Allow processors to rename file attachments

Why are these changes being introduced:

* Duplicate filenames attached to a thesis cannot be preserved
* Sometimes we get duplicate filenames attached to a thesis
* We did not have a way to rename filenames in the application

Relevant ticket(s):

* https://mitlibraries.atlassian.net/browse/ETD-643

How does this address that need:

* Adds a form that allows processors to rename a file attachment

Document any side effects to this change:

* ability model initialize class was auto updated by rubocop to use
  a guard clause

app/controllers/file_controller.rb

@@ -0,0 +1,26 @@
+class FileController < ApplicationController
+  before_action :require_user
+  before_action :authenticate_user!
+  load_and_authorize_resource
+  protect_from_forgery with: :exception
+
+  def rename_form
+    @thesis = Thesis.find(params[:thesis_id])
+    @attachment = ActiveStorage::Attachment.find(params[:attachment_id])
+  end
+
+  def rename
+    thesis = Thesis.find(params[:thesis_id])
+    attachment = ActiveStorage::Attachment.find(params[:attachment_id])
+
+    attachment.blob.filename = params[:attachment][:filename]
+
+    if attachment.blob.save
+      flash[:success] = "#{thesis.title} file #{attachment.filename} been updated."
+    else
+      flash[:error] = "#{thesis.title} file was unable to be updated"
+    end
+
+    redirect_to thesis_process_path(thesis)
+  end
+end

app/models/ability.rb

@@ -6,20 +6,20 @@ def initialize(user)
     # See the documentation for details:
     # https://github.com/CanCanCommunity/cancancan/blob/develop/docs/Defining-Abilities.md
 
-    if user.present?
-      @user = user
-      # Admin users can do everything for all models
-      can :manage, :all if user.admin?
-
-      # Assign thesis_submitter rights directly to appropriate users as the
-      # process that follows will not pick them up as it is not an explicitly
-      # assigned role
-      transfer_submitter if user.submitter?
-
-      # This line matches users' roles with the functions defined below,
-      # giving them privileges accordingly.
-      send(@user.role.to_sym)
-    end
+    return unless user.present?
+
+    @user = user
+    # Admin users can do everything for all models
+    can :manage, :all if user.admin?
+
+    # Assign thesis_submitter rights directly to appropriate users as the
+    # process that follows will not pick them up as it is not an explicitly
+    # assigned role
+    transfer_submitter if user.submitter?
+
+    # This line matches users' roles with the functions defined below,
+    # giving them privileges accordingly.
+    send(@user.role.to_sym)
   end
 
   # The default; any logged-in user. The use case here is students uploading
@@ -91,6 +91,8 @@ def processor
     can :read, Transfer
     can :select, Transfer
     can :files, Transfer
+    can :rename_form, File
+    can :rename, File
 
     can :read, Hold
 

app/views/file/rename_form.html.erb

@@ -0,0 +1,4 @@
+<%= form_with model: @attachment, url: rename_file_path(thesis_id: @thesis, attachment_id: @attachment), method: 'post' do |form| %>
+  <%= form.text_field :filename, value: @attachment.filename %>
+  <%= form.submit %>
+<% end %>

app/views/thesis/_file_fields.html.erb

@@ -3,7 +3,10 @@
   <td>
     <%= link_to rails_blob_path(f.object, disposition: "inline"), target: :_blank do %>
       <%= f.object.blob.filename %>
-    <% end %>
+    <% end %>    
+  </td>
+  <td>
+    <%= link_to rename_file_form_path(thesis_id: @thesis, attachment_id: f.object) do %>Rename<% end %>
   </td>
   <td>
     <%= f.object.blob.created_at.in_time_zone('Eastern Time (US & Canada)').strftime('%b %-d, %Y<br>%l:%M %p').html_safe %>

app/views/thesis/process_theses.html.erb

@@ -297,6 +297,7 @@
         <tr>
           <th scope="col">Remove</th>
           <th scope="col">File</th>
+          <th scope="col">Rename file</th>
           <th scope="col">Received</th>
           <th scope="col">Purpose</th>
           <th scope="col">Description</th>

config/routes.rb

@@ -44,6 +44,10 @@
   get 'thesis/proquest_export_preview', to: 'thesis#proquest_export_preview', as: 'thesis_proquest_export_preview'
   get 'thesis/proquest_export', to: 'thesis#proquest_export', as: 'thesis_proquest_export'
   get 'thesis/reset_all_publication_errors', to: 'thesis#reset_all_publication_errors', as: 'reset_all_publication_errors'
+
+  # Blob file renaming
+  get 'file/rename/:thesis_id/:attachment_id', to: 'file#rename_form', as: 'rename_file_form'
+  post 'file/rename/:thesis_id/:attachment_id', to: 'file#rename', as: 'rename_file'
 
   resources :registrar, only: [:new, :create, :show]
   resources :thesis, only: [:new, :create, :edit, :show, :update]

test/controllers/files_controller_test.rb

@@ -0,0 +1,157 @@
+require 'test_helper'
+
+class FilesControllerTest < ActionDispatch::IntegrationTest
+  test 'anonymous users are prompted to log in when accessing rename form' do
+    @thesis = theses(:publication_review)
+    @attachment = @thesis.files.first
+    get "/file/rename/#{@thesis.id}/#{@attachment.id}"
+
+    assert_response :redirect
+    assert_redirected_to '/login'
+  end
+
+  test 'basic can not access file rename form' do
+    sign_in users(:basic)
+    @thesis = theses(:publication_review)
+    @attachment = @thesis.files.first
+    get "/file/rename/#{@thesis.id}/#{@attachment.id}"
+    assert_redirected_to '/'
+    follow_redirect!
+    assert_select 'div.alert', text: 'Not authorized.', count: 1
+  end
+
+  test 'transfer_submitter can not access file rename form' do
+    sign_in users(:transfer_submitter)
+    @thesis = theses(:publication_review)
+    @attachment = @thesis.files.first
+    get "/file/rename/#{@thesis.id}/#{@attachment.id}"
+    assert_redirected_to '/'
+    follow_redirect!
+    assert_select 'div.alert', text: 'Not authorized.', count: 1
+  end
+
+  test 'thesis processors can access file rename form' do
+    sign_in users(:processor)
+    @thesis = theses(:publication_review)
+    @attachment = @thesis.files.first
+    get "/file/rename/#{@thesis.id}/#{@attachment.id}"
+    assert_response :success
+  end
+
+  test 'thesis admins can access file rename form' do
+    sign_in users(:thesis_admin)
+    @thesis = theses(:publication_review)
+    @attachment = @thesis.files.first
+    get "/file/rename/#{@thesis.id}/#{@attachment.id}"
+    assert_response :success
+  end
+
+  test 'thesis admins can rename blob filename' do
+    sign_in users(:thesis_admin)
+    @thesis = theses(:publication_review)
+    @attachment = @thesis.files.first
+    assert_equal('a_pdf.pdf', @attachment.blob.filename.to_s)
+
+    post rename_file_path(@thesis, @attachment),
+         params: { attachment: { filename: 'renamed_a_pdf_too.pdf' } }
+    follow_redirect!
+    assert_equal thesis_process_path(theses(:publication_review)), path
+
+    assert_select '.alert-banner.success',
+                  text: 'MyReadyThesis file renamed_a_pdf_too.pdf been updated.', count: 1
+
+    @attachment.reload
+
+    assert_equal('renamed_a_pdf_too.pdf', @attachment.blob.filename.to_s)
+  end
+
+  test 'thesis processor can rename blob filename' do
+    sign_in users(:processor)
+    @thesis = theses(:publication_review)
+    @attachment = @thesis.files.first
+    assert_equal('a_pdf.pdf', @attachment.blob.filename.to_s)
+
+    post rename_file_path(@thesis, @attachment),
+         params: { attachment: { filename: 'renamed_a_pdf_too.pdf' } }
+    follow_redirect!
+    assert_equal thesis_process_path(theses(:publication_review)), path
+
+    assert_select '.alert-banner.success',
+                  text: 'MyReadyThesis file renamed_a_pdf_too.pdf been updated.', count: 1
+
+    @attachment.reload
+
+    assert_equal('renamed_a_pdf_too.pdf', @attachment.blob.filename.to_s)
+  end
+
+  test 'basic user can not rename blob filename' do
+    sign_in users(:basic)
+    @thesis = theses(:publication_review)
+    @attachment = @thesis.files.first
+    assert_equal('a_pdf.pdf', @attachment.blob.filename.to_s)
+
+    post rename_file_path(@thesis, @attachment),
+         params: { attachment: { filename: 'renamed_a_pdf_too.pdf' } }
+    follow_redirect!
+    assert_equal root_path, path
+
+    assert_select 'div.alert', text: 'Not authorized.', count: 1
+
+    @attachment.reload
+
+    assert_equal('a_pdf.pdf', @attachment.blob.filename.to_s)
+  end
+
+  test 'transfer_submitter user can not rename blob filename' do
+    sign_in users(:transfer_submitter)
+    @thesis = theses(:publication_review)
+    @attachment = @thesis.files.first
+    assert_equal('a_pdf.pdf', @attachment.blob.filename.to_s)
+
+    post rename_file_path(@thesis, @attachment),
+         params: { attachment: { filename: 'renamed_a_pdf_too.pdf' } }
+    follow_redirect!
+    assert_equal root_path, path
+
+    assert_select 'div.alert', text: 'Not authorized.', count: 1
+
+    @attachment.reload
+
+    assert_equal('a_pdf.pdf', @attachment.blob.filename.to_s)
+  end
+
+  test 'anonymous user can not rename blob filename' do
+    @thesis = theses(:publication_review)
+    @attachment = @thesis.files.first
+    assert_equal('a_pdf.pdf', @attachment.blob.filename.to_s)
+
+    post rename_file_path(@thesis, @attachment),
+         params: { attachment: { filename: 'renamed_a_pdf_too.pdf' } }
+    assert_redirected_to '/login'
+
+    @attachment.reload
+
+    assert_equal('a_pdf.pdf', @attachment.blob.filename.to_s)
+  end
+
+  test 'renaming a file does not change the file checksum' do
+    sign_in users(:thesis_admin)
+    @thesis = theses(:publication_review)
+    @attachment = @thesis.files.first
+    assert_equal('a_pdf.pdf', @attachment.blob.filename.to_s)
+    assert_equal('KADsjJnGD1sVUgvqyZOaRg==', @attachment.checksum)
+
+    post rename_file_path(@thesis, @attachment),
+         params: { attachment: { filename: 'renamed_a_pdf_too.pdf' } }
+    follow_redirect!
+    assert_equal thesis_process_path(theses(:publication_review)), path
+
+    assert_select '.alert-banner.success',
+                  text: 'MyReadyThesis file renamed_a_pdf_too.pdf been updated.', count: 1
+
+    @attachment.reload
+
+    assert_equal('renamed_a_pdf_too.pdf', @attachment.blob.filename.to_s)
+    assert_equal('KADsjJnGD1sVUgvqyZOaRg==', @attachment.checksum)
+  end
+end