Create view and related javascript for staging workflow deletion

src/api/app/assets/javascripts/webui2/application.js

@@ -41,3 +41,4 @@
 //= require webui2/jquery-ui.min.js
 //= require webui2/cm2/use-codemirror.js
 //= require webui2/package-view_file.js
+//= require webui2/staging_workflow.js

src/api/app/assets/javascripts/webui2/staging_workflow.js

@@ -0,0 +1,9 @@
+function setSpinnersForDeletion() { // jshint ignore:line
+  $("#staging-workflow-delete").on('ajax:beforeSend', function(){
+    $(this).find('.delete-spinner').removeClass('d-none');
+  });
+
+  $("#staging-workflow-delete").on('ajax:complete', function(){
+    $(this).find('.delete-spinner').addClass('d-none');
+  });
+}

src/api/app/views/webui2/webui/staging_workflows/_delete.html.haml

@@ -0,0 +1,28 @@
+%button.btn.btn-danger{ data: { toggle: 'modal', target: '#delete-staging-workflow' } }
+  Delete Staging Workflow
+
+.modal.fade{ id: 'delete-staging-workflow', tabindex: -1, role: 'dialog' }
+  .modal-dialog.modal-dialog-centered{ role: 'document' }
+    .modal-content
+      .modal-header
+        %h5.modal-title
+          Do you want to delete the staging workflow for #{project.name}?
+      .modal-body
+        %p Please confirm deletion of the staging workflow for #{project.name}
+        = form_tag staging_workflow_path, method: :delete, remote: true, id: 'staging-workflow-delete' do
+          - if @staging_workflow.staging_projects.any?
+            %p Check the staging projects you want to be deleted:
+            - @staging_workflow.staging_projects.each do |staging_project|
+              .form-check
+                = check_box_tag 'staging_project_ids[]', staging_project.id, false, class: 'form-check-input'
+                %label.form-check-label
+                  = staging_project.name
+          %br
+          .modal-footer
+            %i.fas.fa-spinner.fa-spin.delete-spinner.d-none
+            %button.btn.btn-sm.btn-outline-secondary.px-4{ data: { dismiss: 'modal' } }
+              Cancel
+            = submit_tag 'Delete', class: 'btn btn-sm btn-danger px-4'
+
+= content_for :ready_function do
+  setSpinnersForDeletion();

src/api/app/views/webui2/webui/staging_workflows/show.html.haml

@@ -12,6 +12,8 @@
             = link_to(edit_staging_workflow_path(@staging_workflow), class: 'nav-link') do
               %i.fas.fa-edit.text-info
               Edit Staging Workflow
+          - if policy(@staging_workflow).destroy?
+            = render(partial: 'webui2/webui/staging_workflows/delete', locals: { project: @project })
         %hr
 
         %table.table.table-striped.table-bordered.table-sm.dt-responsive.w-100#staging-projects-datatable