Fix css to xpath, and validates model

app/models/area.rb

 class Area < ApplicationRecord
   has_many :city
+
+  validates :name, presence: true
 end

app/models/category.rb

 class Category < ApplicationRecord
   has_many :job_category
+
+  validates :name, presence: true
 end

app/models/city.rb

 class City < ApplicationRecord
   belongs_to :area
-
   has_many :job
+
+  validates :name, presence: true
 end

app/models/company.rb

 class Company < ApplicationRecord
   has_many :job
+
+  validates :name, presence: true
+  validates :address, length: { maximum: 200 }
+  validates :district, length: { maximum: 200 }
+  validates :province, length: { maximum: 200 }
 end

app/models/job.rb

@@ -5,4 +5,6 @@ class Job < ApplicationRecord
   belongs_to :contact, optional: true
 
   has_many :job_category
+
+  validates :name, presence: true, length: { maximum: 200 }
 end

app/models/user.rb

 class User < ApplicationRecord
+  validates :name, presence: true, length: { maximum: 50 }
+  VALID_EMAIL_REGEX = /\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i
+  validates :email, presence: true, length: { maximum: 255 }, format: { with: VALID_EMAIL_REGEX }
 end

db/migrate/20170628014259_create_areas.rb

 class CreateAreas < ActiveRecord::Migration[5.1]
   def change
     create_table :areas do |t|
-      t.string :name
+      t.string :name, index: true
 
       t.timestamps
     end

db/migrate/20170628014343_create_categories.rb

 class CreateCategories < ActiveRecord::Migration[5.1]
   def change
     create_table :categories do |t|
-      t.string :name
+      t.string :name, idnex: true
 
       t.timestamps
     end

db/migrate/20170628014941_create_cities.rb

 class CreateCities < ActiveRecord::Migration[5.1]
   def change
     create_table :cities do |t|
-      t.string :name
+      t.string :name, index: true
       t.references :area, index: true
 
       t.timestamps

db/migrate/20170628015337_create_jobs.rb

 class CreateJobs < ActiveRecord::Migration[5.1]
   def change
     create_table :jobs do |t|
-      t.string :name
+      t.string :name, index: true
       t.text :description
       t.references :city, index: true
       t.string :salary

lib/tasks/crawler_data.rake

@@ -9,8 +9,8 @@ namespace :crawler_data do
     import_category(doc)
     import_city(doc)
 
-    new_jobs_url = doc.css('div.logo_nav li.hasmenu li a')[0]['href']
-    inport_job(new_jobs_url)
+    new_jobs_url = doc.xpath("//div[@class='logo_nav']/ul/li[@class=' hasmenu']/ul/li/a[text()='Việc làm mới nhất']/@href")
+    inport_job(new_jobs_url.to_s)
   end
 
   def import_area
@@ -19,19 +19,19 @@ namespace :crawler_data do
   end
 
   def import_category(doc)
-    categories = doc.css('div.s-home2 div#NewSearchJob3 div.box_multiSelect_industry option')
+    categories = doc.xpath("//div[@class='s-home2']/div[@id='NewSearchJob3']/form/div[@class='search-horizontal']/div[@class='ui-widget box_multiSelect_industry']/select/option")
     categories = categories.slice(1..categories.size - 2)
     categories.each do |category|
-      Category.new(name: category.text).save if Category.where(name: category.text).blank?
+      Category.new(name: category.text.strip).save if Category.where(name: category.text.strip).blank?
     end
   end
 
   def import_city(doc)
-    cities = doc.css('div.s-home2 div#NewSearchJob3 div.box_multiSelect_location option').drop(1)
+    cities = doc.xpath("//div[@class='s-home2']//div[@id='NewSearchJob3']/form/div[@class='search-horizontal']/div[@class='ui-widget box_multiSelect_location']/select/option").drop(1)
     area_id = 1
     cities.each do |city|
       area_id = 2 if city.text == 'Angola'
-      City.new(name: city.text, area: Area.find(area_id)).save if City.where(name: city.text).blank?
+      City.new(name: city.text.strip, area: Area.find(area_id)).save if City.where(name: city.text.strip).blank?
     end
   end
 
@@ -40,46 +40,44 @@ namespace :crawler_data do
       doc_new_jobs = Nokogiri::HTML(open(url))
       doc_new_jobs.encoding = 'utf-8'
 
-      doc_new_jobs.css('div.gird_standard dl dd h3 a').each do |link|
-        encoded_url = URI.encode(link['href'])
+      doc_new_jobs.xpath("//div[@class='gird_standard ']/dl/dd/span/h3[@class='job']/a/@href").each do |link|
+        encoded_url = URI.encode(link.to_s)
         doc_job_details = Nokogiri::HTML(open(encoded_url))
 
         # Company Information
-        company_name = doc_job_details.css('div.tit_company').text # Company name
-        company_address = doc_job_details.css("div.box1Detail label[itemprop='addressLocality']").text # Company Address
-        company_description = doc_job_details.css('div.desc_company').text # Company description
+        company_name = doc_job_details.xpath("//div[@class='tit_company']").text.strip # Company name
+        company_address = doc_job_details.xpath("//div[@class='box1Detail']/p[@class='TitleDetailNew']/label[@itemprop='address']/label[@itemprop='addressLocality']").text.strip # Company Address
+        company_description = doc_job_details.xpath("//div[@class='desc_company content_fck']").text.strip # Company description
         Company.new(name: company_name, address: company_address, description: company_description).save if Company.where(name: company_name).blank?
 
-        # Job Information
-        job_name = doc_job_details.css('div.LeftJobCB h1').text # Job name
-        job_description = doc_job_details.css('div.MarBot20').text # Job description
-        doc_job_details.css('ul.DetailJobNew span').each do |detail|
-          case detail.text.strip
-          when 'Nơi làm việc:'
-            @job_location = detail.parent.css("b[itemprop='jobLocation']").text # Job location
-          when 'Cấp bậc:'
-            @job_level = detail.parent.css("label[itemprop='occupationalCategory']").text # Job level
-          when 'Kinh nghiệm:'
-            @job_experience = detail.parent.children.last.text # Job experience
-          when 'Lương:'
-            @job_salary = detail.parent.css("label[itemprop='baseSalary']").text + detail.parent.css("label[itemprop='salaryCurrency']").text # Job salary
-          when 'Ngành nghề:'
-            @job_category = detail.parent.css("b a[itemprop='industry']").text # Job category
-          when 'Hết hạn nộp:'
-            @job_expiry_date = detail.parent.children.last.text # Job expiry date
-          end
-        end
+        Job Information
+        job_name = doc_job_details.xpath("//div[@class='LeftJobCB']/div[@class='top-job']/div[@class='top-job-info']/h1").text.strip # Job name
+        job_description = doc_job_details.xpath("//div[@class='MarBot20']").text.strip # Job description
+
+        job_location = doc_job_details.xpath("//ul[@class='DetailJobNew']/li/p[span/text()='Nơi làm việc: ']/b[@itemprop='jobLocation']").text.strip
+
+        job_level = doc_job_details.xpath("//ul[@class='DetailJobNew']/li/p[span/text()='Cấp bậc: ']/label[@itemprop='occupationalCategory']").text.strip
+
+        job_experience = doc_job_details.xpath("//ul[@class='DetailJobNew']/li/p[span/text()='Kinh nghiệm: ']/text()")
+
+        job_salary = doc_job_details.xpath("//ul[@class='DetailJobNew']/li/p[span/text()='Lương: ']/label[@itemprop='baseSalary']").text.strip + " " +
+                     doc_job_details.xpath("//ul[@class='DetailJobNew']/li/p[span/text()='Lương: ']/label[@itemprop='salaryCurrency']").text.strip
+
+        job_category = doc_job_details.xpath("//ul[@class='DetailJobNew']/li/p[span/text()='Ngành nghề: ']/b/a[@itemprop='industry']").text.strip
+
+        job_expiry_date = doc_job_details.xpath("//ul[@class='DetailJobNew']/li/p[span/text()='Hết hạn nộp: ']/text()")
 
         Job.new(name: job_name, description: job_description,
-                  salary: @job_salary,
-                  city: City.find_by_name(@job_location),
-                  level: @job_level, experience: @job_experience, status: 0).save
+                salary: job_salary,
+                city: City.find_by_name(job_location),
+                level: job_level, experience: job_experience, status: 0,
+                expiry_date: job_expiry_date.to_datetime.strftime('%Q')).save
 
-        @job_category.split(',').each do |job_category|
-          JobCategory.new(job: Job.find_by_name(job_name), category: Category.find_by_name(job_category)).save
+        job_category.split(',').each do |category|
+          JobCategory.new(job: Job.find_by_name(job_name), category: Category.find_by_name(category)).save
         end
       end
-      url = doc_new_jobs.css('div.paginationTwoStatus a.right')[0]['href']
+      url = doc_new_jobs.xpath("//div[@class='paginationTwoStatus']/a[@class='right']/@href").to_s
     end
   end
 end