paircolumbus · gwadej · Oct 12, 2015 · Oct 12, 2015 · Oct 13, 2015 · Oct 13, 2015
diff --git a/source/Gemfile b/source/Gemfile
@@ -26,8 +26,11 @@ gem 'sdoc', '~> 0.4.0',          group: :doc
 # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
 gem 'spring',        group: :development
 
+# Bootstrap
+gem 'bootstrap-sass',       '3.2.0'
+
 # Use ActiveModel has_secure_password
-# gem 'bcrypt', '~> 3.1.7'
+gem 'bcrypt', '~> 3.1.7'
 
 # Use unicorn as the app server
 # gem 'unicorn'
@@ -37,5 +40,6 @@ gem 'spring',        group: :development
 
 # Use debugger
 # gem 'debugger', group: [:development, :test]
- gem 'rspec-rails', group: [:development, :test]
+gem 'rspec-rails', group: [:development, :test]
 
+gem 'autoprefixer-rails'
diff --git a/source/app/assets/stylesheets/urls.css.scss b/source/app/assets/stylesheets/urls.css.scss
@@ -1,3 +1,6 @@
 // Place all the styles related to the Urls controller here.
 // They will automatically be included in application.css.
 // You can use Sass (SCSS) here: http://sass-lang.com/
+.error {
+    color: red;
+}
diff --git a/source/app/controllers/urls_controller.rb b/source/app/controllers/urls_controller.rb
@@ -1,2 +1,44 @@
 class UrlsController < ApplicationController
+  def index
+    # for now, lets grab them all and pass them to a display page
+    @urls = Url.all
+  end
+
+  def new
+    # default behavior looks good
+    @target = ''
+    @save_errors = nil
+  end
+
+  def _extract_url_errors(url)
+    index = [:target_link, :linkid, :base].find { |i| url.errors[i].any? }
+    return nil if index.nil?
+    url.errors[index]
+  end
+
+  def create
+    # Actually create the new shortened url
+    @target = params[:target_link]
+    @errors = nil
+
+    @url = Url.new(target_link: @target)
+    if @url.save
+      redirect_to @url
+    else
+      @errors = _extract_url_errors(@url) ||
+                ['Unable to save URL. Please try another.']
+      render 'new'
+    end
+  end
+
+  def show
+    @url = Url.find(params[:id])
+  end
+
+  # redirect to the long url
+  def follow
+    url = Url.find_by(linkid: params[:linkid])
+    Url.increment_counter(:click_count, url.id)
+    redirect_to url.target_link
+  end
 end
diff --git a/source/app/helpers/urls_helper.rb b/source/app/helpers/urls_helper.rb
@@ -1,2 +1,8 @@
 module UrlsHelper
+  module_function
+  LINKID_LENGTH = 8
+
+  def shortened_linkid(url)
+    Digest::SHA1.base64digest(url)[0, LINKID_LENGTH].tr('+/','-_')
+  end
 end
diff --git a/source/app/models/url.rb b/source/app/models/url.rb
@@ -0,0 +1,43 @@
+require 'uri'
+require 'net/http'
+
+class Url < ActiveRecord::Base
+  before_save :ensure_short_link
+  validates :linkid, uniqueness: true
+  validate :target_link_not_empty, :target_link_must_be_http,
+    :target_link_must_be_reachable
+
+  def target_link_not_empty
+    return unless errors.empty?
+    return unless target_link.blank?
+    errors[:target_link] << 'Target URL cannot be blank'
+  end
+
+  def target_link_must_be_http
+    return unless errors.empty?
+    return if target_link.match(%r{\Ahttps?://})
+    errors[:target_link] << 'Target URL has an unrecognized scheme'
+  end
+
+  def _get_target_response_code
+    uri = URI.parse(target_link)
+    resp = Net::HTTP.get_response(uri)
+    resp.code.to_i
+  end
+
+  def target_link_must_be_reachable
+    return unless errors.empty?
+    return if _get_target_response_code < 400
+    errors[:target_link] << 'Target URL is not found'
+  rescue URI::InvalidURIError
+    errors[:target_link] << 'Target URL is not valid'
+    return
+  rescue
+    errors[:target_link] << 'Target URL is not reachable'
+  end
+
+  def ensure_short_link
+    return unless linkid.nil? || linkid.empty?
+    self.linkid = UrlsHelper.shortened_linkid(target_link)
+  end
+end
diff --git a/source/app/views/layouts/application.html.erb b/source/app/views/layouts/application.html.erb
@@ -1,7 +1,7 @@
 <!DOCTYPE html>
 <html>
 <head>
-  <title>Source</title>
+  <title>URL Shortener</title>
   <%= stylesheet_link_tag    'application', media: 'all', 'data-turbolinks-track' => true %>
   <%= javascript_include_tag 'application', 'data-turbolinks-track' => true %>
   <%= csrf_meta_tags %>

diff --git a/source/app/views/urls/index.html.erb b/source/app/views/urls/index.html.erb
@@ -0,0 +1,16 @@
+<h1>URL Shortcuts</h1>
+
+<a href="<%= new_url_path %>">Get new shortened URL</a>
+<% if [email protected]? && @urls.size != 0 %>
+<table>
+  <thead>
+    <tr><th>Shortened ID</th><th>Target</th></tr>
+  </thead>
+<% @urls.each do |url| %>
+  <tr><td><a href="<%= url_url(url.id) %>"><%= url.linkid %></a></td>
+    <td><a href="<%= url.target_link %>"><%= url.target_link %></a></td></tr>
+<% end %>
+</table>
+<% else %>
+<p>No shortened URLs found</p>
+<% end %>
diff --git a/source/app/views/urls/new.html.erb b/source/app/views/urls/new.html.erb
@@ -0,0 +1,13 @@
+<h1>URL Shortener</h1>
+<% if [email protected]? && @errors.size > 0 %>
+  <%   @errors.each do |err| %>
+  <p class="error"><%= err %></p>
+  <% end %>
+<% end %>
+<form id="new_url" method="post" action="<%= urls_path %>">
+  <input name="authenticity_token" type="hidden" value="<%= form_authenticity_token %>"/>
+  <label for="#target_link">Target:</label>
+  <input type="text" name="target_link" id="target_link" size="100" placeholder="http://example.com/cool_page.html" value="<%= @target || '' %>">
+  <button class="btn btn-primary" type="submit">Shorten</button>
+</form>
+<a href="<%= urls_path %>">Back to list</a>
diff --git a/source/app/views/urls/show.html.erb b/source/app/views/urls/show.html.erb
@@ -0,0 +1,23 @@
+<h1>URL Shortcut</h1>
+
+<a href="<%= urls_path %>">Back to list</a>
+
+<% if @url.nil? %>
+<p>Unrecognized Shortcut.</p>
+<% else %>
+<table>
+  <tr>
+    <th>Shortened Link</th>
+    <td><a href="<%= follow_path(@url.linkid) %>"><%= follow_url(@url.linkid) %></a></td>
+  </tr>
+  <tr>
+    <th>Target Link</th>
+    <td><a href="<%= @url.target_link %>"><%= @url.target_link %></a></td>
+  </tr>
+  <tr>
+    <th>Click Count</th>
+    <td><%= @url.click_count %></td>
+  </tr>
+</table>
+<% end %>
+
diff --git a/source/config/routes.rb b/source/config/routes.rb
@@ -13,6 +13,9 @@
 
   # Example resource route (maps HTTP verbs to controller actions automatically):
   #   resources :products
+  resources :urls, except: [ :edit, :update, :destroy ]
+
+  get '/:linkid', to: 'urls#follow', as: :follow, constraints: { linkid: /[-_a-zA-Z0-9]{8}/ }
 
   # Example resource route with options:
   #   resources :products do

diff --git a/source/db/migrate/20151012124222_create_urls.rb b/source/db/migrate/20151012124222_create_urls.rb
@@ -0,0 +1,11 @@
+class CreateUrls < ActiveRecord::Migration
+  def change
+    create_table :urls do |t|
+      t.string :linkid, limit: 8
+      t.string :target_link, limit: 1024
+
+      t.timestamps
+    end
+    add_index :urls, :linkid, unique: true
+  end
+end
diff --git a/source/db/migrate/20151012132805_add_click_count_to_url.rb b/source/db/migrate/20151012132805_add_click_count_to_url.rb
@@ -0,0 +1,5 @@
+class AddClickCountToUrl < ActiveRecord::Migration
+  def change
+    add_column :urls, :click_count, :integer, :default => 0
+  end
+end
diff --git a/source/db/schema.rb b/source/db/schema.rb
@@ -0,0 +1,26 @@
+# encoding: UTF-8
+# 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: 20151012132805) do
+
+  create_table "urls", force: true do |t|
+    t.string   "linkid",      limit: 8
+    t.string   "target_link", limit: 1024
+    t.datetime "created_at"
+    t.datetime "updated_at"
+    t.integer  "click_count",              default: 0
+  end
+
+  add_index "urls", ["linkid"], name: "index_urls_on_linkid", unique: true
+
+end
diff --git a/source/db/seeds.rb b/source/db/seeds.rb
@@ -5,3 +5,5 @@
 #
 #   cities = City.create([{ name: 'Chicago' }, { name: 'Copenhagen' }])
 #   Mayor.create(name: 'Emanuel', city: cities.first)
+Url.create([{target_link: 'https://google.com'},
+            {target_link: 'http://guides.rubyonrails.org/v4.1.12/action_controller_overview.html'}])
diff --git a/source/spec/controllers/urls_controller_spec.rb b/source/spec/controllers/urls_controller_spec.rb
@@ -0,0 +1,99 @@
+require 'rails_helper'
+
+# This spec was generated by rspec-rails when you ran the scaffold generator.
+# It demonstrates how one might use RSpec to specify the controller code that
+# was generated by Rails when you ran the scaffold generator.
+#
+# It assumes that the implementation code is generated by the rails scaffold
+# generator.  If you are using any extension libraries to generate different
+# controller code, this generated spec may or may not pass.
+#
+# It only uses APIs available in rails and/or rspec-rails.  There are a number
+# of tools you can use to make these specs even more expressive, but we're
+# sticking to rails and rspec-rails APIs to keep things simple and stable.
+#
+# Compared to earlier versions of this generator, there is very limited use of
+# stubs and message expectations in this spec.  Stubs are only used when there
+# is no simpler way to get a handle on the object needed for the example.
+# Message expectations are only used when there is no simpler way to specify
+# that an instance is receiving a specific message.
+
+RSpec.describe UrlsController, type: :controller do
+  # This should return the minimal set of attributes required to create a valid
+  # Url. As you add validations to Url, be sure to
+  # adjust the attributes here as well.
+  let(:valid_attributes) { { target_link: 'http://google.com/' } }
+
+  let(:invalid_attributes) { { target_link: 'wqaesrdtfyjguhj' } }
+
+  # This should return the minimal set of values that should be in the session
+  # in order to pass any filters (e.g. authentication) defined in
+  # UrlsController. Be sure to keep this updated too.
+  let(:valid_session) { {} }
+
+  describe 'GET index' do
+    it 'assigns all urls as @urls' do
+      url = Url.create! valid_attributes
+      get :index, {}, valid_session
+      expect(assigns(:urls)).to eq([url])
+    end
+  end
+
+  describe 'GET show' do
+    it 'assigns the requested url as @url' do
+      url = Url.create! valid_attributes
+      get :show, { id: url.id }, valid_session
+      expect(assigns(:url)).to eq(url)
+    end
+  end
+
+  describe 'GET new' do
+    subject { get :new, {}, valid_session }
+
+    it 'renders the new Url form' do
+      expect(subject.status).to eq 200
+      expect(subject).to render_template :new
+    end
+  end
+
+  describe 'POST create' do
+    describe 'with valid params' do
+      it 'creates a new Url' do
+        expect { post :create, valid_attributes, valid_session }
+          .to change(Url, :count).by(1)
+        expect(response).to redirect_to(Url.last)
+      end
+    end
+
+    describe 'with invalid params' do
+      subject { post :create, invalid_attributes, valid_session }
+      it 're-renders the new template' do
+        expect(subject).to render_template :new
+      end
+    end
+
+    describe 'with missing target' do
+      subject { post :create, { target_link: '' }, valid_session }
+      it 're-renders the new template' do
+        expect(subject).to render_template :new
+      end
+    end
+
+    describe 'with unreachable link' do
+      bad_link = 'http://a.a.a.a.a.a.a/'
+      subject { post :create, { target_link: bad_link }, valid_session }
+      it 're-renders the new template' do
+        expect(subject).to render_template :new
+      end
+    end
+  end
+
+  describe 'GET follow' do
+    let(:url) { Url.create! valid_attributes }
+
+    it 'redirects to target' do
+      get :follow, { linkid: url.linkid }, valid_session
+      expect(response).to redirect_to url.target_link
+    end
+  end
+end
diff --git a/source/spec/helpers/urls_helper_spec.rb b/source/spec/helpers/urls_helper_spec.rb
@@ -0,0 +1,18 @@
+require_relative '../../app/helpers/urls_helper'
+
+describe 'UrlsHelper' do
+  let(:target) { 'http://covermymeds.com/' }
+  let(:linkid) { UrlsHelper.shortened_linkid(target) }
+
+  it 'returns a proper length linkid' do
+    expect(linkid.length).to eq UrlsHelper::LINKID_LENGTH
+  end
+
+  it 'linkid only contains legal characters' do
+    expect(linkid).to match(/^[-_a-zA-Z0-9]{8}$/)
+  end
+
+  it 'linkid length can\'t change with changing schema' do
+    expect(UrlsHelper::LINKID_LENGTH).to eq 8
+  end
+end