Merge pull request #278 from alphagov/port-metatags

Port Analytics meta tags component

CHANGELOG.md

@@ -1,3 +1,6 @@
+* Add the Meta tags component. This component should be used in place of the
+  "analytics meta tags" component in static. They have the same behaviour.
+
 # 6.6.0
 
 * Show all mainstream browse pages in the sidebar (#273)

app/views/govuk_publishing_components/components/_meta_tags.html.erb

@@ -0,0 +1,5 @@
+<% meta_tags = GovukPublishingComponents::Presenters::MetaTags.new(content_item, local_assigns).meta_tags %>
+
+<% meta_tags.each do |name, content| %>
+  <meta name="<%= name %>" content="<%= content %>">
+<% end %>

app/views/govuk_publishing_components/components/docs/meta_tags.yml

@@ -0,0 +1,25 @@
+name: Meta Tags
+description: Meta tags to provide analytics information about the current page
+body: |
+  This takes a content-store links hash like object which it can then turn into
+  the correct analytics identifier metadata tags.
+
+  The code which reads the meta tags can be found <a href="https://github.com/alphagov/static/blob/master/app/assets/javascripts/analytics/static-analytics.js#L76-L96">in static-analytics.js</a>.
+accessibility_criteria: |
+  The analytics meta tags component should not be visible to any users.
+examples:
+  with_organisations:
+    data:
+      content_item:
+        links:
+          organisations:
+          - analytics_identifier: D1
+          - analytics_identifier: D3
+          worldwide_organisations:
+          - analytics_identifier: EO3
+  with_world_locations:
+    data:
+      content_item:
+        links:
+          world_locations:
+          - analytics_identifier: WL3

lib/govuk_publishing_components.rb

@@ -7,6 +7,7 @@
 require "govuk_publishing_components/presenters/content_breadcrumbs_based_on_parent"
 require "govuk_publishing_components/presenters/content_breadcrumbs_based_on_taxons"
 require "govuk_publishing_components/presenters/services"
+require "govuk_publishing_components/presenters/meta_tags"
 require "govuk_publishing_components/presenters/taxonomy_navigation"
 require "govuk_publishing_components/presenters/rummager_taxonomy_sidebar_links"
 require "govuk_publishing_components/presenters/curated_taxonomy_sidebar_links"

lib/govuk_publishing_components/presenters/meta_tags.rb

@@ -0,0 +1,141 @@
+module GovukPublishingComponents
+  module Presenters
+    class MetaTags
+      attr_reader :content_item, :details, :links, :local_assigns
+
+      def initialize(content_item, local_assigns)
+        # We have to call deep_symbolize_keys because we're often dealing with a
+        # parsed JSON document which will have string keys by default, but our
+        # components use symbol keys and we want consistency.
+        @content_item = content_item.to_h.deep_symbolize_keys
+        @details = @content_item[:details] || {}
+        @links = @content_item[:links] || {}
+        @local_assigns = local_assigns
+      end
+
+      def meta_tags
+        meta_tags = {}
+        meta_tags = add_core_tags(meta_tags)
+        meta_tags = add_organisation_tags(meta_tags)
+        meta_tags = add_political_tags(meta_tags)
+        meta_tags = add_taxonomy_tags(meta_tags)
+        meta_tags = add_step_by_step_tags(meta_tags)
+        meta_tags
+      end
+
+    private
+
+      def add_core_tags(meta_tags)
+        meta_tags["govuk:format"] = content_item[:document_type] if content_item[:document_type]
+        meta_tags["govuk:schema-name"] = content_item[:schema_name] if content_item[:schema_name]
+
+        user_journey_stage = content_item[:user_journey_document_supertype]
+        meta_tags["govuk:user-journey-stage"] = user_journey_stage if user_journey_stage
+
+        navigation_document_type = content_item[:navigation_document_supertype]
+        meta_tags["govuk:navigation-document-type"] = navigation_document_type if navigation_document_type
+
+        meta_tags["govuk:content-id"] = content_item[:content_id] if content_item[:content_id]
+        meta_tags["govuk:withdrawn"] = "withdrawn" if content_item[:withdrawn_notice].present?
+        meta_tags["govuk:content-has-history"] = "true" if has_content_history?
+        meta_tags["govuk:static-analytics:strip-postcodes"] = "true" if should_strip_postcode_pii?(content_item, local_assigns)
+
+        meta_tags
+      end
+
+      def add_organisation_tags(meta_tags)
+        organisations = []
+        organisations += links[:organisations] || []
+        organisations += links[:worldwide_organisations] || []
+        organisations_content = organisations.map { |link| "<#{link[:analytics_identifier]}>" }.uniq.join
+        meta_tags["govuk:analytics:organisations"] = organisations_content if organisations.any?
+
+        world_locations = links[:world_locations] || []
+        world_locations_content = world_locations.map { |link| "<#{link[:analytics_identifier]}>" }.join
+        meta_tags["govuk:analytics:world-locations"] = world_locations_content if world_locations.any?
+
+        meta_tags
+      end
+
+      def add_political_tags(meta_tags)
+        if details.key?(:political) && details.key?(:government)
+          political_status = "non-political"
+          if details[:political]
+            political_status = details[:government][:current] ? "political" : "historic"
+          end
+
+          meta_tags["govuk:political-status"] = political_status
+          meta_tags["govuk:publishing-government"] = details[:government][:slug]
+        end
+
+        meta_tags
+      end
+
+      def add_taxonomy_tags(meta_tags)
+        themes = root_taxon_slugs(content_item)
+        meta_tags["govuk:themes"] = themes.to_a.sort.join(', ') unless themes.empty?
+
+        taxons = if content_item[:document_type] == 'taxon'
+                   [content_item]
+                 else
+                   links[:taxons] || []
+                 end
+
+        taxons.sort_by! { |taxon| taxon[:title] }
+        taxon_slugs_without_theme = taxons.map do |taxon|
+          base_path = taxon[:base_path] || ""
+          slug_without_theme = base_path[%r{/[^/]+/(.+)}, 1]
+          # Return the slug without the theme, or in the special case of a root taxon,
+          # just return the full slug (because it doesn't have a slug beneath the theme)
+          slug_without_theme || base_path.sub(%r(^/), '')
+        end
+        taxon_ids = taxons.map { |taxon| taxon[:content_id] }
+
+        meta_tags["govuk:taxon-id"] = taxon_ids.first unless taxon_ids.empty?
+        meta_tags["govuk:taxon-ids"] = taxon_ids.join(',') unless taxon_ids.empty?
+        meta_tags["govuk:taxon-slug"] = taxon_slugs_without_theme.first unless taxon_slugs_without_theme.empty?
+        meta_tags["govuk:taxon-slugs"] = taxon_slugs_without_theme.join(',') unless taxon_slugs_without_theme.empty?
+        meta_tags
+      end
+
+      def add_step_by_step_tags(meta_tags)
+        stepnavs = links[:part_of_step_navs] || []
+        stepnavs_content = stepnavs.map { |stepnav| stepnav[:content_id] }.join(",")
+        meta_tags["govuk:stepnavs"] = stepnavs_content if stepnavs_content.present?
+        meta_tags
+      end
+
+      def has_content_history?
+        (content_item[:public_updated_at] && details[:first_public_at] && content_item[:public_updated_at] != details[:first_public_at]) ||
+          (details[:change_history] && details[:change_history].size > 1)
+      end
+
+      def root_taxon_slugs(content_item)
+        root_taxon_set = Set.new
+
+        links = content_item[:links]
+        # Taxons will have :parent_taxons, but content items will have :taxons
+        parent_taxons = links[:parent_taxons] || links[:taxons] unless links.nil?
+
+        if parent_taxons.blank?
+          root_taxon_set << content_item[:base_path].sub(%r(^/), '') if content_item[:document_type] == 'taxon'
+        else
+          parent_taxons.each do |parent_taxon|
+            root_taxon_set += root_taxon_slugs(parent_taxon)
+          end
+        end
+
+        root_taxon_set
+      end
+
+      def should_strip_postcode_pii?(content_item, local_assigns)
+        # allow override if we explicitly want to strip pii (or not) regardless of
+        # document_type
+        return local_assigns[:strip_postcode_pii] if local_assigns.key?(:strip_postcode_pii)
+
+        formats_that_might_include_postcodes = %w[smart_answer search]
+        formats_that_might_include_postcodes.include?(content_item[:document_type])
+      end
+    end
+  end
+end