file starts with _ because it has to be the first one run
-#frozen_string_literal: true
+# frozen_string_literal: true
 
-require "vault/rails"
+require 'vault/rails'
 
 Vault.configure do |vault|
   # Use Vault in transit mode for encrypting and decrypting data. If
@@ -15,10 +15,10 @@
   # prefixed with this application name. If you change the name of the
   # application, you will need to migrate the encrypted data to the new
   # key namespace. Default: ENV["VAULT_RAILS_APPLICATION"].
-  vault.application = "wca-registration"
+  vault.application = 'wca-registration'
 
   # The address of the Vault server, also read as ENV["VAULT_ADDR"]
-  vault.address = ENV.fetch("VAULT_ADDR")
+  vault.address = ENV.fetch('VAULT_ADDR')
 
   # The token to authenticate with Vault, for prod auth is done via AWS
   if Rails.env.production?
@@ -26,12 +26,11 @@
     # this is needed because otherwise we will assume the role of the underlying instance instead
     role_credentials = Aws::ECSCredentials.new(retries: 3)
 
-    Vault.auth.aws_iam(ENV["TASK_ROLE"], role_credentials, nil, "https://sts.#{ENV["AWS_REGION"]}.amazonaws.com")
+    Vault.auth.aws_iam(ENV.fetch('TASK_ROLE', nil), role_credentials, nil, "https://sts.#{ENV.fetch('AWS_REGION', nil)}.amazonaws.com")
   else
-    vault.token = ENV["VAULT_DEV_ROOT_TOKEN_ID"]
+    vault.token = ENV.fetch('VAULT_DEV_ROOT_TOKEN_ID', nil)
   end
 
-
   # Use SSL verification, also read as ENV["VAULT_SSL_VERIFY"]
   vault.ssl_verify = false
 
@@ -46,17 +45,14 @@
   vault.read_timeout = 30
 end
 
-
 # Read a secret from Vault.
 def read_secret(secret_name)
   Vault.with_retries(Vault::HTTPConnectionError, Vault::HTTPError) do |attempt, e|
-    if e
-      puts "Received exception #{e} from Vault - attempt #{attempt}"
-    end
+    puts "Received exception #{e} from Vault - attempt #{attempt}" if e
     secret = Vault.logical.read("secret/data/wca-registration/#{secret_name}")
     if secret.present?
       secret.data[:data][:value]
-    else # TODO should we hard error out here?
+    else # TODO: should we hard error out here?
       puts "Tried to read #{secret_name}, but doesn´t exist"
     end
   end
@@ -70,9 +66,8 @@ def create_secret(secret_name, value)
 
 # Initialize secrets for dev and test
 def init
-  create_secret("SECRET_KEY_BASE","a003fdc6f113ff7d295596a02192c7116a76724ba6d3071043eefdd16f05971be0dc58f244e67728757b2fb55ae7a41e1eb97c1fe247ddaeb6caa97cea32120c")
+  create_secret('SECRET_KEY_BASE',
+                'a003fdc6f113ff7d295596a02192c7116a76724ba6d3071043eefdd16f05971be0dc58f244e67728757b2fb55ae7a41e1eb97c1fe247ddaeb6caa97cea32120c')
 end
 
-unless Rails.env.production?
-  init
-end
+init unless Rails.env.production?
diff --git a/config/initializers/aws.rb b/config/initializers/aws.rb
index f554f378..270755ec 100644
--- a/config/initializers/aws.rb
+++ b/config/initializers/aws.rb
@@ -1,11 +1,12 @@
+# frozen_string_literal: true
+
 # config/initializers/aws.rb
 
 if Rails.env.production?
   $dynamodb = Aws::DynamoDB::Client.new
   $sqs = Aws::SQS::Client.new
-  $queue = ENV["QUEUE_URL"]
 else
   # We are using localstack to emulate AWS in dev
-  $dynamodb = Aws::DynamoDB::Client.new(endpoint: ENV['LOCALSTACK_ENDPOINT'])
-  $sqs = Aws::SQS::Client.new(endpoint: ENV['LOCALSTACK_ENDPOINT'])
+  $dynamodb = Aws::DynamoDB::Client.new(endpoint: ENV.fetch('LOCALSTACK_ENDPOINT', nil))
+  $sqs = Aws::SQS::Client.new(endpoint: ENV.fetch('LOCALSTACK_ENDPOINT', nil))
 end
diff --git a/config/initializers/cors.rb b/config/initializers/cors.rb
index 2f2d1b72..493e7448 100644
--- a/config/initializers/cors.rb
+++ b/config/initializers/cors.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 # Be sure to restart your server when you modify this file.
 
 # Avoid CORS issues when API is called from the frontend app.
@@ -8,22 +10,22 @@
 if Rails.env.development? || Rails.env.test?
   Rails.application.config.middleware.insert_before 0, Rack::Cors do
     allow do
-      origins "*"
+      origins '*'
 
-      resource "*",
+      resource '*',
                headers: :any,
-               methods: [:get, :post, :put, :patch, :delete, :options, :head]
+               methods: %i[get post put patch delete options head]
     end
   end
 
 else
   Rails.application.config.middleware.insert_before 0, Rack::Cors do
     allow do
-      origins "*.worldcubeassociation.org", "http://test.registration.worldcubeassociation.org.s3-website-us-west-2.amazonaws.com"
+      origins '*.worldcubeassociation.org', 'http://test.registration.worldcubeassociation.org.s3-website-us-west-2.amazonaws.com'
 
-      resource "*",
+      resource '*',
                headers: :any,
-               methods: [:get, :post, :put, :patch, :delete, :options, :head]
+               methods: %i[get post put patch delete options head]
     end
   end
 end
diff --git a/config/initializers/filter_parameter_logging.rb b/config/initializers/filter_parameter_logging.rb
index adc6568c..3df77c5b 100644
--- a/config/initializers/filter_parameter_logging.rb
+++ b/config/initializers/filter_parameter_logging.rb
@@ -1,8 +1,10 @@
+# frozen_string_literal: true
+
 # Be sure to restart your server when you modify this file.
 
 # Configure parameters to be filtered from the log file. Use this to limit dissemination of
 # sensitive information. See the ActiveSupport::ParameterFilter documentation for supported
 # notations and behaviors.
-Rails.application.config.filter_parameters += [
-  :passw, :secret, :token, :_key, :crypt, :salt, :certificate, :otp, :ssn
+Rails.application.config.filter_parameters += %i[
+  passw secret token _key crypt salt certificate otp ssn
 ]
diff --git a/config/initializers/inflections.rb b/config/initializers/inflections.rb
index 3860f659..6c78420e 100644
--- a/config/initializers/inflections.rb
+++ b/config/initializers/inflections.rb
@@ -1,3 +1,4 @@
+# frozen_string_literal: true
 # Be sure to restart your server when you modify this file.
 
 # Add new inflection rules using the following format. Inflections
diff --git a/config/puma.rb b/config/puma.rb
index f1661d44..82255837 100644
--- a/config/puma.rb
+++ b/config/puma.rb
@@ -1,28 +1,30 @@
+# frozen_string_literal: true
+
 # Puma can serve each request in a thread from an internal thread pool.
 # The `threads` method setting takes two numbers: a minimum and maximum.
 # Any libraries that use thread pools should be configured to match
 # the maximum value specified for Puma. Default is set to 5 threads for minimum
 # and maximum; this matches the default thread size of Active Record.
 #
-max_threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
-min_threads_count = ENV.fetch("RAILS_MIN_THREADS") { max_threads_count }
+max_threads_count = ENV.fetch('RAILS_MAX_THREADS', 5)
+min_threads_count = ENV.fetch('RAILS_MIN_THREADS') { max_threads_count }
 threads min_threads_count, max_threads_count
 
 # Specifies the `worker_timeout` threshold that Puma will use to wait before
 # terminating a worker in development environments.
 #
-worker_timeout 3600 if ENV.fetch("RAILS_ENV", "development") == "development"
+worker_timeout 3600 if ENV.fetch('RAILS_ENV', 'development') == 'development'
 
 # Specifies the `port` that Puma will listen on to receive requests; default is 3000.
 #
-port ENV.fetch("PORT") { 3000 }
+port ENV.fetch('PORT', 3000)
 
 # Specifies the `environment` that Puma will run in.
 #
-environment ENV.fetch("RAILS_ENV") { "development" }
+environment ENV.fetch('RAILS_ENV', 'development')
 
 # Specifies the `pidfile` that Puma will use.
-pidfile ENV.fetch("PIDFILE") { "tmp/pids/server.pid" }
+pidfile ENV.fetch('PIDFILE', 'tmp/pids/server.pid')
 
 # Specifies the number of `worker` to boot in clustered mode.
 # Workers are forked web server processes. If using threads and worker together
diff --git a/config/routes.rb b/config/routes.rb
index c1b6b632..075fad8b 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 Rails.application.routes.draw do
   get '/healthcheck', to: 'healthcheck#index'
   post '/register', to: 'registration#create'
diff --git a/db/seeds.rb b/db/seeds.rb
index 683a970a..0bf3b637 100644
--- a/db/seeds.rb
+++ b/db/seeds.rb
@@ -1,29 +1,31 @@
+# frozen_string_literal: true
+
 # Create the DynamoDB Tables
 table_name = 'Registrations'
 key_schema = [
   { attribute_name: 'competition_id', key_type: 'HASH' },
-  { attribute_name: 'competitor_id', key_type: 'RANGE' }
+  { attribute_name: 'competitor_id', key_type: 'RANGE' },
 ]
 attribute_definitions = [
   { attribute_name: 'competition_id', attribute_type: 'S' },
-  { attribute_name: 'competitor_id', attribute_type: 'S' }
+  { attribute_name: 'competitor_id', attribute_type: 'S' },
 ]
 provisioned_throughput = {
   read_capacity_units: 5,
-  write_capacity_units: 5
+  write_capacity_units: 5,
 }
 $dynamodb.create_table({
- table_name: table_name,
- key_schema: key_schema,
- attribute_definitions: attribute_definitions,
- provisioned_throughput: provisioned_throughput
-})
+                         table_name: table_name,
+                         key_schema: key_schema,
+                         attribute_definitions: attribute_definitions,
+                         provisioned_throughput: provisioned_throughput,
+                       })
 
 # Create SQS Queue
 queue_name = 'registrations.fifo'
 $sqs.create_queue({
                     queue_name: queue_name,
                     attributes: {
-                      "FifoQueue": "true"
-                    }
+                      FifoQueue: 'true',
+                    },
                   })
diff --git a/test/channels/application_cable/connection_test.rb b/test/channels/application_cable/connection_test.rb
index 800405f1..4aee9b33 100644
--- a/test/channels/application_cable/connection_test.rb
+++ b/test/channels/application_cable/connection_test.rb
@@ -1,11 +1,15 @@
-require "test_helper"
+# frozen_string_literal: true
 
-class ApplicationCable::ConnectionTest < ActionCable::Connection::TestCase
-  # test "connects with cookies" do
-  #   cookies.signed[:user_id] = 42
-  #
-  #   connect
-  #
-  #   assert_equal connection.user_id, "42"
-  # end
+require 'test_helper'
+
+module ApplicationCable
+  class ConnectionTest < ActionCable::Connection::TestCase
+    # test "connects with cookies" do
+    #   cookies.signed[:user_id] = 42
+    #
+    #   connect
+    #
+    #   assert_equal connection.user_id, "42"
+    # end
+  end
 end
diff --git a/test/controllers/healthcheck_controller_test.rb b/test/controllers/healthcheck_controller_test.rb
index e2a212a0..90b2b3b0 100644
--- a/test/controllers/healthcheck_controller_test.rb
+++ b/test/controllers/healthcheck_controller_test.rb
@@ -1,4 +1,6 @@
-require "test_helper"
+# frozen_string_literal: true
+
+require 'test_helper'
 
 class HealthcheckControllerTest < ActionDispatch::IntegrationTest
   # test "the truth" do
diff --git a/test/controllers/registration_controller_test.rb b/test/controllers/registration_controller_test.rb
index eb2061e9..5992de8e 100644
--- a/test/controllers/registration_controller_test.rb
+++ b/test/controllers/registration_controller_test.rb
@@ -1,8 +1,9 @@
+# frozen_string_literal: true
+
 require 'test_helper'
 
 class RegistrationsControllerTest < ActionDispatch::IntegrationTest
   test 'should create registration' do
-
     assert true
   end
 end
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 353f1af7..4e3236ef 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -1,13 +1,17 @@
-ENV["RAILS_ENV"] ||= "test"
-require_relative "../config/environment"
-require "rails/test_help"
+# frozen_string_literal: true
 
-class ActiveSupport::TestCase
-  # Run tests in parallel with specified worker
-  parallelize(workers: :number_of_processors)
+ENV['RAILS_ENV'] ||= 'test'
+require_relative '../config/environment'
+require 'rails/test_help'
 
-  # Setup all fixtures in test/fixtures/*.yml for all tests in alphabetical order.
-  fixtures :all
+module ActiveSupport
+  class TestCase
+    # Run tests in parallel with specified worker
+    parallelize(workers: :number_of_processors)
 
-  # Add more helper methods to be used by all tests here...
+    # Setup all fixtures in test/fixtures/*.yml for all tests in alphabetical order.
+    fixtures :all
+
+    # Add more helper methods to be used by all tests here...
+  end
 end