Spider component guide, run vr against previews

We can’t easily get a list of URLs for a component guide. Instead use
the wraith spider feature and crawl the review domain’s component
guide. Exclude paths that don’t start with /component-guide and only
compare paths that end with `/preview` to limit the number of pages and
speed up the test run.

* Include rake tasks for running locally
* Use Heroku runner in app

.gitignore

@@ -1,3 +1,4 @@
 results/visual
 config/tmp*
+config/spider_paths*
 node_modules/

app.rb

@@ -13,6 +13,11 @@
   end
 
   environment = payload['deployment']['environment']
-  paths = GovukVisualRegression::VisualDiff::DocumentTypes.new.type_paths('statistics')
-  GovukVisualRegression::VisualDiff::HerokuRunner.new(paths: paths, environment: environment).run
+  review_domain = "https://#{environment}.herokuapp.com"
+  live_domain = "https://#{environment.gsub(/\-pr\-\d+$/, '')}.herokuapp.com"
+  surge_domain = "#{environment}.surge.sh"
+
+  GovukVisualRegression::VisualDiff::Runner.new(review_domain: review_domain).spider_component_guide
+  paths = GovukVisualRegression::VisualDiff::SpiderPaths.component_preview_paths
+  GovukVisualRegression::VisualDiff::HerokuRunner.new(paths: paths, review_domain: review_domain, live_domain: live_domain, surge_domain: surge_domain).run
 end

config/wraith.yaml

@@ -5,7 +5,6 @@ browser:
 directory: results/visual
 screen_widths:
   - 320x5000
-  - 600x4000
   - 1080x3000
 resize_or_reload: 'resize'
 mode: diffs_first

lib/govuk_visual_regression.rb

@@ -13,6 +13,10 @@ def self.wraith_config_template
     config_file 'wraith.yaml'
   end
 
+  def self.spider_paths
+    config_file 'spider_paths.yml'
+  end
+
   def self.config_file(filename)
     File.expand_path(root_dir + "/config/#{filename}")
   end

lib/govuk_visual_regression/tasks/rakefile.rake

@@ -6,6 +6,14 @@ def load_paths
   YAML.load(open(ENV.fetch("URI")))
 end
 
+def review_domain
+  ENV.fetch("REVIEW_DOMAIN")
+end
+
+def live_domain
+  ENV.fetch("LIVE_DOMAIN")
+end
+
 namespace :diff do
   desc 'Set env var `URI` with location of a yaml file containing paths to diff'
   task visual: ['config:pre_flight_check'] do |_t, args|
@@ -20,6 +28,16 @@ namespace :diff do
     GovukVisualRegression::VisualDiff::Runner.new(paths: paths).run
   end
 
+  desc 'Set env var `REVIEW_DOMAIN` to the domain hosting the newer component guide and `LIVE_DOMAIN` to compare with'
+  task component_guide: ['spider:component_guide'] do |_t, args|
+    paths = GovukVisualRegression::VisualDiff::SpiderPaths.component_preview_paths
+    if paths.any?
+      GovukVisualRegression::VisualDiff::Runner.new(paths: paths, review_domain: review_domain, live_domain: live_domain).run
+    else
+      puts "No paths found"
+    end
+  end
+
   desc "clears the results directory"
   task :clear_results do
     puts "---> Clearing results directory"
@@ -28,6 +46,13 @@ namespace :diff do
   end
 end
 
+namespace :spider do
+  desc 'Set env var `REVIEW_DOMAIN` to the domain hosting the component guide'
+  task component_guide: ['config:pre_flight_check'] do |_t, args|
+    GovukVisualRegression::VisualDiff::Runner.new(review_domain: review_domain).spider_component_guide
+  end
+end
+
 namespace :config do
   desc "Checks that dependencies are in place"
   task :pre_flight_check do

lib/govuk_visual_regression/visual_diff.rb

@@ -3,6 +3,8 @@ module VisualDiff
     autoload :Runner, 'govuk_visual_regression/visual_diff/runner'
     autoload :HerokuRunner, 'govuk_visual_regression/visual_diff/heroku_runner'
     autoload :WraithConfig, 'govuk_visual_regression/visual_diff/wraith_config'
+    autoload :WraithSpiderComponentGuideConfig, 'govuk_visual_regression/visual_diff/wraith_spider_component_guide_config'
     autoload :DocumentTypes, 'govuk_visual_regression/visual_diff/document_types'
+    autoload :SpiderPaths, 'govuk_visual_regression/visual_diff/spider_paths'
   end
 end

lib/govuk_visual_regression/visual_diff/heroku_runner.rb

@@ -1,13 +1,20 @@
 module GovukVisualRegression
   module VisualDiff
     class HerokuRunner < Runner
+      def initialize(paths: [], review_domain: nil, live_domain: nil, surge_domain: nil, kernel: Kernel)
+        @paths = paths
+        @kernel = kernel
+        @review_domain = review_domain
+        @live_domain = live_domain
+        @surge_domain = surge_domain
+      end
+
       def install_surge
         @kernel.system "yarn global add surge"
       end
 
       def upload_to_surge
-        surge_domain = @environment ? @environment : "govuk-vr"
-        @kernel.system "surge --project results/visual/ --domain #{surge_domain}.surge.sh"
+        @kernel.system "surge --project results/visual/ --domain #{@surge_domain}"
       end
 
       def run

lib/govuk_visual_regression/visual_diff/runner.rb

@@ -1,15 +1,25 @@
 module GovukVisualRegression
   module VisualDiff
     class Runner
-      def initialize(paths:, environment: nil, kernel: Kernel)
+      def initialize(paths: [], review_domain: nil, live_domain: nil, kernel: Kernel)
         @paths = paths
         @kernel = kernel
-        @environment = environment
+        @review_domain = review_domain
+        @live_domain = live_domain
+      end
+
+      def spider_component_guide
+        wraith_config = WraithSpiderComponentGuideConfig.new(review_domain: @review_domain)
+        wraith_config.write
+
+        cmd = "wraith spider #{wraith_config.location}"
+        puts "---> Running component guide spider on #{@review_domain}"
+        puts "running: #{cmd}"
+        @kernel.system cmd
       end
 
       def run
-        review_domain = @environment ? "https://#{@environment}.herokuapp.com" : nil
-        wraith_config = WraithConfig.new(paths: @paths, review_domain: review_domain)
+        wraith_config = WraithConfig.new(paths: @paths, review_domain: @review_domain, live_domain: @live_domain)
         wraith_config.write
 
         cmd = "wraith capture #{wraith_config.location}"

lib/govuk_visual_regression/visual_diff/spider_paths.rb

@@ -0,0 +1,16 @@
+require 'yaml'
+
+module GovukVisualRegression
+  module VisualDiff
+    module SpiderPaths
+      def self.paths
+        YAML.load_file(GovukVisualRegression.spider_paths)['paths']
+      end
+
+      # Only test component previews, not the guide itself
+      def self.component_preview_paths
+        paths.values.select { |v| v.match(/preview$/) }
+      end
+    end
+  end
+end

lib/govuk_visual_regression/visual_diff/wraith_config.rb

@@ -1,5 +1,4 @@
 require 'yaml'
-require 'securerandom'
 
 module GovukVisualRegression
   module VisualDiff
@@ -9,11 +8,11 @@ class WraithConfig
       attr_reader :review_domain
       attr_reader :live_domain
 
-      def initialize(paths:, review_domain: nil, live_domain: nil)
+      def initialize(paths: [], review_domain: nil, live_domain: nil)
         @paths = paths
         @live_domain = live_domain
         @review_domain = review_domain
-        @location = GovukVisualRegression.config_file("tmp_wraith_config.yaml")
+        @location = GovukVisualRegression.config_file(temporary_config_file_name)
       end
 
       def config
@@ -51,6 +50,10 @@ def path_would_break_wraith?(path)
       def path_config_name(path)
         path.gsub('/', '_')
       end
+
+      def temporary_config_file_name
+        "tmp_wraith_config.yaml"
+      end
     end
   end
 end

lib/govuk_visual_regression/visual_diff/wraith_spider_component_guide_config.rb

@@ -0,0 +1,23 @@
+module GovukVisualRegression
+  module VisualDiff
+    class WraithSpiderComponentGuideConfig < WraithConfig
+      def config
+        config = YAML.load_file(GovukVisualRegression.wraith_config_template)
+        config["domains"].delete("live")
+        config["domains"]["review"] = "#{review_domain}/component-guide" if review_domain
+
+        # http://bbc-news.github.io/wraith/#Spiderfunctionality
+        config["imports"] = "spider_paths.yml"
+
+        # Skip pages that don't begin with /component-guide
+        config["spider_skips"] = [/^\/(?!component\-guide)/]
+        config.delete("paths")
+        config
+      end
+
+      def temporary_config_file_name
+        "tmp_wraith_spider_component_guide_config.yaml"
+      end
+    end
+  end
+end

spec/govuk_visual_regression/visual_diff/runner_spec.rb

@@ -12,7 +12,7 @@
     end
 
     it "executes wraith with the appropriate config" do
-      expect(config_handler_klass).to receive(:new).with(paths: ["/government/stats/foo", "/government/stats/bar"], review_domain: nil)
+      expect(config_handler_klass).to receive(:new).with(paths: ["/government/stats/foo", "/government/stats/bar"], review_domain: nil, live_domain: nil)
       expect(config_handler).to receive(:write)
       expect(kernel).to receive(:system).with("wraith capture #{config_handler.location}")
       expect(config_handler).to receive(:delete)