Adding a state machine to manage states and transitions

Gemfile

@@ -94,6 +94,7 @@ gem "omniauth-cas"
 gem 'ezid-client'
 gem 'sprockets-es6'
 gem 'browse-everything', github: 'projecthydra-labs/browse-everything'
+gem 'aasm'
 source 'https://rails-assets.org' do
   gem 'rails-assets-babel-polyfill'
 end

Gemfile.lock

@@ -133,6 +133,7 @@ GEM
   remote: https://rubygems.org/
   remote: https://rails-assets.org/
   specs:
+    aasm (4.5.0)
     actionmailer (4.2.4)
       actionpack (= 4.2.4)
       actionview (= 4.2.4)
@@ -784,6 +785,7 @@ PLATFORMS
   ruby
 
 DEPENDENCIES
+  aasm
   active-fedora!
   activefedora-aggregation!
   browse-everything!

app/models/concerns/common_metadata.rb

@@ -41,7 +41,7 @@ def apply_remote_metadata
     end
 
     def check_completion
-      complete_record if self.state_changed? && state == 'complete'
+      complete_record if state_changed? && state == 'complete'
     end
 
     private

app/models/solr_document.rb

@@ -29,6 +29,10 @@ def state
     Array(self[Solrizer.solr_name("state")]).first
   end
 
+  def type
+    self['active_fedora_model_ssi']
+  end
+
   def viewing_hint
     Array(self[Solrizer.solr_name("viewing_hint")]).first
   end

app/models/state_workflow.rb

@@ -0,0 +1,56 @@
+# State-based workflow: The primary workflow is to start at pending, and
+# progress through metadata_review and final_review to complete.  There are
+# two exceptional workflows: between complete/takedown (for issues requiring
+# an item be suppressed), and between complete/flagged (for issues where an
+# item can remain accessible).
+class StateWorkflow
+  include AASM
+
+  def initialize(state)
+    aasm.current_state = state.to_sym unless state.nil?
+  end
+
+  aasm do
+    state :pending, initial: true
+    state :metadata_review
+    state :final_review
+    state :complete
+    state :takedown
+    state :flagged
+
+    # ingest workflow
+    event :finalize_digitization do
+      transitions from: :pending, to: :metadata_review
+    end
+    event :finalize_metadata do
+      transitions from: :metadata_review, to: :final_review
+    end
+    event :complete do
+      transitions from: :final_review, to: :complete
+    end
+
+    # takedown/restore workflow
+    event :takedown do
+      transitions from: :complete, to: :takedown
+    end
+    event :restore do
+      transitions from: :takedown, to: :complete
+    end
+
+    # flag/unflag workflow
+    event :flag do
+      transitions from: :complete, to: :flagged
+    end
+    event :unflag do
+      transitions from: :flagged, to: :complete
+    end
+  end
+
+  def suppressed?
+    pending? || metadata_review? || final_review? || takedown?
+  end
+
+  def valid_transitions
+    aasm.states(permitted: true).map(&:name)
+  end
+end

app/presenters/curation_concerns_show_presenter.rb

@@ -1,7 +1,7 @@
 class CurationConcernsShowPresenter < CurationConcerns::WorkShowPresenter
-  delegate :date_created, :viewing_hint, :viewing_direction, :state, :identifier, :workflow_note, to: :solr_document
+  delegate :date_created, :viewing_hint, :viewing_direction, :state, :type, :identifier, :workflow_note, to: :solr_document
 
   def state_badge
-    StateBadge.new(solr_document).render
+    StateBadge.new(type, state).render
   end
 end

app/presenters/file_set_presenter.rb

@@ -5,8 +5,4 @@ class FileSetPresenter < CurationConcerns::FileSetPresenter
   def label
     nil
   end
-
-  def state_badge
-    StateBadge.new(solr_document).render
-  end
 end

app/presenters/state_badge.rb

@@ -1,41 +1,63 @@
 class StateBadge
+  include ActionView::Context
   include ActionView::Helpers::TagHelper
 
-  def initialize(solr_document)
-    @solr_document = solr_document
+  def initialize(type, state = nil)
+    @type = type.underscore
+    @state = StateWorkflow.new state
   end
 
   def render
-    content_tag(:span, link_title, title: link_title, class: "label #{dom_label_class}")
+    label = I18n.t("state.#{current_state}.label")
+    content_tag(:span, label, title: label, class: "label #{dom_label_class}")
+  end
+
+  def render_buttons
+    html = render_radio_button(current_state, checked: true)
+    @state.valid_transitions.each do |valid_state|
+      html += render_radio_button(valid_state)
+    end
+    html
+  end
+
+  def render_hidden
+    tag :input, id: "#{field_id}", name: field_name, type: :hidden, value: current_state
   end
 
   private
 
-    def dom_label_class
-      if complete?
-        'label-success'
-      elsif review?
-        'label-info'
-      else
-        'label-warning'
+    def render_radio_button(state, checked = false)
+      content_tag :label, class: 'radio' do
+        tag(:input, id: field_id(state), name: field_name, type: :radio, value: state, checked: checked) +
+          content_tag(:span, I18n.t("state.#{state}.label"), class: "label #{dom_label_class(state)}", for: field_id(state)) +
+          " " + I18n.t("state.#{state}.desc")
       end
     end
 
-    def link_title
-      if complete?
-        'Complete'
-      elsif review?
-        'Review'
-      else
-        'Pending'
-      end
+    def dom_label_class(state = current_state)
+      state_classes[state]
+    end
+
+    def state_classes
+      @state_classes ||= {
+        pending: 'label-default',
+        metadata_review: 'label-info',
+        final_review: 'label-primary',
+        complete: 'label-success',
+        flagged: 'label-warning',
+        takedown: 'label-danger'
+      }
+    end
+
+    def current_state
+      @state.aasm.current_state
     end
 
-    def complete?
-      @solr_document.state == 'complete'
+    def field_name
+      "#{@type}[state]"
     end
 
-    def review?
-      @solr_document.state == 'review'
+    def field_id(state = current_state)
+      "#{@type}_state_#{state}"
     end
 end

app/validators/state_validator.rb

@@ -1,8 +1,17 @@
 class StateValidator < ActiveModel::Validator
-  delegate :validate, to: :inclusivity_validator
+  def validate(record)
+    inclusivity_validator.validate record
+    validate_transition record
+  end
 
   private
 
+    def validate_transition(record)
+      return unless record.state_changed? && !record.state_was.nil?
+      return if StateWorkflow.new(record.state_was).aasm.states(permitted: true).include? record.state.to_sym
+      record.errors.add :state, "Cannot transition from #{record.state_was} to #{record.state}"
+    end
+
     def inclusivity_validator
       @inclusivity_validator ||= ActiveModel::Validations::InclusionValidator.new(
         attributes: :state,
@@ -13,9 +22,12 @@ def inclusivity_validator
 
     def valid_states
       [
-        "complete",
         "pending",
-        "review"
+        "metadata_review",
+        "final_review",
+        "complete",
+        "flagged",
+        "takedown"
       ]
     end
 end

app/views/curation_concerns/base/_attributes.html.erb

@@ -12,12 +12,14 @@
       <%= @presenter.permission_badge %>
     </td>
   </tr>
-  <tr>
-    <th>State</th>
-    <td>
-      <%= @presenter.state_badge %>
-    </td>
-  </tr>
+  <% if @presenter.respond_to? :state_badge %>
+    <tr>
+      <th>State</th>
+      <td>
+        <%= @presenter.state_badge %>
+      </td>
+    </tr>
+  <% end %>
   <%= @presenter.attribute_to_html(:embargo_release_date) %>
   <%= @presenter.attribute_to_html(:lease_expiration_date) %>
   <%= @presenter.attribute_to_html(:rights) %>

app/views/curation_concerns/base/_form_state.html.erb

@@ -1,22 +1,10 @@
-<% unless curation_concern.new_record? %>
+<% if curation_concern.new_record? %>
+  <%= StateBadge.new(curation_concern.class.to_s).render_hidden %>
+<% else %>
   <fieldset id="set-state">
     <legend>State</legend>
     <div class="form-group">
-      <label class="radio">
-        <%= f.radio_button :state, 'pending', checked: curation_concern.state != 'complete' && curation_concern.state != 'review' %>
-        <%= f.label 'Pending', class: 'label label-warning', for: 'scanned_resource_state_pending' %>
-        In progress and suppressed from public display
-      </label>
-      <label class="radio">
-        <%= f.radio_button :state, 'review', checked: curation_concern.state == 'review' %>
-        <%= f.label 'Review', class: 'label label-info', for: 'scanned_resource_state_review' %>
-        In need of review
-      </label>
-      <label class="radio">
-        <%= f.radio_button :state, 'complete', checked: curation_concern.state == 'complete' %>
-        <%= f.label 'Complete', class: 'label label-success', for: 'scanned_resource_state_complete' %>
-        Finished work, visibility determined by Access Rights
-      </label>
+      <%= StateBadge.new(curation_concern.class.to_s, curation_concern.state).render_buttons %>
     </div>
   </fieldset>
 <% end %>

config/locales/en.yml

@@ -31,3 +31,22 @@ en:
           "": 'Single Page'
           non-paged: 'Non-Paged'
           facing-pages: 'Facing pages'
+  state:
+    pending:
+      label: 'Pending'
+      desc:  'Initial digitization, suppressed from display'
+    metadata_review:
+      label: 'Metadata Review'
+      desc:  'Awaiting metadata approval'
+    final_review:
+      label: 'Final Review'
+      desc:  'Awaiting final approval before being published'
+    complete:
+      label: 'Complete'
+      desc:  'Published and accessible according to access control rules'
+    flagged:
+      label: 'Flagged'
+      desc:  'In need of attention, but still accessible according to access rules'
+    takedown:
+      label: 'Takedown'
+      desc:  'Formerly-published but suppressed from display'

spec/factories/scanned_resources.rb

@@ -6,7 +6,7 @@
     use_and_reproduction "Jamie, remind me to give you a lesson in tying knots, sometime."
     description "900 years of time and space, and I’ve never been slapped by someone’s mother."
     visibility Hydra::AccessControls::AccessRight::VISIBILITY_TEXT_VALUE_PUBLIC
-    state "complete"
+    state "metadata_review"
 
     transient do
       user { FactoryGirl.create(:user) }

spec/features/edit_multi_volume_work_spec.rb

@@ -22,12 +22,12 @@
     fill_in 'multi_volume_work_portion_note', with: 'new portion note'
     fill_in 'multi_volume_work_description', with: 'new description'
     fill_in 'multi_volume_work_workflow_note', with: 'New note'
-    choose 'Complete'
+    choose 'Metadata Review'
 
     click_button 'Update Multi volume work'
     expect(page).to have_text("Test title (Multi Volume Work)")
     expect(page).to have_text("New note")
-    expect(page).to have_selector("span.label-success", "Complete")
+    expect(page).to have_selector("span.label-info", "Metadata Review")
   end
 
   scenario "User can create a new scanned resource attached to the multi-volume work" do

spec/features/edit_scanned_resource_spec.rb

@@ -20,11 +20,11 @@
       fill_in 'scanned_resource_source_metadata_identifier', with: '1234568'
       fill_in 'scanned_resource_portion_note', with: 'new portion note'
       fill_in 'scanned_resource_description', with: 'new description'
-      choose 'Pending'
+      choose 'Final Review'
 
       click_button 'Update Scanned resource'
       expect(page).to have_text("Test title (Scanned Resource)")
-      expect(page).to have_selector("span.label-warning", "Pending")
+      expect(page).to have_selector("span.label-primary", "Final Review")
     end
 
     scenario "User can add a new file" do

spec/features/new_scanned_resource_spec.rb

@@ -18,7 +18,7 @@
       click_button 'Create Scanned resource'
 
       expect(page).to have_selector("h1", "Test Title")
-      expect(page).to have_selector("span.label-warning", "Pending")
+      expect(page).to have_selector("span.label-default", "Pending")
       expect(page).to have_text("Jamie, remind me to give you a lesson in tying knots, sometime")
     end
   end

spec/models/scanned_resource_spec.rb

@@ -176,6 +176,7 @@
   end
 
   describe "#check_completion" do
+    subject { FactoryGirl.build(:scanned_resource, source_metadata_identifier: '12345', access_policy: 'Policy', use_and_reproduction: 'Statement', state: 'final_review') }
     before do
       subject.save
     end
@@ -192,7 +193,7 @@
       expect { subject.check_completion }.not_to change { ActionMailer::Base.deliveries.count }
     end
     it "does not complete record when state isn't 'complete'" do
-      subject.state = 'pending'
+      subject.state = 'final_review'
       expect(subject).not_to receive(:complete_record)
       expect { subject.check_completion }.not_to change { ActionMailer::Base.deliveries.count }
     end
@@ -204,6 +205,13 @@
       expect { subject.check_completion }.to change { ActionMailer::Base.deliveries.count }.by(1)
       expect(subject.identifier).to eq('1234')
     end
+    it "does not complete the record when the state transition is invalid" do
+      allow(subject).to receive("state_changed?").and_return true
+      subject.state = 'pending'
+      expect(subject).not_to receive(:complete_record)
+      expect { subject.check_completion }.not_to change { ActionMailer::Base.deliveries.count }
+      expect(subject.identifier).to eq(nil)
+    end
   end
 
   describe "#pending_uploads" do