First commit

2019-03-24 09:57:29 -04:00 · 2019-03-24 09:57:29 -04:00 · b9d38a5e9d
commit b9d38a5e9d
153 changed files with 18120 additions and 0 deletions
--- a/.dockerignore
+++ b/.dockerignore
@ -0,0 +1,5 @@
+example
+tmp
+web
+!web/build
+*.md
--- a/.gitignore
+++ b/.gitignore
@ -0,0 +1,22 @@
+### Go ###
+# Binaries for programs and plugins
+*.exe
+*.exe~
+*.dll
+*.so
+*.dylib
+
+# Test binary, built with `go test -c`
+*.test
+
+# Output of the go coverage tool, specifically when used with LiteIDE
+*.out
+
+### Go Patch ###
+/vendor
+/Godeps
+/tmp
+/tmp/runner-build
+/example/tmp
+
+.vscode
--- a/14
+++ b/14
@ -0,0 +1,14 @@
+FROM golang:1.12-stretch as builder
+COPY . /app
+WORKDIR /app
+ENV GO111MODULE=on
+RUN CGO_ENABLED=0 GOOS=linux go build -o service
+RUN go get github.com/pilu/fresh
+
+#second stage
+FROM alpine:latest
+WORKDIR /app
+RUN apk add --no-cache tzdata
+COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
+COPY --from=builder /app .
+CMD ./service
--- a/51
+++ b/51
@ -0,0 +1,51 @@
+The MIT License (MIT)
+
+Copyright (c) 2019-present Vikram Rangnekar
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+
+---
+
+Copyright (c) 2009 The Go Authors. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+    * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+    * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
--- a/README.md
+++ b/README.md
@ -0,0 +1,283 @@
+# Super Graph
+
+## Instant GraphQL API for Rails. Zero code.
+
+Get an instant high-performance GraphQL API for your Rails apps in seconds. Super Graph will auto learn your database structure and relationships. Built in support for Rails authentication and for JWT tokens.
+
+## Back story and motivation
+
+I have a Rails app that gets a bit of traffic. Having planned to improve the UI using React or Vue I found that my current APIs didn't have the data I needed. I was too lazy to build new controllers. My controllers were esentially wrappers around database queries and I didn't enjoy having to figure out new REST APIs with paths, names and methods to fetch all this new data.
+
+I always liked GraphQL and how simplifies things for web devs. On the backend however GraphQL seemed overly complex as it still required me to write a lot of the same database query code. I wanted a GraphQL server that just worked the second you deployed it without having to write a line of code.
+
+And so after a lot of coffee and some avocado toasts we now have Super Graph, an instant GraphQL API that is high performance and quick to deploy. One service to rule all your database querying needs.
+
+## Features
+- Support for Rails database conventions
+- Belongs-To, One-To-Many and Many-To-Many table relationships
+- Devise, Warden encrypted and signed session cookies
+- Redis, Memcache and Cookie session stores
+- Generates highly optimized Postgres SQL quries
+- Customize through a simple config file
+- High performance GoLang codebase
+- Tiny docker image and low memory requirements
+
+### GraphQL (GQL)
+
+We currently support the `query` action which is used for fetching data. Support
+for `mutation` and `subscriptions` is currently work in progress. For example the below query fetches two products that belong to the current user where the price is greater than 10
+
+#### GQL Query
+
+```gql
+query { 
+  users {
+    id
+    email
+    picture : avatar
+    password
+    full_name
+    products(limit: 2, where: { price: { gt: 10 } }) {
+      id
+      name
+      description
+      price
+    }
+  }
+}
+```
+
+The above GQL query returns the JSON result below. It handles all
+kinds of complexity without you writing a line of code. For example there is a while greater than `gt` and a limit clause on a child field. And the `avatar` field is renamed to `picture`. The `password` field is blocked and not returned. Finally the relationship between the `users` table and the `products` table is auto discovered and used.
+
+
+#### JSON Result
+
+```json
+{
+  "data": {
+    "users": [
+      {
+        "id": 1,
+        "email": "odilia@west.info",
+        "picture": "https://robohash.org/simur.png?size=300x300",
+        "full_name": "Edwin Orn",
+        "products": [
+          {
+            "id": 16,
+            "name": "Sierra Nevada Style Ale",
+            "description": "Belgian Abbey, 92 IBU, 4.7%, 17.4°Blg",
+            "price": 16.47
+          },
+          ...
+        ]
+      }
+    ]
+  }
+}
+```
+
+## Try it out
+
+Please be patient on the first run Go has to download packages and this
+can be a little slow.
+
+```console
+$ docker-compose run web rake db:create db:migrate db:seed
+$ docker-compose up
+$ open http://localhost:8080
+```
+
+In development mode you can use the `X-User-ID: 4` header to set a user id so you don't have to worries about cookies etc. This can be set using the *HTTP Headers* tab at the bottom of the web UI you'll see when you visit the above link. You can also directly run quries from the commandline like shown below.
+
+#### Querying the GQL endpoint
+
+```console
+curl 'http://localhost:8080/api/v1/graphql' \
+  -H 'content-type: application/json' \
+  -H 'X-User-ID: 5' \
+  --data-binary '{"query":"{ products { name price users { email }}}"}'
+```
+
+## How to GQL
+
+GQL is a simple query language that is fast replacing REST APIs. GQL is great
+since it allows web developers to fetch the exact data that they need without 
+depending on changes to backend code.
+
+The below query will fetch a `users` name, email and avatar image renamed as picture. If you also need the users `id` then just add it to the query.
+
+```gql
+query {
+  user {
+    full_name
+    email
+    picture : avatar
+  }
+}
+```
+
+Super Graph support complex quries where you can add filters, ordering, offsets and limits on the query.
+
+```javascript
+query {
+  products(
+    # returns only 30 items
+    limit: 30,
+
+    # starts from item 10, commented out for now
+    # offset: 10,
+
+    # orders the response items by highest price
+    order_by: { price: desc },
+
+    # no duplicate prices returned
+    distinct: [ price ]
+    
+    # only items with an id >= 30 and < 30 are returned
+    where: { id: { and: { greater_or_equals: 20, lt: 28 } } }) {
+    id
+    name
+    price
+  }
+}
+```
+
+## Web UI for web developers
+![Super Graph Web UI](web/public/super-graph-web-ui.png?raw=true "Super Graph Web UI for web developers")
+
+## Configuration
+
+Config files can either be in YAML or JSON their names are derived from the `GO_ENV` variable, for example `GO_ENV=prod` will cause the `prod.yaml` config file to be used. or `GO_ENV=dev` will use the `dev.yaml`. A path to the config files can be specified using the `-path <folder>` command line argument.
+
+```yaml
+host_port: 0.0.0.0:8080
+web_ui: true
+debug_level: 1
+
+# When to throw a 401 on auth failure 
+# valid values: always, per_query, never
+auth_fail_block: never
+
+# Postgres related enviroment Variables
+# SG_DATABASE_HOST
+# SG_DATABASE_PORT
+# SG_DATABASE_USER
+# SG_DATABASE_PASSWORD
+
+# Auth related enviroment Variables
+# SG_AUTH_SECRET_KEY_BASE
+# SG_AUTH_PUBLIC_KEY_FILE
+# SG_AUTH_URL
+# SG_AUTH_PASSWORD
+
+# inflections:
+#   person: people
+#   sheep: sheep
+
+auth:
+  type: header
+  field_name: X-User-ID
+
+# auth:
+#   type: rails
+#   cookie: _app_session
+#   store: cookie
+#   secret_key_base: caf335bfcfdb04e50db5bb0a4d67ab9...
+
+# auth:
+#   type: rails
+#   cookie: _app_session
+#   store: memcache
+#   host: 127.0.0.1
+
+# auth:
+#   type: rails
+#   cookie: _app_session
+#   store: redis
+#   max_idle: 80,
+#   max_active: 12000,
+#   url: redis://127.0.0.1:6379
+#   password: ""
+
+# auth:
+#   type: jwt
+#   cookie: _app_session
+#   secret: abc335bfcfdb04e50db5bb0a4d67ab9
+#   public_key_file: abc335bfcfdb04e50db5bb0a4d67ab9
+#   public_key_type: ecdsa #rsa
+
+database:
+  type: postgres
+  host: db
+  port: 5432
+  dbname: app_development
+  user: postgres
+  password: ''
+  #pool_size: 10
+  #max_retries: 0
+  #log_level: "debug" 
+
+  # Define variables here that you want to use in filters 
+  variables:
+    account_id: "select account_id from users where id = $user_id"
+
+  # Used to add access to tables 
+  filters:
+    users: "{ id: { _eq: $user_id } }"
+    posts: "{ account_id: { _eq: $account_id } }"
+
+  # Fields and table names that you wish to block
+  blacklist:
+    - secret
+    - password
+    - encrypted
+    - token
+```
+
+If deploying into enviroments like Kubernetes it's useful to be able to configure things like secrets and hosts though enviroment variables so we expose the following. This is escpecially useful for secrets since they are usually injected in via a secrets management framework ie. Kubernetes Secrets
+
+#### Postgres related enviroment Variables
+```console
+SG_DATABASE_HOST
+SG_DATABASE_PORT
+SG_DATABASE_USER
+SG_DATABASE_PASSWORD
+```
+
+#### Auth related enviroment Variables
+```console
+SG_AUTH_SECRET_KEY_BASE
+SG_AUTH_PUBLIC_KEY_FILE
+SG_AUTH_URL
+SG_AUTH_PASSWORD
+```
+
+## Deployment
+
+How do I deploy the Super Graph service with my existing rails app? You have several options here. Esentially you need to ensure your app's session cookie
+will be passed to this service. 
+
+#### Deploy under a subdomain
+For this to work you have to ensure that the option `:domain => :all` is added to your rails app config `Application.config.session_store` this will cause your rails app to create session cookies that can be shared with sub-domains. More info here <http://excid3.com/blog/sharing-a-devise-user-session-across-subdomains-with-rails-3/>
+
+#### We have this NGINX loadbalancer
+I'm sure you know how to configure it so that the graphql endpoint path is routed to wherever you have this service installed within your architecture.
+
+#### On Kubernetes
+If your existing rails app runs on Kubernetes then ensure you have an ingress config deployed that points the path `/api/v1/graphql` to the service that you have deployed Super Graph under.
+
+#### We use JWT tokens like those from Auth0
+In that case deploy under a subdomain and configure this service to use JWT authentication. You will need the public key file or secret key. Ensure your web app passes the JWT token with every GQL request in the Authorize header as a `bearer` token.
+
+## Contact me
+
+[twitter.com/dosco](https://twitter.com/dosco)
+
+## License
+
+[MIT](http://opensource.org/licenses/MIT)
+
+Copyright (c) 2019-present Vikram Rangnekar
+
+
--- a/dev.yml
+++ b/dev.yml
@ -0,0 +1,85 @@
+title: Super Graph Development
+host_port: 0.0.0.0:8080
+web_ui: true
+debug_level: 1
+
+# Throw a 401 on auth failure for queries that need auth
+# valid values: always, per_query, never
+auth_fail_block: never
+
+# Postgres related enviroment Variables
+# SG_DATABASE_HOST
+# SG_DATABASE_PORT
+# SG_DATABASE_USER
+# SG_DATABASE_PASSWORD
+
+# Auth related enviroment Variables
+# SG_AUTH_SECRET_KEY_BASE
+# SG_AUTH_PUBLIC_KEY_FILE
+# SG_AUTH_URL
+# SG_AUTH_PASSWORD
+
+# inflections:
+#   person: people
+#   sheep: sheep
+
+auth:
+  type: header
+  field_name: X-User-ID
+
+# auth:
+#   type: rails
+#   cookie: _app_session
+#   store: cookie
+#   secret_key_base: caf335bfcfdb04e50db5bb0a4d67ab9...
+
+# auth:
+#   type: rails
+#   cookie: _app_session
+#   store: memcache
+#   host: 127.0.0.1
+
+# auth:
+#   type: rails
+#   cookie: _app_session
+#   store: redis
+#   max_idle: 80,
+#   max_active: 12000,
+#   url: redis://127.0.0.1:6379
+#   password: ""
+
+# auth:
+#   type: jwt
+#   cookie: _app_session
+#   secret: abc335bfcfdb04e50db5bb0a4d67ab9
+#   public_key_file: abc335bfcfdb04e50db5bb0a4d67ab9
+#   public_key_type: ecdsa #rsa
+
+database:
+  type: postgres
+  host: db
+  port: 5432
+  dbname: app_development
+  user: postgres
+  password: ''
+  #pool_size: 10
+  #max_retries: 0
+  #log_level: "debug" 
+
+  # Define variables here that you want to use in filters 
+  variables:
+    account_id: "select account_id from users where id = $user_id"
+
+  # Used to add access to tables 
+  filters:
+    users: "{ id: { _eq: $user_id } }"
+    posts: "{ account_id: { _eq: $account_id } }"
+
+  # Fields and table names that you wish to block
+  blacklist:
+    - secret
+    - password
+    - encrypted
+    - token
+
+  
--- a/docker-compose.yml
+++ b/docker-compose.yml
@ -0,0 +1,30 @@
+version: '3.4'
+services:
+  db:
+    image: postgres
+
+  super_graph:
+    build:
+      context: .
+      target: builder
+    environment:
+      GO_ENV: "development"
+    depends_on:
+      - db
+    ports:
+      - "8080:8080"
+    volumes:
+      - .:/app
+    working_dir: /app
+    command: bash -c "fresh -c fresh.conf"
+    
+  web:
+    build: example/.
+    command: bash -c "rm -f tmp/pids/server.pid && bundle exec rails s -p 3000 -b '0.0.0.0'"
+    volumes:
+      - ./example:/app
+    ports:
+      - "3000:3000"
+    depends_on:
+      - db
+      - super_graph
--- a/example/.gitignore
+++ b/example/.gitignore
@ -0,0 +1,27 @@
+# See https://help.github.com/articles/ignoring-files for more about ignoring files.
+#
+# If you find yourself ignoring temporary files generated by your text editor
+# or operating system, you probably want to add a global ignore instead:
+#   git config --global core.excludesfile '~/.gitignore_global'
+
+# Ignore bundler config.
+/.bundle
+
+# Ignore all logfiles and tempfiles.
+/log/*
+/tmp/*
+!/log/.keep
+!/tmp/.keep
+
+# Ignore uploaded files in development
+/storage/*
+!/storage/.keep
+
+/node_modules
+/yarn-error.log
+
+/public/assets
+.byebug_history
+
+# Ignore master key for decrypting credentials and more.
+/config/master.key
--- a/example/.ruby-version
+++ b/example/.ruby-version
@ -0,0 +1 @@
+ruby-2.5.5
--- a/example/Dockerfile
+++ b/example/Dockerfile
@ -0,0 +1,17 @@
+FROM ruby:2.5
+RUN apt-get update -qq && apt-get install -y nodejs postgresql-client
+RUN mkdir /app
+WORKDIR /app
+COPY Gemfile /app/Gemfile
+COPY Gemfile.lock /app/Gemfile.lock
+RUN bundle install
+COPY . /app
+
+# Add a script to be executed every time the container starts.
+COPY entrypoint.sh /usr/bin/
+RUN chmod +x /usr/bin/entrypoint.sh
+ENTRYPOINT ["entrypoint.sh"]
+EXPOSE 3000
+
+# Start the main process.
+CMD ["rails", "server", "-b", "0.0.0.0"]
--- a/example/Gemfile
+++ b/example/Gemfile
@ -0,0 +1,65 @@
+source 'https://rubygems.org'
+git_source(:github) { |repo| "https://github.com/#{repo}.git" }
+
+ruby '2.5.5'
+
+# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
+gem 'rails', '~> 5.2.2', '>= 5.2.2.1'
+# Use postgresql as the database for Active Record
+gem 'pg', '>= 0.18', '< 2.0'
+# Use Puma as the app server
+gem 'puma', '~> 3.11'
+# Use SCSS for stylesheets
+gem 'sass-rails', '~> 5.0'
+# Use Uglifier as compressor for JavaScript assets
+gem 'uglifier', '>= 1.3.0'
+# See https://github.com/rails/execjs#readme for more supported runtimes
+# gem 'mini_racer', platforms: :ruby
+
+# Use CoffeeScript for .coffee assets and views
+gem 'coffee-rails', '~> 4.2'
+# Turbolinks makes navigating your web application faster. Read more: https://github.com/turbolinks/turbolinks
+gem 'turbolinks', '~> 5'
+# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
+gem 'jbuilder', '~> 2.5'
+# Use Redis adapter to run Action Cable in production
+# gem 'redis', '~> 4.0'
+# Use ActiveModel has_secure_password
+# gem 'bcrypt', '~> 3.1.7'
+
+# Use ActiveStorage variant
+# gem 'mini_magick', '~> 4.8'
+
+# Use Capistrano for deployment
+# gem 'capistrano-rails', group: :development
+
+# Reduces boot times through caching; required in config/boot.rb
+gem 'bootsnap', '>= 1.1.0', require: false
+
+group :development, :test do
+  # Call 'byebug' anywhere in the code to stop execution and get a debugger console
+  gem 'byebug', platforms: [:mri, :mingw, :x64_mingw]
+end
+
+group :development do
+  # Access an interactive console on exception pages or by calling 'console' anywhere in the code.
+  gem 'web-console', '>= 3.3.0'
+  gem 'listen', '>= 3.0.5', '< 3.2'
+  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
+  gem 'spring'
+  gem 'spring-watcher-listen', '~> 2.0.0'
+end
+
+group :test do
+  # Adds support for Capybara system testing and selenium driver
+  gem 'capybara', '>= 2.15'
+  gem 'selenium-webdriver'
+  # Easy installation and use of chromedriver to run system tests with Chrome
+  gem 'chromedriver-helper'
+end
+
+# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
+gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]
+
+gem 'devise'
+gem 'faker', :git => 'https://github.com/stympy/faker.git', :branch => 'master'
--- a/example/Gemfile.lock
+++ b/example/Gemfile.lock
@ -0,0 +1,267 @@
+GIT
+  remote: https://github.com/stympy/faker.git
+  revision: 32bac72d67d275bfb26ee7049efe5f3489fff3d0
+  branch: master
+  specs:
+    faker (1.9.3)
+      i18n (>= 0.7)
+      pastel (~> 0.7.2)
+      thor (~> 0.20.0)
+      tty-pager (~> 0.12.0)
+      tty-screen (~> 0.6.5)
+      tty-tree (~> 0.2.0)
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    actioncable (5.2.2.1)
+      actionpack (= 5.2.2.1)
+      nio4r (~> 2.0)
+      websocket-driver (>= 0.6.1)
+    actionmailer (5.2.2.1)
+      actionpack (= 5.2.2.1)
+      actionview (= 5.2.2.1)
+      activejob (= 5.2.2.1)
+      mail (~> 2.5, >= 2.5.4)
+      rails-dom-testing (~> 2.0)
+    actionpack (5.2.2.1)
+      actionview (= 5.2.2.1)
+      activesupport (= 5.2.2.1)
+      rack (~> 2.0)
+      rack-test (>= 0.6.3)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.0.2)
+    actionview (5.2.2.1)
+      activesupport (= 5.2.2.1)
+      builder (~> 3.1)
+      erubi (~> 1.4)
+      rails-dom-testing (~> 2.0)
+      rails-html-sanitizer (~> 1.0, >= 1.0.3)
+    activejob (5.2.2.1)
+      activesupport (= 5.2.2.1)
+      globalid (>= 0.3.6)
+    activemodel (5.2.2.1)
+      activesupport (= 5.2.2.1)
+    activerecord (5.2.2.1)
+      activemodel (= 5.2.2.1)
+      activesupport (= 5.2.2.1)
+      arel (>= 9.0)
+    activestorage (5.2.2.1)
+      actionpack (= 5.2.2.1)
+      activerecord (= 5.2.2.1)
+      marcel (~> 0.3.1)
+    activesupport (5.2.2.1)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 0.7, < 2)
+      minitest (~> 5.1)
+      tzinfo (~> 1.1)
+    addressable (2.6.0)
+      public_suffix (>= 2.0.2, < 4.0)
+    archive-zip (0.12.0)
+      io-like (~> 0.3.0)
+    arel (9.0.0)
+    bcrypt (3.1.12)
+    bindex (0.5.0)
+    bootsnap (1.4.1)
+      msgpack (~> 1.0)
+    builder (3.2.3)
+    byebug (11.0.1)
+    capybara (3.15.0)
+      addressable
+      mini_mime (>= 0.1.3)
+      nokogiri (~> 1.8)
+      rack (>= 1.6.0)
+      rack-test (>= 0.6.3)
+      regexp_parser (~> 1.2)
+      xpath (~> 3.2)
+    childprocess (0.9.0)
+      ffi (~> 1.0, >= 1.0.11)
+    chromedriver-helper (2.1.0)
+      archive-zip (~> 0.10)
+      nokogiri (~> 1.8)
+    coffee-rails (4.2.2)
+      coffee-script (>= 2.2.0)
+      railties (>= 4.0.0)
+    coffee-script (2.4.1)
+      coffee-script-source
+      execjs
+    coffee-script-source (1.12.2)
+    concurrent-ruby (1.1.5)
+    crass (1.0.4)
+    devise (4.6.1)
+      bcrypt (~> 3.0)
+      orm_adapter (~> 0.1)
+      railties (>= 4.1.0, < 6.0)
+      responders
+      warden (~> 1.2.3)
+    equatable (0.5.0)
+    erubi (1.8.0)
+    execjs (2.7.0)
+    ffi (1.10.0)
+    globalid (0.4.2)
+      activesupport (>= 4.2.0)
+    i18n (1.6.0)
+      concurrent-ruby (~> 1.0)
+    io-like (0.3.0)
+    jbuilder (2.8.0)
+      activesupport (>= 4.2.0)
+      multi_json (>= 1.2)
+    listen (3.1.5)
+      rb-fsevent (~> 0.9, >= 0.9.4)
+      rb-inotify (~> 0.9, >= 0.9.7)
+      ruby_dep (~> 1.2)
+    loofah (2.2.3)
+      crass (~> 1.0.2)
+      nokogiri (>= 1.5.9)
+    mail (2.7.1)
+      mini_mime (>= 0.1.1)
+    marcel (0.3.3)
+      mimemagic (~> 0.3.2)
+    method_source (0.9.2)
+    mimemagic (0.3.3)
+    mini_mime (1.0.1)
+    mini_portile2 (2.4.0)
+    minitest (5.11.3)
+    msgpack (1.2.9)
+    multi_json (1.13.1)
+    nio4r (2.3.1)
+    nokogiri (1.10.1)
+      mini_portile2 (~> 2.4.0)
+    orm_adapter (0.5.0)
+    pastel (0.7.2)
+      equatable (~> 0.5.0)
+      tty-color (~> 0.4.0)
+    pg (1.1.4)
+    public_suffix (3.0.3)
+    puma (3.12.1)
+    rack (2.0.6)
+    rack-test (1.1.0)
+      rack (>= 1.0, < 3)
+    rails (5.2.2.1)
+      actioncable (= 5.2.2.1)
+      actionmailer (= 5.2.2.1)
+      actionpack (= 5.2.2.1)
+      actionview (= 5.2.2.1)
+      activejob (= 5.2.2.1)
+      activemodel (= 5.2.2.1)
+      activerecord (= 5.2.2.1)
+      activestorage (= 5.2.2.1)
+      activesupport (= 5.2.2.1)
+      bundler (>= 1.3.0)
+      railties (= 5.2.2.1)
+      sprockets-rails (>= 2.0.0)
+    rails-dom-testing (2.0.3)
+      activesupport (>= 4.2.0)
+      nokogiri (>= 1.6)
+    rails-html-sanitizer (1.0.4)
+      loofah (~> 2.2, >= 2.2.2)
+    railties (5.2.2.1)
+      actionpack (= 5.2.2.1)
+      activesupport (= 5.2.2.1)
+      method_source
+      rake (>= 0.8.7)
+      thor (>= 0.19.0, < 2.0)
+    rake (12.3.2)
+    rb-fsevent (0.10.3)
+    rb-inotify (0.10.0)
+      ffi (~> 1.0)
+    regexp_parser (1.3.0)
+    responders (2.4.1)
+      actionpack (>= 4.2.0, < 6.0)
+      railties (>= 4.2.0, < 6.0)
+    ruby_dep (1.5.0)
+    rubyzip (1.2.2)
+    sass (3.7.3)
+      sass-listen (~> 4.0.0)
+    sass-listen (4.0.0)
+      rb-fsevent (~> 0.9, >= 0.9.4)
+      rb-inotify (~> 0.9, >= 0.9.7)
+    sass-rails (5.0.7)
+      railties (>= 4.0.0, < 6)
+      sass (~> 3.1)
+      sprockets (>= 2.8, < 4.0)
+      sprockets-rails (>= 2.0, < 4.0)
+      tilt (>= 1.1, < 3)
+    selenium-webdriver (3.141.0)
+      childprocess (~> 0.5)
+      rubyzip (~> 1.2, >= 1.2.2)
+    spring (2.0.2)
+      activesupport (>= 4.2)
+    spring-watcher-listen (2.0.1)
+      listen (>= 2.7, < 4.0)
+      spring (>= 1.2, < 3.0)
+    sprockets (3.7.2)
+      concurrent-ruby (~> 1.0)
+      rack (> 1, < 3)
+    sprockets-rails (3.2.1)
+      actionpack (>= 4.0)
+      activesupport (>= 4.0)
+      sprockets (>= 3.0.0)
+    strings (0.1.4)
+      strings-ansi (~> 0.1.0)
+      unicode-display_width (~> 1.4.0)
+      unicode_utils (~> 1.4.0)
+    strings-ansi (0.1.0)
+    thor (0.20.3)
+    thread_safe (0.3.6)
+    tilt (2.0.9)
+    tty-color (0.4.3)
+    tty-pager (0.12.1)
+      strings (~> 0.1.4)
+      tty-screen (~> 0.6)
+      tty-which (~> 0.4)
+    tty-screen (0.6.5)
+    tty-tree (0.2.0)
+    tty-which (0.4.0)
+    turbolinks (5.2.0)
+      turbolinks-source (~> 5.2)
+    turbolinks-source (5.2.0)
+    tzinfo (1.2.5)
+      thread_safe (~> 0.1)
+    uglifier (4.1.20)
+      execjs (>= 0.3.0, < 3)
+    unicode-display_width (1.4.1)
+    unicode_utils (1.4.0)
+    warden (1.2.8)
+      rack (>= 2.0.6)
+    web-console (3.7.0)
+      actionview (>= 5.0)
+      activemodel (>= 5.0)
+      bindex (>= 0.4.0)
+      railties (>= 5.0)
+    websocket-driver (0.7.0)
+      websocket-extensions (>= 0.1.0)
+    websocket-extensions (0.1.3)
+    xpath (3.2.0)
+      nokogiri (~> 1.8)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  bootsnap (>= 1.1.0)
+  byebug
+  capybara (>= 2.15)
+  chromedriver-helper
+  coffee-rails (~> 4.2)
+  devise
+  faker!
+  jbuilder (~> 2.5)
+  listen (>= 3.0.5, < 3.2)
+  pg (>= 0.18, < 2.0)
+  puma (~> 3.11)
+  rails (~> 5.2.2, >= 5.2.2.1)
+  sass-rails (~> 5.0)
+  selenium-webdriver
+  spring
+  spring-watcher-listen (~> 2.0.0)
+  turbolinks (~> 5)
+  tzinfo-data
+  uglifier (>= 1.3.0)
+  web-console (>= 3.3.0)
+
+RUBY VERSION
+   ruby 2.5.5p157
+
+BUNDLED WITH
+   1.17.3
--- a/example/README.md
+++ b/example/README.md
@ -0,0 +1,24 @@
+# README
+
+This README would normally document whatever steps are necessary to get the
+application up and running.
+
+Things you may want to cover:
+
+* Ruby version
+
+* System dependencies
+
+* Configuration
+
+* Database creation
+
+* Database initialization
+
+* How to run the test suite
+
+* Services (job queues, cache servers, search engines, etc.)
+
+* Deployment instructions
+
+* ...
--- a/example/Rakefile
+++ b/example/Rakefile
@ -0,0 +1,6 @@
+# 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'
+
+Rails.application.load_tasks
--- a/example/app/assets/config/manifest.js
+++ b/example/app/assets/config/manifest.js
@ -0,0 +1,3 @@
+//= link_tree ../images
+//= link_directory ../javascripts .js
+//= link_directory ../stylesheets .css
--- a/example/app/assets/images/.keep
+++ b/example/app/assets/images/.keep
--- a/example/app/assets/javascripts/application.js
+++ b/example/app/assets/javascripts/application.js
@ -0,0 +1,16 @@
+// This is a manifest file that'll be compiled into application.js, which will include all the files
+// listed below.
+//
+// Any JavaScript/Coffee file within this directory, lib/assets/javascripts, or any plugin's
+// vendor/assets/javascripts directory can be referenced here using a relative path.
+//
+// It's not advisable to add code directly here, but if you do, it'll appear at the bottom of the
+// compiled file. JavaScript code in this file should be added after the last require_* statement.
+//
+// Read Sprockets README (https://github.com/rails/sprockets#sprockets-directives) for details
+// about supported directives.
+//
+//= require rails-ujs
+//= require activestorage
+//= require turbolinks
+//= require_tree .
--- a/example/app/assets/javascripts/cable.js
+++ b/example/app/assets/javascripts/cable.js
@ -0,0 +1,13 @@
+// Action Cable provides the framework to deal with WebSockets in Rails.
+// You can generate new channels where WebSocket features live using the `rails generate channel` command.
+//
+//= require action_cable
+//= require_self
+//= require_tree ./channels
+
+(function() {
+  this.App || (this.App = {});
+
+  App.cable = ActionCable.createConsumer();
+
+}).call(this);
--- a/example/app/assets/javascripts/channels/.keep
+++ b/example/app/assets/javascripts/channels/.keep
--- a/example/app/assets/javascripts/products.coffee
+++ b/example/app/assets/javascripts/products.coffee
@ -0,0 +1,3 @@
+# Place all the behaviors and hooks related to the matching controller here.
+# All this logic will automatically be available in application.js.
+# You can use CoffeeScript in this file: http://coffeescript.org/
--- a/example/app/assets/stylesheets/application.css
+++ b/example/app/assets/stylesheets/application.css
@ -0,0 +1,15 @@
+/*
+ * This is a manifest file that'll be compiled into application.css, which will include all the files
+ * listed below.
+ *
+ * Any CSS and SCSS file within this directory, lib/assets/stylesheets, or any plugin's
+ * vendor/assets/stylesheets directory can be referenced here using a relative path.
+ *
+ * You're free to add application-wide styles to this file and they'll appear at the bottom of the
+ * compiled file so the styles you add here take precedence over styles defined in any other CSS/SCSS
+ * files in this directory. Styles in this file should be added after the last require_* statement.
+ * It is generally better to create a new file per style scope.
+ *
+ *= require_tree .
+ *= require_self
+ */
--- a/example/app/assets/stylesheets/products.scss
+++ b/example/app/assets/stylesheets/products.scss
@ -0,0 +1,3 @@
+// Place all the styles related to the products controller here.
+// They will automatically be included in application.css.
+// You can use Sass (SCSS) here: http://sass-lang.com/
--- a/example/app/assets/stylesheets/scaffolds.scss
+++ b/example/app/assets/stylesheets/scaffolds.scss
@ -0,0 +1,84 @@
+body {
+  background-color: #fff;
+  color: #333;
+  margin: 33px;
+  font-family: verdana, arial, helvetica, sans-serif;
+  font-size: 13px;
+  line-height: 18px;
+}
+
+p, ol, ul, td {
+  font-family: verdana, arial, helvetica, sans-serif;
+  font-size: 13px;
+  line-height: 18px;
+}
+
+pre {
+  background-color: #eee;
+  padding: 10px;
+  font-size: 11px;
+}
+
+a {
+  color: #000;
+
+  &:visited {
+    color: #666;
+  }
+
+  &:hover {
+    color: #fff;
+    background-color: #000;
+  }
+}
+
+th {
+  padding-bottom: 5px;
+}
+
+td {
+  padding: 0 5px 7px;
+}
+
+div {
+  &.field, &.actions {
+    margin-bottom: 10px;
+  }
+}
+
+#notice {
+  color: green;
+}
+
+.field_with_errors {
+  padding: 2px;
+  background-color: red;
+  display: table;
+}
+
+#error_explanation {
+  width: 450px;
+  border: 2px solid red;
+  padding: 7px 7px 0;
+  margin-bottom: 20px;
+  background-color: #f0f0f0;
+
+  h2 {
+    text-align: left;
+    font-weight: bold;
+    padding: 5px 5px 5px 15px;
+    font-size: 12px;
+    margin: -7px -7px 0;
+    background-color: #c00;
+    color: #fff;
+  }
+
+  ul li {
+    font-size: 12px;
+    list-style: square;
+  }
+}
+
+label {
+  display: block;
+}
--- a/example/app/channels/application_cable/channel.rb
+++ b/example/app/channels/application_cable/channel.rb
@ -0,0 +1,4 @@
+module ApplicationCable
+  class Channel < ActionCable::Channel::Base
+  end
+end
--- a/example/app/channels/application_cable/connection.rb
+++ b/example/app/channels/application_cable/connection.rb
@ -0,0 +1,4 @@
+module ApplicationCable
+  class Connection < ActionCable::Connection::Base
+  end
+end
--- a/example/app/controllers/application_controller.rb
+++ b/example/app/controllers/application_controller.rb
@ -0,0 +1,3 @@
+class ApplicationController < ActionController::Base
+  before_action :authenticate_user!
+end
--- a/example/app/controllers/concerns/.keep
+++ b/example/app/controllers/concerns/.keep
--- a/example/app/controllers/products_controller.rb
+++ b/example/app/controllers/products_controller.rb
@ -0,0 +1,74 @@
+class ProductsController < ApplicationController
+  before_action :set_product, only: [:show, :edit, :update, :destroy]
+
+  # GET /products
+  # GET /products.json
+  def index
+    @products = Product.all
+  end
+
+  # GET /products/1
+  # GET /products/1.json
+  def show
+  end
+
+  # GET /products/new
+  def new
+    @product = Product.new
+  end
+
+  # GET /products/1/edit
+  def edit
+  end
+
+  # POST /products
+  # POST /products.json
+  def create
+    @product = Product.new(product_params)
+
+    respond_to do |format|
+      if @product.save
+        format.html { redirect_to @product, notice: 'Product was successfully created.' }
+        format.json { render :show, status: :created, location: @product }
+      else
+        format.html { render :new }
+        format.json { render json: @product.errors, status: :unprocessable_entity }
+      end
+    end
+  end
+
+  # PATCH/PUT /products/1
+  # PATCH/PUT /products/1.json
+  def update
+    respond_to do |format|
+      if @product.update(product_params)
+        format.html { redirect_to @product, notice: 'Product was successfully updated.' }
+        format.json { render :show, status: :ok, location: @product }
+      else
+        format.html { render :edit }
+        format.json { render json: @product.errors, status: :unprocessable_entity }
+      end
+    end
+  end
+
+  # DELETE /products/1
+  # DELETE /products/1.json
+  def destroy
+    @product.destroy
+    respond_to do |format|
+      format.html { redirect_to products_url, notice: 'Product was successfully destroyed.' }
+      format.json { head :no_content }
+    end
+  end
+
+  private
+    # Use callbacks to share common setup or constraints between actions.
+    def set_product
+      @product = Product.find(params[:id])
+    end
+
+    # Never trust parameters from the scary internet, only allow the white list through.
+    def product_params
+      params.require(:product).permit(:name, :description, :price)
+    end
+end
--- a/example/app/helpers/application_helper.rb
+++ b/example/app/helpers/application_helper.rb
@ -0,0 +1,2 @@
+module ApplicationHelper
+end
--- a/example/app/helpers/products_helper.rb
+++ b/example/app/helpers/products_helper.rb
@ -0,0 +1,2 @@
+module ProductsHelper
+end
--- a/example/app/jobs/application_job.rb
+++ b/example/app/jobs/application_job.rb
@ -0,0 +1,2 @@
+class ApplicationJob < ActiveJob::Base
+end
--- a/example/app/mailers/application_mailer.rb
+++ b/example/app/mailers/application_mailer.rb
@ -0,0 +1,4 @@
+class ApplicationMailer < ActionMailer::Base
+  default from: 'from@example.com'
+  layout 'mailer'
+end
--- a/example/app/models/application_record.rb
+++ b/example/app/models/application_record.rb
@ -0,0 +1,3 @@
+class ApplicationRecord < ActiveRecord::Base
+  self.abstract_class = true
+end
--- a/example/app/models/concerns/.keep
+++ b/example/app/models/concerns/.keep
--- a/example/app/models/customer.rb
+++ b/example/app/models/customer.rb
@ -0,0 +1,8 @@
+class Customer < ApplicationRecord
+  # Include default devise modules. Others available are:
+  # :confirmable, :lockable, :timeoutable, :trackable and :omniauthable
+  devise :database_authenticatable, :registerable,
+         :recoverable, :rememberable, :validatable
+
+  has_many :products, through: :purchases
+end
--- a/example/app/models/product.rb
+++ b/example/app/models/product.rb
@ -0,0 +1,3 @@
+class Product < ApplicationRecord
+  has_many :customers, through: :purchases
+end
--- a/example/app/models/purchase.rb
+++ b/example/app/models/purchase.rb
@ -0,0 +1,4 @@
+class Purchase < ApplicationRecord
+  validates :sale_type, :inclusion => { :in => %w{rented bought} }
+  validates :quantity, numericality: { greater_than: 0 }
+end
--- a/example/app/models/user.rb
+++ b/example/app/models/user.rb
@ -0,0 +1,8 @@
+class User < ApplicationRecord
+  # Include default devise modules. Others available are:
+  # :confirmable, :lockable, :timeoutable, :trackable and :omniauthable
+  devise :database_authenticatable, :registerable,
+         :recoverable, :rememberable, :validatable
+  
+  has_many :products
+end
--- a/example/app/views/layouts/application.html.erb
+++ b/example/app/views/layouts/application.html.erb
@ -0,0 +1,15 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>App</title>
+    <%= csrf_meta_tags %>
+    <%= csp_meta_tag %>
+
+    <%= stylesheet_link_tag    'application', media: 'all', 'data-turbolinks-track': 'reload' %>
+    <%= javascript_include_tag 'application', 'data-turbolinks-track': 'reload' %>
+  </head>
+
+  <body>
+    <%= yield %>
+  </body>
+</html>
--- a/example/app/views/layouts/mailer.html.erb
+++ b/example/app/views/layouts/mailer.html.erb
@ -0,0 +1,13 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
+    <style>
+      /* Email styles need to be inline */
+    </style>
+  </head>
+
+  <body>
+    <%= yield %>
+  </body>
+</html>
--- a/example/app/views/layouts/mailer.text.erb
+++ b/example/app/views/layouts/mailer.text.erb
@ -0,0 +1 @@
+<%= yield %>
--- a/example/app/views/products/_form.html.erb
+++ b/example/app/views/products/_form.html.erb
@ -0,0 +1,32 @@
+<%= form_with(model: product, local: true) do |form| %>
+  <% if product.errors.any? %>
+    <div id="error_explanation">
+      <h2><%= pluralize(product.errors.count, "error") %> prohibited this product from being saved:</h2>
+
+      <ul>
+      <% product.errors.full_messages.each do |message| %>
+        <li><%= message %></li>
+      <% end %>
+      </ul>
+    </div>
+  <% end %>
+
+  <div class="field">
+    <%= form.label :name %>
+    <%= form.text_field :name %>
+  </div>
+
+  <div class="field">
+    <%= form.label :description %>
+    <%= form.text_area :description %>
+  </div>
+
+  <div class="field">
+    <%= form.label :price %>
+    <%= form.text_field :price %>
+  </div>
+
+  <div class="actions">
+    <%= form.submit %>
+  </div>
+<% end %>
--- a/example/app/views/products/_product.json.jbuilder
+++ b/example/app/views/products/_product.json.jbuilder
@ -0,0 +1,2 @@
+json.extract! product, :id, :name, :description, :price, :created_at, :updated_at
+json.url product_url(product, format: :json)
--- a/example/app/views/products/edit.html.erb
+++ b/example/app/views/products/edit.html.erb
@ -0,0 +1,6 @@
+<h1>Editing Product</h1>
+
+<%= render 'form', product: @product %>
+
+<%= link_to 'Show', @product %> |
+<%= link_to 'Back', products_path %>
--- a/example/app/views/products/index.html.erb
+++ b/example/app/views/products/index.html.erb
@ -0,0 +1,31 @@
+<p id="notice"><%= notice %></p>
+
+<h1>Products</h1>
+
+<table>
+  <thead>
+    <tr>
+      <th>Name</th>
+      <th>Description</th>
+      <th>Price</th>
+      <th colspan="3"></th>
+    </tr>
+  </thead>
+
+  <tbody>
+    <% @products.each do |product| %>
+      <tr>
+        <td><%= product.name %></td>
+        <td><%= product.description %></td>
+        <td><%= product.price %></td>
+        <td><%= link_to 'Show', product %></td>
+        <td><%= link_to 'Edit', edit_product_path(product) %></td>
+        <td><%= link_to 'Destroy', product, method: :delete, data: { confirm: 'Are you sure?' } %></td>
+      </tr>
+    <% end %>
+  </tbody>
+</table>
+
+<br>
+
+<%= link_to 'New Product', new_product_path %>
--- a/example/app/views/products/index.json.jbuilder
+++ b/example/app/views/products/index.json.jbuilder
@ -0,0 +1 @@
+json.array! @products, partial: 'products/product', as: :product
--- a/example/app/views/products/new.html.erb
+++ b/example/app/views/products/new.html.erb
@ -0,0 +1,5 @@
+<h1>New Product</h1>
+
+<%= render 'form', product: @product %>
+
+<%= link_to 'Back', products_path %>
--- a/example/app/views/products/show.html.erb
+++ b/example/app/views/products/show.html.erb
@ -0,0 +1,19 @@
+<p id="notice"><%= notice %></p>
+
+<p>
+  <strong>Name:</strong>
+  <%= @product.name %>
+</p>
+
+<p>
+  <strong>Description:</strong>
+  <%= @product.description %>
+</p>
+
+<p>
+  <strong>Price:</strong>
+  <%= @product.price %>
+</p>
+
+<%= link_to 'Edit', edit_product_path(@product) %> |
+<%= link_to 'Back', products_path %>
--- a/example/app/views/products/show.json.jbuilder
+++ b/example/app/views/products/show.json.jbuilder
@ -0,0 +1 @@
+json.partial! "products/product", product: @product
--- a/example/bin/bundle
+++ b/example/bin/bundle
@ -0,0 +1,3 @@
+#!/usr/bin/env ruby
+ENV['BUNDLE_GEMFILE'] ||= File.expand_path('../Gemfile', __dir__)
+load Gem.bin_path('bundler', 'bundle')
--- a/example/bin/rails
+++ b/example/bin/rails
@ -0,0 +1,9 @@
+#!/usr/bin/env ruby
+begin
+  load File.expand_path('../spring', __FILE__)
+rescue LoadError => e
+  raise unless e.message.include?('spring')
+end
+APP_PATH = File.expand_path('../config/application', __dir__)
+require_relative '../config/boot'
+require 'rails/commands'
--- a/example/bin/rake
+++ b/example/bin/rake
@ -0,0 +1,9 @@
+#!/usr/bin/env ruby
+begin
+  load File.expand_path('../spring', __FILE__)
+rescue LoadError => e
+  raise unless e.message.include?('spring')
+end
+require_relative '../config/boot'
+require 'rake'
+Rake.application.run
--- a/example/bin/setup
+++ b/example/bin/setup
@ -0,0 +1,36 @@
+#!/usr/bin/env ruby
+require 'fileutils'
+include FileUtils
+
+# path to your application root.
+APP_ROOT = File.expand_path('..', __dir__)
+
+def system!(*args)
+  system(*args) || abort("\n== Command #{args} failed ==")
+end
+
+chdir APP_ROOT do
+  # This script is a starting point to setup your application.
+  # Add necessary setup steps to this file.
+
+  puts '== Installing dependencies =='
+  system! 'gem install bundler --conservative'
+  system('bundle check') || system!('bundle install')
+
+  # Install JavaScript dependencies if using Yarn
+  # system('bin/yarn')
+
+  # puts "\n== Copying sample files =="
+  # unless File.exist?('config/database.yml')
+  #   cp 'config/database.yml.sample', 'config/database.yml'
+  # end
+
+  puts "\n== Preparing database =="
+  system! 'bin/rails db:setup'
+
+  puts "\n== Removing old logs and tempfiles =="
+  system! 'bin/rails log:clear tmp:clear'
+
+  puts "\n== Restarting application server =="
+  system! 'bin/rails restart'
+end
--- a/example/bin/spring
+++ b/example/bin/spring
@ -0,0 +1,17 @@
+#!/usr/bin/env ruby
+
+# This file loads spring without using Bundler, in order to be fast.
+# It gets overwritten when you run the `spring binstub` command.
+
+unless defined?(Spring)
+  require 'rubygems'
+  require 'bundler'
+
+  lockfile = Bundler::LockfileParser.new(Bundler.default_lockfile.read)
+  spring = lockfile.specs.detect { |spec| spec.name == "spring" }
+  if spring
+    Gem.use_paths Gem.dir, Bundler.bundle_path.to_s, *Gem.path
+    gem 'spring', spring.version
+    require 'spring/binstub'
+  end
+end
--- a/example/bin/update
+++ b/example/bin/update
@ -0,0 +1,31 @@
+#!/usr/bin/env ruby
+require 'fileutils'
+include FileUtils
+
+# path to your application root.
+APP_ROOT = File.expand_path('..', __dir__)
+
+def system!(*args)
+  system(*args) || abort("\n== Command #{args} failed ==")
+end
+
+chdir APP_ROOT do
+  # This script is a way to update your development environment automatically.
+  # Add necessary update steps to this file.
+
+  puts '== Installing dependencies =='
+  system! 'gem install bundler --conservative'
+  system('bundle check') || system!('bundle install')
+
+  # Install JavaScript dependencies if using Yarn
+  # system('bin/yarn')
+
+  puts "\n== Updating database =="
+  system! 'bin/rails db:migrate'
+
+  puts "\n== Removing old logs and tempfiles =="
+  system! 'bin/rails log:clear tmp:clear'
+
+  puts "\n== Restarting application server =="
+  system! 'bin/rails restart'
+end
--- a/example/bin/yarn
+++ b/example/bin/yarn
@ -0,0 +1,11 @@
+#!/usr/bin/env ruby
+APP_ROOT = File.expand_path('..', __dir__)
+Dir.chdir(APP_ROOT) do
+  begin
+    exec "yarnpkg", *ARGV
+  rescue Errno::ENOENT
+    $stderr.puts "Yarn executable was not detected in the system."
+    $stderr.puts "Download Yarn at https://yarnpkg.com/en/docs/install"
+    exit 1
+  end
+end
--- a/example/config.ru
+++ b/example/config.ru
@ -0,0 +1,5 @@
+# This file is used by Rack-based servers to start the application.
+
+require_relative 'config/environment'
+
+run Rails.application
--- a/example/config/application.rb
+++ b/example/config/application.rb
@ -0,0 +1,19 @@
+require_relative 'boot'
+
+require 'rails/all'
+
+# Require the gems listed in Gemfile, including any gems
+# you've limited to :test, :development, or :production.
+Bundler.require(*Rails.groups)
+
+module App
+  class Application < Rails::Application
+    # Initialize configuration defaults for originally generated Rails version.
+    config.load_defaults 5.2
+
+    # Settings in config/environments/* take precedence over those specified here.
+    # Application configuration can go into files in config/initializers
+    # -- all .rb files in that directory are automatically loaded after loading
+    # the framework and any gems in your application.
+  end
+end
--- a/example/config/boot.rb
+++ b/example/config/boot.rb
@ -0,0 +1,4 @@
+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.
--- a/example/config/cable.yml
+++ b/example/config/cable.yml
@ -0,0 +1,10 @@
+development:
+  adapter: async
+
+test:
+  adapter: async
+
+production:
+  adapter: redis
+  url: <%= ENV.fetch("REDIS_URL") { "redis://localhost:6379/1" } %>
+  channel_prefix: app_production
--- a/example/config/credentials.yml.enc
+++ b/example/config/credentials.yml.enc
@ -0,0 +1 @@
+ze/YtOkYCXCK6/Rd4s3aPDyKyUvhbe5FnZR47QG38a2bfQ/9SjQ9eI44fJcTamD3YegF2WfChuWHOfrxQHZqg9d2MKhSzXtBOfNL9Ym1cgLkhGjoxBUoEvKPZHeMW5RMHOnpzyVexvt3Yho5XSdNta7ic6oQBGRSPNUF5OB1G2Kcu6PtIBD7d7X2GQcjzVpsh8IXEK63HQ7lsywK3RSy2DqkkioH3ZOHZgd4xUKCofhiMxe7sxqo9nid+zKiqGnjnnKQ4ferXqCyF/wIRwTbD5kZ/w0yohsq8afVZJEQ9x5ZmPB09x/S5j3Wv87MpBFpHYWh/W7A0Ede+zJE9dyJRlRFaipclA1c0R2wrL0xeTcoA3U1pyRDKxaIU/0AYaxJ3ShNRy3rsDFtqvSlfGuHh4zGYDBk2dZ+NeLU--7folMaIoT99K7IAL--5XdEoGfrgiSYInpqOpRR+w==
--- a/example/config/database.yml
+++ b/example/config/database.yml
@ -0,0 +1,86 @@
+# PostgreSQL. Versions 9.1 and up are supported.
+#
+# Install the pg driver:
+#   gem install pg
+# On OS X with Homebrew:
+#   gem install pg -- --with-pg-config=/usr/local/bin/pg_config
+# On OS X 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: postgresql
+  encoding: unicode
+  host: db
+  username: postgres
+  password:
+  pool: 5
+
+development:
+  <<: *default
+  database: 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 that initialized the database.
+  #username: app
+
+  # The password associated with the postgres role (username).
+  #password:
+
+  # 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: app_test
+
+# As with config/secrets.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 as a unix environment variable when you boot
+# the app. Read http://guides.rubyonrails.org/configuring.html#configuring-a-database
+# for a full rundown on how to provide these environment variables in a
+# production deployment.
+#
+# On Heroku and other platform providers, you may have a full connection URL
+# available as an environment variable. For example:
+#
+#   DATABASE_URL="postgres://myuser:mypass@localhost/somedatabase"
+#
+# You can use this database configuration with:
+#
+#   production:
+#     url: <%= ENV['DATABASE_URL'] %>
+#
+production:
+  <<: *default
+  database: app_production
+  username: app
+  password: <%= ENV['APP_DATABASE_PASSWORD'] %>
--- a/example/config/environment.rb
+++ b/example/config/environment.rb
@ -0,0 +1,5 @@
+# Load the Rails application.
+require_relative 'application'
+
+# Initialize the Rails application.
+Rails.application.initialize!
--- a/example/config/environments/development.rb
+++ b/example/config/environments/development.rb
@ -0,0 +1,63 @@
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # In the development environment your application's code is reloaded on
+  # every request. This slows down response time but is perfect for development
+  # since you don't have to restart the web server when you make code changes.
+  config.cache_classes = false
+
+  # Do not eager load code on boot.
+  config.eager_load = false
+
+  # Show full error reports.
+  config.consider_all_requests_local = true
+
+  # Enable/disable caching. By default caching is disabled.
+  # Run rails dev:cache to toggle caching.
+  if Rails.root.join('tmp', 'caching-dev.txt').exist?
+    config.action_controller.perform_caching = true
+
+    config.cache_store = :memory_store
+    config.public_file_server.headers = {
+      'Cache-Control' => "public, max-age=#{2.days.to_i}"
+    }
+  else
+    config.action_controller.perform_caching = false
+
+    config.cache_store = :null_store
+  end
+
+  # Store uploaded files on the local file system (see config/storage.yml for options)
+  config.active_storage.service = :local
+
+  # Don't care if the mailer can't send.
+  config.action_mailer.raise_delivery_errors = false
+
+  config.action_mailer.perform_caching = false
+
+  # Print deprecation notices to the Rails logger.
+  config.active_support.deprecation = :log
+
+  # Raise an error on page load if there are pending migrations.
+  config.active_record.migration_error = :page_load
+
+  # Highlight code that triggered database queries in logs.
+  config.active_record.verbose_query_logs = true
+
+  # Debug mode disables concatenation and preprocessing of assets.
+  # This option may cause significant delays in view rendering with a large
+  # number of complex assets.
+  config.assets.debug = true
+
+  # Suppress logger output for asset requests.
+  config.assets.quiet = true
+
+  # Raises error for missing translations
+  # config.action_view.raise_on_missing_translations = true
+
+  # Use an evented file watcher to asynchronously detect changes in source code,
+  # routes, locales, etc. This feature depends on the listen gem.
+  config.file_watcher = ActiveSupport::EventedFileUpdateChecker
+
+  config.action_mailer.default_url_options = { host: 'localhost', port: 3000 }
+end
--- a/example/config/environments/production.rb
+++ b/example/config/environments/production.rb
@ -0,0 +1,94 @@
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # Code is not reloaded between requests.
+  config.cache_classes = true
+
+  # Eager load code on boot. This eager loads most of Rails and
+  # your application in memory, allowing both threaded web servers
+  # and those relying on copy on write to perform better.
+  # Rake tasks automatically ignore this option for performance.
+  config.eager_load = true
+
+  # Full error reports are disabled and caching is turned on.
+  config.consider_all_requests_local       = false
+  config.action_controller.perform_caching = true
+
+  # 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).
+  # config.require_master_key = true
+
+  # 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?
+
+  # Compress JavaScripts and CSS.
+  config.assets.js_compressor = :uglifier
+  # config.assets.css_compressor = :sass
+
+  # Do not fallback to assets pipeline if a precompiled asset is missed.
+  config.assets.compile = false
+
+  # `config.assets.precompile` and `config.assets.version` have moved to config/initializers/assets.rb
+
+  # Enable serving of images, stylesheets, and JavaScripts from an asset server.
+  # config.action_controller.asset_host = 'http://assets.example.com'
+
+  # Specifies the header that your server uses for sending files.
+  # config.action_dispatch.x_sendfile_header = 'X-Sendfile' # for Apache
+  # config.action_dispatch.x_sendfile_header = 'X-Accel-Redirect' # for NGINX
+
+  # Store uploaded files on the local file system (see config/storage.yml for options)
+  config.active_storage.service = :local
+
+  # Mount Action Cable outside main process or domain
+  # config.action_cable.mount_path = nil
+  # config.action_cable.url = 'wss://example.com/cable'
+  # config.action_cable.allowed_request_origins = [ 'http://example.com', /http:\/\/example.*/ ]
+
+  # Force all access to the app over SSL, use Strict-Transport-Security, and use secure cookies.
+  # config.force_ssl = true
+
+  # Use the lowest log level to ensure availability of diagnostic information
+  # when problems arise.
+  config.log_level = :debug
+
+  # Prepend all log lines with the following tags.
+  config.log_tags = [ :request_id ]
+
+  # Use a different cache store in production.
+  # config.cache_store = :mem_cache_store
+
+  # Use a real queuing backend for Active Job (and separate queues per environment)
+  # config.active_job.queue_adapter     = :resque
+  # config.active_job.queue_name_prefix = "app_#{Rails.env}"
+
+  config.action_mailer.perform_caching = false
+
+  # Ignore bad email addresses and do not raise email delivery errors.
+  # Set this to true and configure the email server for immediate delivery to raise delivery errors.
+  # config.action_mailer.raise_delivery_errors = false
+
+  # Enable locale fallbacks for I18n (makes lookups for any locale fall back to
+  # the I18n.default_locale when a translation cannot be found).
+  config.i18n.fallbacks = true
+
+  # Send deprecation notices to registered listeners.
+  config.active_support.deprecation = :notify
+
+  # Use default logging formatter so that PID and timestamp are not suppressed.
+  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)
+    logger.formatter = config.log_formatter
+    config.logger    = ActiveSupport::TaggedLogging.new(logger)
+  end
+
+  # Do not dump schema after migrations.
+  config.active_record.dump_schema_after_migration = false
+end
--- a/example/config/environments/test.rb
+++ b/example/config/environments/test.rb
@ -0,0 +1,46 @@
+Rails.application.configure do
+  # Settings specified here will take precedence over those in config/application.rb.
+
+  # The test environment is used exclusively to run your application's
+  # test suite. You never need to work with it otherwise. Remember that
+  # your test database is "scratch space" for the test suite and is wiped
+  # and recreated between test runs. Don't rely on the data there!
+  config.cache_classes = true
+
+  # Do not eager load code on boot. This avoids loading your whole application
+  # just for the purpose of running a single test. If you are using a tool that
+  # preloads Rails for running tests, you may have to set it to true.
+  config.eager_load = false
+
+  # 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}"
+  }
+
+  # Show full error reports and disable caching.
+  config.consider_all_requests_local       = true
+  config.action_controller.perform_caching = false
+
+  # Raise exceptions instead of rendering exception templates.
+  config.action_dispatch.show_exceptions = false
+
+  # Disable request forgery protection in test environment.
+  config.action_controller.allow_forgery_protection = false
+
+  # Store uploaded files on the local file system in a temporary directory
+  config.active_storage.service = :test
+
+  config.action_mailer.perform_caching = false
+
+  # Tell Action Mailer not to deliver emails to the real world.
+  # The :test delivery method accumulates sent emails in the
+  # ActionMailer::Base.deliveries array.
+  config.action_mailer.delivery_method = :test
+
+  # Print deprecation notices to the stderr.
+  config.active_support.deprecation = :stderr
+
+  # Raises error for missing translations
+  # config.action_view.raise_on_missing_translations = true
+end
--- a/example/config/initializers/application_controller_renderer.rb
+++ b/example/config/initializers/application_controller_renderer.rb
@ -0,0 +1,8 @@
+# Be sure to restart your server when you modify this file.
+
+# ActiveSupport::Reloader.to_prepare do
+#   ApplicationController.renderer.defaults.merge!(
+#     http_host: 'example.org',
+#     https: false
+#   )
+# end
--- a/example/config/initializers/assets.rb
+++ b/example/config/initializers/assets.rb
@ -0,0 +1,14 @@
+# Be sure to restart your server when you modify this file.
+
+# Version of your assets, change this if you want to expire all your assets.
+Rails.application.config.assets.version = '1.0'
+
+# Add additional assets to the asset load path.
+# Rails.application.config.assets.paths << Emoji.images_path
+# Add Yarn node_modules folder to the asset load path.
+Rails.application.config.assets.paths << Rails.root.join('node_modules')
+
+# Precompile additional assets.
+# application.js, application.css, and all non-JS/CSS in the app/assets
+# folder are already added.
+# Rails.application.config.assets.precompile += %w( admin.js admin.css )
--- a/example/config/initializers/backtrace_silencers.rb
+++ b/example/config/initializers/backtrace_silencers.rb
@ -0,0 +1,7 @@
+# Be sure to restart your server when you modify this file.
+
+# You can add backtrace silencers for libraries that you're using but don't wish to see in your backtraces.
+# Rails.backtrace_cleaner.add_silencer { |line| line =~ /my_noisy_library/ }
+
+# You can also remove all the silencers if you're trying to debug a problem that might stem from framework code.
+# Rails.backtrace_cleaner.remove_silencers!
--- a/example/config/initializers/content_security_policy.rb
+++ b/example/config/initializers/content_security_policy.rb
@ -0,0 +1,25 @@
+# Be sure to restart your server when you modify this file.
+
+# Define an application-wide content security policy
+# For further information see the following documentation
+# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy
+
+# Rails.application.config.content_security_policy do |policy|
+#   policy.default_src :self, :https
+#   policy.font_src    :self, :https, :data
+#   policy.img_src     :self, :https, :data
+#   policy.object_src  :none
+#   policy.script_src  :self, :https
+#   policy.style_src   :self, :https
+
+#   # Specify URI for violation reports
+#   # policy.report_uri "/csp-violation-report-endpoint"
+# end
+
+# If you are using UJS then enable automatic nonce generation
+# Rails.application.config.content_security_policy_nonce_generator = -> request { SecureRandom.base64(16) }
+
+# Report CSP violations to a specified URI
+# For further information see the following documentation:
+# https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy-Report-Only
+# Rails.application.config.content_security_policy_report_only = true
--- a/example/config/initializers/cookies_serializer.rb
+++ b/example/config/initializers/cookies_serializer.rb
@ -0,0 +1,5 @@
+# Be sure to restart your server when you modify this file.
+
+# Specify a serializer for the signed and encrypted cookie jars.
+# Valid options are :json, :marshal, and :hybrid.
+Rails.application.config.action_dispatch.cookies_serializer = :json
--- a/example/config/initializers/devise.rb
+++ b/example/config/initializers/devise.rb
@ -0,0 +1,299 @@
+# frozen_string_literal: true
+
+# Use this hook to configure devise mailer, warden hooks and so forth.
+# Many of these configuration options can be set straight in your model.
+Devise.setup do |config|
+  # The secret key used by Devise. Devise uses this key to generate
+  # random tokens. Changing this key will render invalid all existing
+  # confirmation, reset password and unlock tokens in the database.
+  # Devise will use the `secret_key_base` as its `secret_key`
+  # by default. You can change it below and use your own secret key.
+  # config.secret_key = 'da45f01cc03f113df2ac8788aab0833ff0ce6d3f2e298e964e0b35c7f63877588054a503106f0102d412987a45ed49e9a49697a6cf66da22f04ca6dafd24f76d'
+
+  # ==> Controller configuration
+  # Configure the parent class to the devise controllers.
+  # config.parent_controller = 'DeviseController'
+
+  # ==> Mailer Configuration
+  # Configure the e-mail address which will be shown in Devise::Mailer,
+  # note that it will be overwritten if you use your own mailer class
+  # with default "from" parameter.
+  config.mailer_sender = 'please-change-me-at-config-initializers-devise@example.com'
+
+  # Configure the class responsible to send e-mails.
+  # config.mailer = 'Devise::Mailer'
+
+  # Configure the parent class responsible to send e-mails.
+  # config.parent_mailer = 'ActionMailer::Base'
+
+  # ==> ORM configuration
+  # Load and configure the ORM. Supports :active_record (default) and
+  # :mongoid (bson_ext recommended) by default. Other ORMs may be
+  # available as additional gems.
+  require 'devise/orm/active_record'
+
+  # ==> Configuration for any authentication mechanism
+  # Configure which keys are used when authenticating a user. The default is
+  # just :email. You can configure it to use [:username, :subdomain], so for
+  # authenticating a user, both parameters are required. Remember that those
+  # parameters are used only when authenticating and not when retrieving from
+  # session. If you need permissions, you should implement that in a before filter.
+  # You can also supply a hash where the value is a boolean determining whether
+  # or not authentication should be aborted when the value is not present.
+  # config.authentication_keys = [:email]
+
+  # Configure parameters from the request object used for authentication. Each entry
+  # given should be a request method and it will automatically be passed to the
+  # find_for_authentication method and considered in your model lookup. For instance,
+  # if you set :request_keys to [:subdomain], :subdomain will be used on authentication.
+  # The same considerations mentioned for authentication_keys also apply to request_keys.
+  # config.request_keys = []
+
+  # Configure which authentication keys should be case-insensitive.
+  # These keys will be downcased upon creating or modifying a user and when used
+  # to authenticate or find a user. Default is :email.
+  config.case_insensitive_keys = [:email]
+
+  # Configure which authentication keys should have whitespace stripped.
+  # These keys will have whitespace before and after removed upon creating or
+  # modifying a user and when used to authenticate or find a user. Default is :email.
+  config.strip_whitespace_keys = [:email]
+
+  # Tell if authentication through request.params is enabled. True by default.
+  # It can be set to an array that will enable params authentication only for the
+  # given strategies, for example, `config.params_authenticatable = [:database]` will
+  # enable it only for database (email + password) authentication.
+  # config.params_authenticatable = true
+
+  # Tell if authentication through HTTP Auth is enabled. False by default.
+  # It can be set to an array that will enable http authentication only for the
+  # given strategies, for example, `config.http_authenticatable = [:database]` will
+  # enable it only for database authentication. The supported strategies are:
+  # :database      = Support basic authentication with authentication key + password
+  # config.http_authenticatable = false
+
+  # If 401 status code should be returned for AJAX requests. True by default.
+  # config.http_authenticatable_on_xhr = true
+
+  # The realm used in Http Basic Authentication. 'Application' by default.
+  # config.http_authentication_realm = 'Application'
+
+  # It will change confirmation, password recovery and other workflows
+  # to behave the same regardless if the e-mail provided was right or wrong.
+  # Does not affect registerable.
+  # config.paranoid = true
+
+  # By default Devise will store the user in session. You can skip storage for
+  # particular strategies by setting this option.
+  # Notice that if you are skipping storage for all authentication paths, you
+  # may want to disable generating routes to Devise's sessions controller by
+  # passing skip: :sessions to `devise_for` in your config/routes.rb
+  config.skip_session_storage = [:http_auth]
+
+  # By default, Devise cleans up the CSRF token on authentication to
+  # avoid CSRF token fixation attacks. This means that, when using AJAX
+  # requests for sign in and sign up, you need to get a new CSRF token
+  # from the server. You can disable this option at your own risk.
+  # config.clean_up_csrf_token_on_authentication = true
+
+  # When false, Devise will not attempt to reload routes on eager load.
+  # This can reduce the time taken to boot the app but if your application
+  # requires the Devise mappings to be loaded during boot time the application
+  # won't boot properly.
+  # config.reload_routes = true
+
+  # ==> Configuration for :database_authenticatable
+  # For bcrypt, this is the cost for hashing the password and defaults to 11. If
+  # using other algorithms, it sets how many times you want the password to be hashed.
+  #
+  # Limiting the stretches to just one in testing will increase the performance of
+  # your test suite dramatically. However, it is STRONGLY RECOMMENDED to not use
+  # a value less than 10 in other environments. Note that, for bcrypt (the default
+  # algorithm), the cost increases exponentially with the number of stretches (e.g.
+  # a value of 20 is already extremely slow: approx. 60 seconds for 1 calculation).
+  config.stretches = Rails.env.test? ? 1 : 11
+
+  # Set up a pepper to generate the hashed password.
+  # config.pepper = 'ea393184081ca269f1d9f2ea8216812c1c487e92eda4f78f35b06cc438c8bee6490ffd1fec0a553505f62ac3305cbc2ccb4973a3e344869bb619f1383624be94'
+
+  # Send a notification to the original email when the user's email is changed.
+  # config.send_email_changed_notification = false
+
+  # Send a notification email when the user's password is changed.
+  # config.send_password_change_notification = false
+
+  # ==> Configuration for :confirmable
+  # A period that the user is allowed to access the website even without
+  # confirming their account. For instance, if set to 2.days, the user will be
+  # able to access the website for two days without confirming their account,
+  # access will be blocked just in the third day.
+  # You can also set it to nil, which will allow the user to access the website
+  # without confirming their account.
+  # Default is 0.days, meaning the user cannot access the website without
+  # confirming their account.
+  # config.allow_unconfirmed_access_for = 2.days
+
+  # A period that the user is allowed to confirm their account before their
+  # token becomes invalid. For example, if set to 3.days, the user can confirm
+  # their account within 3 days after the mail was sent, but on the fourth day
+  # their account can't be confirmed with the token any more.
+  # Default is nil, meaning there is no restriction on how long a user can take
+  # before confirming their account.
+  # config.confirm_within = 3.days
+
+  # If true, requires any email changes to be confirmed (exactly the same way as
+  # initial account confirmation) to be applied. Requires additional unconfirmed_email
+  # db field (see migrations). Until confirmed, new email is stored in
+  # unconfirmed_email column, and copied to email column on successful confirmation.
+  config.reconfirmable = true
+
+  # Defines which key will be used when confirming an account
+  # config.confirmation_keys = [:email]
+
+  # ==> Configuration for :rememberable
+  # The time the user will be remembered without asking for credentials again.
+  # config.remember_for = 2.weeks
+
+  # Invalidates all the remember me tokens when the user signs out.
+  config.expire_all_remember_me_on_sign_out = true
+
+  # If true, extends the user's remember period when remembered via cookie.
+  # config.extend_remember_period = false
+
+  # Options to be passed to the created cookie. For instance, you can set
+  # secure: true in order to force SSL only cookies.
+  # config.rememberable_options = {}
+
+  # ==> Configuration for :validatable
+  # Range for password length.
+  config.password_length = 6..128
+
+  # Email regex used to validate email formats. It simply asserts that
+  # one (and only one) @ exists in the given string. This is mainly
+  # to give user feedback and not to assert the e-mail validity.
+  config.email_regexp = /\A[^@\s]+@[^@\s]+\z/
+
+  # ==> Configuration for :timeoutable
+  # The time you want to timeout the user session without activity. After this
+  # time the user will be asked for credentials again. Default is 30 minutes.
+  # config.timeout_in = 30.minutes
+
+  # ==> Configuration for :lockable
+  # Defines which strategy will be used to lock an account.
+  # :failed_attempts = Locks an account after a number of failed attempts to sign in.
+  # :none            = No lock strategy. You should handle locking by yourself.
+  # config.lock_strategy = :failed_attempts
+
+  # Defines which key will be used when locking and unlocking an account
+  # config.unlock_keys = [:email]
+
+  # Defines which strategy will be used to unlock an account.
+  # :email = Sends an unlock link to the user email
+  # :time  = Re-enables login after a certain amount of time (see :unlock_in below)
+  # :both  = Enables both strategies
+  # :none  = No unlock strategy. You should handle unlocking by yourself.
+  # config.unlock_strategy = :both
+
+  # Number of authentication tries before locking an account if lock_strategy
+  # is failed attempts.
+  # config.maximum_attempts = 20
+
+  # Time interval to unlock the account if :time is enabled as unlock_strategy.
+  # config.unlock_in = 1.hour
+
+  # Warn on the last attempt before the account is locked.
+  # config.last_attempt_warning = true
+
+  # ==> Configuration for :recoverable
+  #
+  # Defines which key will be used when recovering the password for an account
+  # config.reset_password_keys = [:email]
+
+  # Time interval you can reset your password with a reset password key.
+  # Don't put a too small interval or your users won't have the time to
+  # change their passwords.
+  config.reset_password_within = 6.hours
+
+  # When set to false, does not sign a user in automatically after their password is
+  # reset. Defaults to true, so a user is signed in automatically after a reset.
+  # config.sign_in_after_reset_password = true
+
+  # ==> Configuration for :encryptable
+  # Allow you to use another hashing or encryption algorithm besides bcrypt (default).
+  # You can use :sha1, :sha512 or algorithms from others authentication tools as
+  # :clearance_sha1, :authlogic_sha512 (then you should set stretches above to 20
+  # for default behavior) and :restful_authentication_sha1 (then you should set
+  # stretches to 10, and copy REST_AUTH_SITE_KEY to pepper).
+  #
+  # Require the `devise-encryptable` gem when using anything other than bcrypt
+  # config.encryptor = :sha512
+
+  # ==> Scopes configuration
+  # Turn scoped views on. Before rendering "sessions/new", it will first check for
+  # "users/sessions/new". It's turned off by default because it's slower if you
+  # are using only default views.
+  # config.scoped_views = false
+
+  # Configure the default scope given to Warden. By default it's the first
+  # devise role declared in your routes (usually :user).
+  # config.default_scope = :user
+
+  # Set this configuration to false if you want /users/sign_out to sign out
+  # only the current scope. By default, Devise signs out all scopes.
+  # config.sign_out_all_scopes = true
+
+  # ==> Navigation configuration
+  # Lists the formats that should be treated as navigational. Formats like
+  # :html, should redirect to the sign in page when the user does not have
+  # access, but formats like :xml or :json, should return 401.
+  #
+  # If you have any extra navigational formats, like :iphone or :mobile, you
+  # should add them to the navigational formats lists.
+  #
+  # The "*/*" below is required to match Internet Explorer requests.
+  # config.navigational_formats = ['*/*', :html]
+
+  # The default HTTP method used to sign out a resource. Default is :delete.
+  config.sign_out_via = :delete
+
+  # ==> OmniAuth
+  # Add a new OmniAuth provider. Check the wiki for more information on setting
+  # up on your models and hooks.
+  # config.omniauth :github, 'APP_ID', 'APP_SECRET', scope: 'user,public_repo'
+
+  # ==> Warden configuration
+  # If you want to use other strategies, that are not supported by Devise, or
+  # change the failure app, you can configure them inside the config.warden block.
+  #
+  # config.warden do |manager|
+  #   manager.intercept_401 = false
+  #   manager.default_strategies(scope: :user).unshift :some_external_strategy
+  # end
+
+  # ==> Mountable engine configurations
+  # When using Devise inside an engine, let's call it `MyEngine`, and this engine
+  # is mountable, there are some extra configurations to be taken into account.
+  # The following options are available, assuming the engine is mounted as:
+  #
+  #     mount MyEngine, at: '/my_engine'
+  #
+  # The router that invoked `devise_for`, in the example above, would be:
+  # config.router_name = :my_engine
+  #
+  # When using OmniAuth, Devise cannot automatically set OmniAuth path,
+  # so you need to do it manually. For the users scope, it would be:
+  # config.omniauth_path_prefix = '/my_engine/users/auth'
+
+  # ==> Turbolinks configuration
+  # If your app is using Turbolinks, Turbolinks::Controller needs to be included to make redirection work correctly:
+  #
+  # ActiveSupport.on_load(:devise_failure_app) do
+  #   include Turbolinks::Controller
+  # end
+
+  # ==> Configuration for :registerable
+
+  # When set to false, does not sign a user in automatically after their password is
+  # changed. Defaults to true, so a user is signed in automatically after changing a password.
+  # config.sign_in_after_change_password = true
+end
--- a/example/config/initializers/filter_parameter_logging.rb
+++ b/example/config/initializers/filter_parameter_logging.rb
@ -0,0 +1,4 @@
+# Be sure to restart your server when you modify this file.
+
+# Configure sensitive parameters which will be filtered from the log file.
+Rails.application.config.filter_parameters += [:password]
--- a/example/config/initializers/inflections.rb
+++ b/example/config/initializers/inflections.rb
@ -0,0 +1,16 @@
+# Be sure to restart your server when you modify this file.
+
+# Add new inflection rules using the following format. Inflections
+# are locale specific, and you may define rules for as many different
+# locales as you wish. All of these examples are active by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.plural /^(ox)$/i, '\1en'
+#   inflect.singular /^(ox)en/i, '\1'
+#   inflect.irregular 'person', 'people'
+#   inflect.uncountable %w( fish sheep )
+# end
+
+# These inflection rules are supported but not enabled by default:
+# ActiveSupport::Inflector.inflections(:en) do |inflect|
+#   inflect.acronym 'RESTful'
+# end
--- a/example/config/initializers/mime_types.rb
+++ b/example/config/initializers/mime_types.rb
@ -0,0 +1,4 @@
+# Be sure to restart your server when you modify this file.
+
+# Add new mime types for use in respond_to blocks:
+# Mime::Type.register "text/richtext", :rtf
--- a/example/config/initializers/wrap_parameters.rb
+++ b/example/config/initializers/wrap_parameters.rb
@ -0,0 +1,14 @@
+# Be sure to restart your server when you modify this file.
+
+# This file contains settings for ActionController::ParamsWrapper which
+# is enabled by default.
+
+# Enable parameter wrapping for JSON. You can disable this by setting :format to an empty array.
+ActiveSupport.on_load(:action_controller) do
+  wrap_parameters format: [:json]
+end
+
+# To enable root element in JSON for ActiveRecord objects.
+# ActiveSupport.on_load(:active_record) do
+#   self.include_root_in_json = true
+# end
--- a/example/config/locales/devise.en.yml
+++ b/example/config/locales/devise.en.yml
@ -0,0 +1,65 @@
+# Additional translations at https://github.com/plataformatec/devise/wiki/I18n
+
+en:
+  devise:
+    confirmations:
+      confirmed: "Your email address has been successfully confirmed."
+      send_instructions: "You will receive an email with instructions for how to confirm your email address in a few minutes."
+      send_paranoid_instructions: "If your email address exists in our database, you will receive an email with instructions for how to confirm your email address in a few minutes."
+    failure:
+      already_authenticated: "You are already signed in."
+      inactive: "Your account is not activated yet."
+      invalid: "Invalid %{authentication_keys} or password."
+      locked: "Your account is locked."
+      last_attempt: "You have one more attempt before your account is locked."
+      not_found_in_database: "Invalid %{authentication_keys} or password."
+      timeout: "Your session expired. Please sign in again to continue."
+      unauthenticated: "You need to sign in or sign up before continuing."
+      unconfirmed: "You have to confirm your email address before continuing."
+    mailer:
+      confirmation_instructions:
+        subject: "Confirmation instructions"
+      reset_password_instructions:
+        subject: "Reset password instructions"
+      unlock_instructions:
+        subject: "Unlock instructions"
+      email_changed:
+        subject: "Email Changed"
+      password_change:
+        subject: "Password Changed"
+    omniauth_callbacks:
+      failure: "Could not authenticate you from %{kind} because \"%{reason}\"."
+      success: "Successfully authenticated from %{kind} account."
+    passwords:
+      no_token: "You can't access this page without coming from a password reset email. If you do come from a password reset email, please make sure you used the full URL provided."
+      send_instructions: "You will receive an email with instructions on how to reset your password in a few minutes."
+      send_paranoid_instructions: "If your email address exists in our database, you will receive a password recovery link at your email address in a few minutes."
+      updated: "Your password has been changed successfully. You are now signed in."
+      updated_not_active: "Your password has been changed successfully."
+    registrations:
+      destroyed: "Bye! Your account has been successfully cancelled. We hope to see you again soon."
+      signed_up: "Welcome! You have signed up successfully."
+      signed_up_but_inactive: "You have signed up successfully. However, we could not sign you in because your account is not yet activated."
+      signed_up_but_locked: "You have signed up successfully. However, we could not sign you in because your account is locked."
+      signed_up_but_unconfirmed: "A message with a confirmation link has been sent to your email address. Please follow the link to activate your account."
+      update_needs_confirmation: "You updated your account successfully, but we need to verify your new email address. Please check your email and follow the confirm link to confirm your new email address."
+      updated: "Your account has been updated successfully."
+      updated_but_not_signed_in: "Your account has been updated successfully, but since your password was changed, you need to sign in again"
+    sessions:
+      signed_in: "Signed in successfully."
+      signed_out: "Signed out successfully."
+      already_signed_out: "Signed out successfully."
+    unlocks:
+      send_instructions: "You will receive an email with instructions for how to unlock your account in a few minutes."
+      send_paranoid_instructions: "If your account exists, you will receive an email with instructions for how to unlock it in a few minutes."
+      unlocked: "Your account has been unlocked successfully. Please sign in to continue."
+  errors:
+    messages:
+      already_confirmed: "was already confirmed, please try signing in"
+      confirmation_period_expired: "needs to be confirmed within %{period}, please request a new one"
+      expired: "has expired, please request a new one"
+      not_found: "not found"
+      not_locked: "was not locked"
+      not_saved:
+        one: "1 error prohibited this %{resource} from being saved:"
+        other: "%{count} errors prohibited this %{resource} from being saved:"
--- a/example/config/locales/en.yml
+++ b/example/config/locales/en.yml
@ -0,0 +1,33 @@
+# Files in the config/locales directory are used for internationalization
+# and are automatically loaded by Rails. If you want to use locales other
+# than English, add the necessary files in this directory.
+#
+# To use the locales, use `I18n.t`:
+#
+#     I18n.t 'hello'
+#
+# In views, this is aliased to just `t`:
+#
+#     <%= t('hello') %>
+#
+# To use a different locale, set it with `I18n.locale`:
+#
+#     I18n.locale = :es
+#
+# This would use the information in config/locales/es.yml.
+#
+# The following keys must be escaped otherwise they will not be retrieved by
+# the default I18n backend:
+#
+# true, false, on, off, yes, no
+#
+# Instead, surround them with single quotes.
+#
+# en:
+#   'true': 'foo'
+#
+# To learn more, please read the Rails Internationalization guide
+# available at http://guides.rubyonrails.org/i18n.html.
+
+en:
+  hello: "Hello world"
--- a/example/config/puma.rb
+++ b/example/config/puma.rb
@ -0,0 +1,34 @@
+# 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.
+#
+threads_count = ENV.fetch("RAILS_MAX_THREADS") { 5 }
+threads threads_count, threads_count
+
+# Specifies the `port` that Puma will listen on to receive requests; default is 3000.
+#
+port        ENV.fetch("PORT") { 3000 }
+
+# Specifies the `environment` that Puma will run in.
+#
+environment ENV.fetch("RAILS_ENV") { "development" }
+
+# Specifies the number of `workers` to boot in clustered mode.
+# Workers are forked webserver processes. If using threads and workers together
+# the concurrency of the application would be max `threads` * `workers`.
+# Workers do not work on JRuby or Windows (both of which do not support
+# processes).
+#
+# workers ENV.fetch("WEB_CONCURRENCY") { 2 }
+
+# Use the `preload_app!` method when specifying a `workers` number.
+# This directive tells Puma to first boot the application and load code
+# before forking the application. This takes advantage of Copy On Write
+# process behavior so workers use less memory.
+#
+# preload_app!
+
+# Allow puma to be restarted by `rails restart` command.
+plugin :tmp_restart
--- a/example/config/routes.rb
+++ b/example/config/routes.rb
@ -0,0 +1,8 @@
+Rails.application.routes.draw do
+  devise_for :customers
+  devise_for :users
+  resources :products
+  # For details on the DSL available within this file, see http://guides.rubyonrails.org/routing.html
+
+  root to: "home#index"
+end
--- a/example/config/spring.rb
+++ b/example/config/spring.rb
@ -0,0 +1,6 @@
+%w[
+  .ruby-version
+  .rbenv-vars
+  tmp/restart.txt
+  tmp/caching-dev.txt
+].each { |path| Spring.watch(path) }
--- a/example/config/storage.yml
+++ b/example/config/storage.yml
@ -0,0 +1,34 @@
+test:
+  service: Disk
+  root: <%= Rails.root.join("tmp/storage") %>
+
+local:
+  service: Disk
+  root: <%= Rails.root.join("storage") %>
+
+# Use rails credentials:edit to set the AWS secrets (as aws:access_key_id|secret_access_key)
+# amazon:
+#   service: S3
+#   access_key_id: <%= Rails.application.credentials.dig(:aws, :access_key_id) %>
+#   secret_access_key: <%= Rails.application.credentials.dig(:aws, :secret_access_key) %>
+#   region: us-east-1
+#   bucket: your_own_bucket
+
+# Remember not to checkin your GCS keyfile to a repository
+# google:
+#   service: GCS
+#   project: your_project
+#   credentials: <%= Rails.root.join("path/to/gcs.keyfile") %>
+#   bucket: your_own_bucket
+
+# Use rails credentials:edit to set the Azure Storage secret (as azure_storage:storage_access_key)
+# microsoft:
+#   service: AzureStorage
+#   storage_account_name: your_account_name
+#   storage_access_key: <%= Rails.application.credentials.dig(:azure_storage, :storage_access_key) %>
+#   container: your_container_name
+
+# mirror:
+#   service: Mirror
+#   primary: local
+#   mirrors: [ amazon, google, microsoft ]
--- a/example/db/migrate/20190322181705_devise_create_users.rb
+++ b/example/db/migrate/20190322181705_devise_create_users.rb
@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+class DeviseCreateUsers < ActiveRecord::Migration[5.2]
+  def change
+    create_table :users do |t|
+      t.string :full_name, null: false
+      t.string :phone
+      t.string :avatar
+
+      ## Database authenticatable
+      t.string :email,              null: false, default: ""
+      t.string :encrypted_password, null: false, default: ""
+
+      ## Recoverable
+      t.string   :reset_password_token
+      t.datetime :reset_password_sent_at
+
+      ## Rememberable
+      t.datetime :remember_created_at
+
+      ## Trackable
+      # t.integer  :sign_in_count, default: 0, null: false
+      # t.datetime :current_sign_in_at
+      # t.datetime :last_sign_in_at
+      # t.inet     :current_sign_in_ip
+      # t.inet     :last_sign_in_ip
+
+      ## Confirmable
+      # t.string   :confirmation_token
+      # t.datetime :confirmed_at
+      # t.datetime :confirmation_sent_at
+      # t.string   :unconfirmed_email # Only if using reconfirmable
+
+      ## Lockable
+      # t.integer  :failed_attempts, default: 0, null: false # Only if lock strategy is :failed_attempts
+      # t.string   :unlock_token # Only if unlock strategy is :email or :both
+      # t.datetime :locked_at
+
+
+      t.timestamps null: false
+    end
+
+    add_index :users, :email,                unique: true
+    add_index :users, :reset_password_token, unique: true
+    # add_index :users, :confirmation_token,   unique: true
+    # add_index :users, :unlock_token,         unique: true
+  end
+end
--- a/example/db/migrate/20190322181706_devise_create_customers.rb
+++ b/example/db/migrate/20190322181706_devise_create_customers.rb
@ -0,0 +1,47 @@
+# frozen_string_literal: true
+
+class DeviseCreateCustomers < ActiveRecord::Migration[5.2]
+  def change
+    create_table :customers do |t|
+      t.string :full_name, null: false
+      t.string :phone
+
+      ## Database authenticatable
+      t.string :email,              null: false, default: ""
+      t.string :encrypted_password, null: false, default: ""
+
+      ## Recoverable
+      t.string   :reset_password_token
+      t.datetime :reset_password_sent_at
+
+      ## Rememberable
+      t.datetime :remember_created_at
+
+      ## Trackable
+      # t.integer  :sign_in_count, default: 0, null: false
+      # t.datetime :current_sign_in_at
+      # t.datetime :last_sign_in_at
+      # t.inet     :current_sign_in_ip
+      # t.inet     :last_sign_in_ip
+
+      ## Confirmable
+      # t.string   :confirmation_token
+      # t.datetime :confirmed_at
+      # t.datetime :confirmation_sent_at
+      # t.string   :unconfirmed_email # Only if using reconfirmable
+
+      ## Lockable
+      # t.integer  :failed_attempts, default: 0, null: false # Only if lock strategy is :failed_attempts
+      # t.string   :unlock_token # Only if unlock strategy is :email or :both
+      # t.datetime :locked_at
+
+
+      t.timestamps null: false
+    end
+
+    add_index :customers, :email,                unique: true
+    add_index :customers, :reset_password_token, unique: true
+    # add_index :customers, :confirmation_token,   unique: true
+    # add_index :customers, :unlock_token,         unique: true
+  end
+end
--- a/example/db/migrate/20190322181710_create_products.rb
+++ b/example/db/migrate/20190322181710_create_products.rb
@ -0,0 +1,12 @@
+class CreateProducts < ActiveRecord::Migration[5.2]
+  def change
+    create_table :products do |t|
+      t.string :name
+      t.text :description
+      t.decimal :price, precision: 7, scale: 2
+      t.belongs_to :user, foreign_key: true
+
+      t.timestamps
+    end
+  end
+end
--- a/example/db/migrate/20190322200743_purchases.rb
+++ b/example/db/migrate/20190322200743_purchases.rb
@ -0,0 +1,12 @@
+class Purchases < ActiveRecord::Migration[5.2]
+  def change
+    create_table :purchases do |t|
+      t.references :customer, foreign_key: true
+      t.references :product, foreign_key: true
+      t.string :sale_type
+      t.integer :quantity
+      t.datetime :due_date
+      t.datetime :returned
+    end
+  end
+end
--- a/example/db/schema.rb
+++ b/example/db/schema.rb
@ -0,0 +1,71 @@
+# This file is auto-generated from the current state of the database. Instead
+# of editing this file, please use the migrations feature of Active Record to
+# incrementally modify your database, and then regenerate this schema definition.
+#
+# Note that this schema.rb definition is the authoritative source for your
+# database schema. If you need to create the application database on another
+# system, you should be using db:schema:load, not running all the migrations
+# from scratch. The latter is a flawed and unsustainable approach (the more migrations
+# you'll amass, the slower it'll run and the greater likelihood for issues).
+#
+# It's strongly recommended that you check this file into your version control system.
+
+ActiveRecord::Schema.define(version: 2019_03_22_200743) do
+
+  # These are extensions that must be enabled in order to support this database
+  enable_extension "plpgsql"
+
+  create_table "customers", force: :cascade do |t|
+    t.string "full_name", null: false
+    t.string "phone"
+    t.string "email", default: "", null: false
+    t.string "encrypted_password", default: "", null: false
+    t.string "reset_password_token"
+    t.datetime "reset_password_sent_at"
+    t.datetime "remember_created_at"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["email"], name: "index_customers_on_email", unique: true
+    t.index ["reset_password_token"], name: "index_customers_on_reset_password_token", unique: true
+  end
+
+  create_table "products", force: :cascade do |t|
+    t.string "name"
+    t.text "description"
+    t.decimal "price", precision: 7, scale: 2
+    t.bigint "user_id"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["user_id"], name: "index_products_on_user_id"
+  end
+
+  create_table "purchases", force: :cascade do |t|
+    t.bigint "customer_id"
+    t.bigint "product_id"
+    t.string "sale_type"
+    t.integer "quantity"
+    t.datetime "due_date"
+    t.datetime "returned"
+    t.index ["customer_id"], name: "index_purchases_on_customer_id"
+    t.index ["product_id"], name: "index_purchases_on_product_id"
+  end
+
+  create_table "users", force: :cascade do |t|
+    t.string "full_name", null: false
+    t.string "phone"
+    t.string "avatar"
+    t.string "email", default: "", null: false
+    t.string "encrypted_password", default: "", null: false
+    t.string "reset_password_token"
+    t.datetime "reset_password_sent_at"
+    t.datetime "remember_created_at"
+    t.datetime "created_at", null: false
+    t.datetime "updated_at", null: false
+    t.index ["email"], name: "index_users_on_email", unique: true
+    t.index ["reset_password_token"], name: "index_users_on_reset_password_token", unique: true
+  end
+
+  add_foreign_key "products", "users"
+  add_foreign_key "purchases", "customers"
+  add_foreign_key "purchases", "products"
+end
--- a/example/db/seeds.rb
+++ b/example/db/seeds.rb
@ -0,0 +1,82 @@
+# This file should contain all the record creation needed to seed the database with its default values.
+# The data can then be loaded with the rails db:seed command (or created alongside the database with db:setup).
+#
+# Examples:
+#
+#   movies = Movie.create([{ name: 'Star Wars' }, { name: 'Lord of the Rings' }])
+#   Character.create(name: 'Luke', movie: movies.first)
+
+pwd = "123456"
+
+user_count = 10
+customer_count = 100
+product_count = 50
+purchase_count = 100
+
+user_count.times do |i|
+  user = User.create(
+    full_name: Faker::Name.name,
+    avatar: Faker::Avatar.image,
+    phone: Faker::PhoneNumber.cell_phone,
+    email: Faker::Internet.email,
+    password: pwd,
+    password_confirmation: pwd
+  )
+  user.save!
+  puts user.inspect
+end
+
+customer_count.times do |i|
+  customer = Customer.create(
+    full_name: Faker::Name.name,
+    phone: Faker::PhoneNumber.cell_phone,
+    email: Faker::Internet.email,
+    password: pwd,
+    password_confirmation: pwd
+  )
+  customer.save!
+  puts customer.inspect
+end
+
+product_count.times do |i|
+  desc = [
+    Faker::Beer.brand,
+    Faker::Beer.style, 
+    Faker::Beer.hop,
+    Faker::Beer.yeast,
+    Faker::Beer.ibu,
+    Faker::Beer.alcohol,
+    Faker::Beer.blg,
+  ].join(", ")
+
+  product = Product.create(
+    name: Faker::Beer.name,
+    description: desc,
+    price: rand(5.5..19.0),
+    user_id: rand(1..user_count)
+  )
+  product.save!
+  puts product.inspect
+end
+
+purchase_count.times do |i|
+  sale_type = ["rented", "bought"].sample
+
+  if sale_type == "rented"
+    due_date = Faker::Date.forward(30)
+    if [0, 3].sample == 1
+      returned = Faker::Date.forward(60)
+    end
+  end
+
+  purchase = Purchase.create(
+    customer_id: rand(1..customer_count),
+    product_id: rand(1..product_count),
+    sale_type: sale_type,
+    quantity: rand(1..10),
+    due_date: due_date,
+    returned: returned
+  )
+  purchase.save!
+  puts purchase.inspect
+end
--- a/example/entrypoint.sh
+++ b/example/entrypoint.sh
@ -0,0 +1,8 @@
+#!/bin/bash
+set -e
+
+# Remove a potentially pre-existing server.pid for Rails.
+rm -f /myapp/tmp/pids/server.pid
+
+# Then exec the container's main process (what's set as CMD in the Dockerfile).
+exec "$@"
--- a/example/lib/assets/.keep
+++ b/example/lib/assets/.keep
--- a/example/lib/tasks/.keep
+++ b/example/lib/tasks/.keep
--- a/example/log/.keep
+++ b/example/log/.keep
--- a/example/package.json
+++ b/example/package.json
@ -0,0 +1,5 @@
+{
+  "name": "app",
+  "private": true,
+  "dependencies": {}
+}
--- a/example/public/404.html
+++ b/example/public/404.html
@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The page you were looking for doesn't exist (404)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/404.html -->
+  <div class="dialog">
+    <div>
+      <h1>The page you were looking for doesn't exist.</h1>
+      <p>You may have mistyped the address or the page may have moved.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
--- a/example/public/422.html
+++ b/example/public/422.html
@ -0,0 +1,67 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>The change you wanted was rejected (422)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/422.html -->
+  <div class="dialog">
+    <div>
+      <h1>The change you wanted was rejected.</h1>
+      <p>Maybe you tried to change something you didn't have access to.</p>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
--- a/example/public/500.html
+++ b/example/public/500.html
@ -0,0 +1,66 @@
+<!DOCTYPE html>
+<html>
+<head>
+  <title>We're sorry, but something went wrong (500)</title>
+  <meta name="viewport" content="width=device-width,initial-scale=1">
+  <style>
+  .rails-default-error-page {
+    background-color: #EFEFEF;
+    color: #2E2F30;
+    text-align: center;
+    font-family: arial, sans-serif;
+    margin: 0;
+  }
+
+  .rails-default-error-page div.dialog {
+    width: 95%;
+    max-width: 33em;
+    margin: 4em auto 0;
+  }
+
+  .rails-default-error-page div.dialog > div {
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #BBB;
+    border-top: #B00100 solid 4px;
+    border-top-left-radius: 9px;
+    border-top-right-radius: 9px;
+    background-color: white;
+    padding: 7px 12% 0;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+
+  .rails-default-error-page h1 {
+    font-size: 100%;
+    color: #730E15;
+    line-height: 1.5em;
+  }
+
+  .rails-default-error-page div.dialog > p {
+    margin: 0 0 1em;
+    padding: 1em;
+    background-color: #F7F7F7;
+    border: 1px solid #CCC;
+    border-right-color: #999;
+    border-left-color: #999;
+    border-bottom-color: #999;
+    border-bottom-left-radius: 4px;
+    border-bottom-right-radius: 4px;
+    border-top-color: #DADADA;
+    color: #666;
+    box-shadow: 0 3px 8px rgba(50, 50, 50, 0.17);
+  }
+  </style>
+</head>
+
+<body class="rails-default-error-page">
+  <!-- This file lives in public/500.html -->
+  <div class="dialog">
+    <div>
+      <h1>We're sorry, but something went wrong.</h1>
+    </div>
+    <p>If you are the application owner check the logs for more information.</p>
+  </div>
+</body>
+</html>
--- a/example/public/apple-touch-icon-precomposed.png
+++ b/example/public/apple-touch-icon-precomposed.png
--- a/example/public/apple-touch-icon.png
+++ b/example/public/apple-touch-icon.png
--- a/example/public/favicon.ico
+++ b/example/public/favicon.ico
--- a/example/public/robots.txt
+++ b/example/public/robots.txt
@ -0,0 +1 @@
+# See http://www.robotstxt.org/robotstxt.html for documentation on how to use the robots.txt file
--- a/Show More
+++ b/Show More
				`@ -0,0 +1 @@`
				`json.array! @products, partial: 'products/product', as: :product`
				`@ -0,0 +1 @@`
				`json.partial! "products/product", product: @product`
				`@ -0,0 +1 @@`
				`ze/YtOkYCXCK6/Rd4s3aPDyKyUvhbe5FnZR47QG38a2bfQ/9SjQ9eI44fJcTamD3YegF2WfChuWHOfrxQHZqg9d2MKhSzXtBOfNL9Ym1cgLkhGjoxBUoEvKPZHeMW5RMHOnpzyVexvt3Yho5XSdNta7ic6oQBGRSPNUF5OB1G2Kcu6PtIBD7d7X2GQcjzVpsh8IXEK63HQ7lsywK3RSy2DqkkioH3ZOHZgd4xUKCofhiMxe7sxqo9nid+zKiqGnjnnKQ4ferXqCyF/wIRwTbD5kZ/w0yohsq8afVZJEQ9x5ZmPB09x/S5j3Wv87MpBFpHYWh/W7A0Ede+zJE9dyJRlRFaipclA1c0R2wrL0xeTcoA3U1pyRDKxaIU/0AYaxJ3ShNRy3rsDFtqvSlfGuHh4zGYDBk2dZ+NeLU--7folMaIoT99K7IAL--5XdEoGfrgiSYInpqOpRR+w==`
				`@ -0,0 +1 @@`
				`# See http://www.robotstxt.org/robotstxt.html for documentation on how to use the robots.txt file`