Create Transfer Processing Queue with tests

** Why are these changes being introduced:

* The first step of the Transfer processing workflow is to allow staff
  to identify which Transfer they want to process (out of all available)
  and get to the page that will allow them to process the submitted
  files.

** Relevant ticket(s):

* https://mitlibraries.atlassian.net/browse/ETD-276

** How does this address that need:

* This defines a transfer selection screen (/transfer/select) where
  staff can see the list of available transfer records. This display can
  be filtered by graduation month (or by arbitrary user input). When the
  user clicks on any transfer in the list, they are taken to the (blank)
  detail page for that transfer. Future work will further develop that
  interface.
* This PR also includes relevant tests for the navigation, the new
  path, and the existing ability model.

** Document any side effects to this change:

* Part of the UI for this transfer selection screen is enabled by a
  jQuery plugin, DataTables. This plugin, while very useful out of the
  box, does increase our reliance on the jQuery ecosystem. A future
  discussion in EngX may lead to us needing to re-develop this screen
  using either Vue or native Javascript.

app/controllers/transfer_controller.rb

@@ -26,6 +26,10 @@ def create
     end
   end
 
+  def select
+    @transfer = Transfer.all
+  end
+
   def show
     @transfer = Transfer.find(params[:id])
   end

app/models/ability.rb

@@ -66,6 +66,7 @@ def processor
     can :stats, Thesis
 
     can :read, Transfer
+    can :select, Transfer
     can :read, Hold
   end
 

app/views/layouts/_site_nav.html.erb

@@ -17,6 +17,9 @@
             <% if can? :create, Transfer %>
               <%= nav_link_to("Transfer theses", new_transfer_path) %>
             <% end %>
+            <% if can? :select, Transfer %>
+              <%= nav_link_to("Process transfers", transfer_select_path) %>
+            <% end %>
             <% if can? :create, Registrar %>
               <%= nav_link_to("Upload CSV", new_registrar_path) %>
             <% end %>

app/views/transfer/_empty.html.erb

@@ -0,0 +1,3 @@
+<tr class="empty">
+  <td colspan="6">There were no transfers matching your parameters.</td>
+</tr>

app/views/transfer/_transfer.html.erb

@@ -0,0 +1,8 @@
+<tr>
+  <td data-sort="<%= transfer.created_at %>"><%= link_to transfer.created_at.in_time_zone('Eastern Time (US & Canada)').strftime('%b %-d, %Y<br>%l:%M %p').html_safe, url_for(transfer) %></td>
+  <td data-sort="<%= transfer.grad_date %>"><%= transfer.graduation_month[...3] %> <%= transfer.graduation_year %></td>
+  <td><%= transfer.department.name_dw %></td>
+  <td><%= transfer.user.display_name %></td>
+  <td><%= transfer.files.count %></td>
+  <td><%= transfer.note.present? ? "<span title='#{transfer.note}'>#{transfer.note[..10]}...</span>".html_safe : "" %></td>
+</tr>

app/views/transfer/select.html.erb

@@ -0,0 +1,63 @@
+<%= content_for(:title, "Transfer Processing | MIT Libraries") %>
+
+<% content_for :additional_js do %>
+  <script src="https://cdn.datatables.net/1.10.24/js/jquery.dataTables.min.js"></script>
+<% end %>
+
+<link href="https://cdn.datatables.net/1.10.24/css/jquery.dataTables.min.css" rel="stylesheet">
+
+<h3 class="title title-page">Transfer Processing Queue</h3>
+
+<div id="term-list" class="filter-row">
+  <button data-filter="*">Show<br>all</button>
+</div>
+
+<table class="table" id="transferQueue">
+  <thead>
+    <tr>
+      <th scope="col">Transfer date</th>
+      <th scope="col">Degree date</th>
+      <th scope="col">Department</th>
+      <th scope="col">Dept. Admin</th>
+      <th scope="col">Files</th>
+      <th scope="col">Notes</th>
+    </tr>
+  </thead>
+  <tbody>
+    <%= render(partial: 'transfer/transfer', collection: @transfers) || render('empty') %>
+  </tbody>
+</table>
+
+<script type="text/javascript">
+$(document).ready( function () {
+  if( document.getElementById('transferQueue').getElementsByClassName('empty').length === 0 ) {
+    var table = $('#transferQueue').DataTable({
+      "order": [[ 1, "asc" ]]
+    });
+
+    // Populate filter buttons with found values
+    var terms = [...new Set( table.columns(1).data()[0] )];
+    terms.forEach(element => {
+      document
+        .getElementById("term-list")
+        .insertAdjacentHTML("beforeend", `
+        <button data-filter="${element}">${element.replace(' ', '<br>')}</button>
+      `);
+    });
+
+    // Perform filtering when buttons are clicked
+    $(".filter-row button").click(function() {
+      var needle = $(this).data("filter");
+      $.fn.dataTable.ext.search.push(
+        function( settings, data, dataIndex ) {
+          return ( data[1] === needle || needle === "*" )
+            ? true
+            : false
+        }
+      );
+      table.draw();
+      $.fn.dataTable.ext.search.pop();
+    });
+  }
+});
+</script>

app/views/transfer/show.html.erb

@@ -1 +1,7 @@
-<%= content_for(:title, "Thesis Transfer Submission | MIT Libraries") %>
+<%= content_for(:title, "Transfer Processing | MIT Libraries") %>
+
+<h3 class="title title-page">Transfer file list</h3>
+
+<p><%= link_to "Back to Transfer queue", transfer_select_path %></p>
+
+<p>This will be the display of all files in this Transfer, for processing into Thesis records.</p>

config/routes.rb

@@ -45,6 +45,7 @@
   }
 
   get 'transfer/confirm', to: 'transfer#confirm', as: 'transfer_confirm'
+  get 'transfer/select', to: 'transfer#select', as: 'transfer_select'
   resources :transfer, only: [:new, :create, :show]
 
   devise_scope :user do

test/controllers/transfer_controller_test.rb

@@ -110,4 +110,60 @@ class TransferControllerTest < ActionDispatch::IntegrationTest
     assert_match "Error saving transfer", response.body
     assert_equal original_count, Transfer.count
   end
+
+  # ~~~~~~~~~~~~~~~~~~~~~~~~~~ transfer processing queue ~~~~~~~~~~~~~~~~~~~~~
+  test 'transfer processing queue exists' do
+    sign_in users(:admin)
+    get transfer_select_path
+    assert_response :success
+  end
+
+  test 'anonymous users cannot see transfer queue' do
+    # Note that nobody signed in.
+    get transfer_select_path
+    assert_response :redirect
+  end
+
+  test 'basic users cannot see transfer queue' do
+    sign_in users(:basic)
+    get transfer_select_path
+    assert_redirected_to '/'
+    follow_redirect!
+    assert_select 'div.alert', text: 'Not authorized.', count: 1
+  end
+
+  test 'transfer submitters cannot see transfer queue' do
+    sign_in users(:transfer_submitter)
+    get transfer_select_path
+    assert_redirected_to '/'
+    follow_redirect!
+    assert_select 'div.alert', text: 'Not authorized.', count: 1
+  end
+
+  test 'processors can see transfer queue' do
+    sign_in users(:processor)
+    get transfer_select_path
+    assert_response :success
+  end
+
+  test 'thesis admins can set transfer queue' do
+    sign_in users(:thesis_admin)
+    get transfer_select_path
+    assert_response :success
+  end
+
+  test 'admins can see transfer queue' do
+    sign_in users(:admin)
+    get transfer_select_path
+    assert_response :success
+  end
+
+  test 'transfer processing queue has links to transfer pages' do
+    sign_in users(:thesis_admin)
+    get transfer_select_path
+    expected_transfers = Transfer.all
+    expected_transfers.each do |t|
+      assert @response.body.include? transfer_path(t)
+    end
+  end
 end

test/fixtures/transfers.yml

@@ -20,8 +20,3 @@ alsovalid:
   department: one
   grad_date: 2020-05-01
   user: thesis_admin
-
-baduser:
-  department: one
-  grad_date: 2020-05-01
-  user: invalid

test/integration/nav_test.rb

@@ -68,6 +68,14 @@ def teardown
     end
   end
 
+  test 'transfer selection nav' do
+    mock_auth(users(:admin))
+    get transfer_select_path
+    assert_select('.current') do |value|
+      assert(value.text.include?('Process transfers'))
+    end
+  end
+
   # Basic user navigation
   test 'basic navigation' do
     mock_auth(users(:basic))
@@ -81,6 +89,7 @@ def teardown
       assert_select "a[href=?]", process_path, count: 0
       assert_select "a[href=?]", stats_path, count: 0
       assert_select "a[href=?]", new_transfer_path, count: 0
+      assert_select "a[href=?]", transfer_select_path, count: 0
       assert_select "a[href=?]", new_registrar_path, count: 0
       assert_select "a[href=?]", harvest_path, count: 0
       assert_select "a[href=?]", admin_root_path, count: 0
@@ -100,6 +109,7 @@ def teardown
       # Navigation should not include:
       assert_select "a[href=?]", process_path, count: 0
       assert_select "a[href=?]", stats_path, count: 0
+      assert_select "a[href=?]", transfer_select_path, count: 0
       assert_select "a[href=?]", new_registrar_path, count: 0
       assert_select "a[href=?]", harvest_path, count: 0
       assert_select "a[href=?]", admin_root_path, count: 0
@@ -115,6 +125,7 @@ def teardown
       assert_select "a[href=?]", root_path
       assert_select "a[href=?]", thesis_start_path
       # assert_select "a[href=?]", new_transfer_path
+      assert_select "a[href=?]", transfer_select_path
       assert_select "a[href=?]", process_path
       assert_select "a[href=?]", stats_path
       assert_select "a[href=?]", new_registrar_path, count: 0
@@ -132,6 +143,7 @@ def teardown
       assert_select "a[href=?]", root_path
       assert_select "a[href=?]", thesis_start_path
       assert_select "a[href=?]", new_transfer_path
+      assert_select "a[href=?]", transfer_select_path
       assert_select "a[href=?]", process_path
       assert_select "a[href=?]", stats_path
       assert_select "a[href=?]", new_registrar_path
@@ -149,6 +161,7 @@ def teardown
       assert_select "a[href=?]", root_path
       assert_select "a[href=?]", thesis_start_path
       assert_select "a[href=?]", new_transfer_path
+      assert_select "a[href=?]", transfer_select_path
       assert_select "a[href=?]", process_path
       assert_select "a[href=?]", stats_path
       assert_select "a[href=?]", new_registrar_path

test/models/transfer_test.rb

@@ -28,7 +28,9 @@ class TransferTest < ActiveSupport::TestCase
   end
 
   test 'needs valid user' do
-    @transfer = transfers(:baduser)
+    @transfer = transfers(:valid)
+    assert @transfer.valid?
+    @transfer.user = nil
     assert @transfer.invalid?
   end