Add file name validation to create new Office file modal window

app/controllers/assets_controller.rb

@@ -191,11 +191,25 @@ class AssetsController < ApplicationController
     render_403 && return unless %w(docx xlsx pptx).include?(params[:file_type])
 
     # Asset validation
+    original_filename = "#{params[:file_name]}.#{params[:file_type]}"
     file = Paperclip.io_adapters.for(StringIO.new)
-    file.original_filename = "#{params[:file_name]}.#{params[:file_type]}"
+    file.original_filename = original_filename
     file.content_type = wopi_content_type(params[:file_type])
     asset = Asset.new(file: file, created_by: current_user, file_present: true)
 
+    # Filename length validation (this cannot be checked by Paperclip,
+    # as it depends on OS)
+    if original_filename.length > Constants::FILENAME_MAX_LENGTH
+      render json: {
+        message: {
+          file: I18n.t(
+            'assets.create_wopi_file.errors.file_name_too_long',
+            limit: Constants::FILENAME_MAX_LENGTH
+          )
+        }
+      }, status: 400 and return
+    end
+
     unless asset.valid?(:wopi_file_creation)
       render json: {
         message: asset.errors

config/initializers/constants.rb

@@ -23,6 +23,9 @@ class Constants
   COLOR_MAX_LENGTH = 7
   # Max characters for text in dropdown list element
   DROPDOWN_TEXT_MAX_LENGTH = 15
+  # Max characters limit for (on most operating systems, it's ~255 characters,
+  # but this is with a bit more safety margin)
+  FILENAME_MAX_LENGTH = 100
   # Max characters for filenames, after which they get truncated
   FILENAME_TRUNCATION_LENGTH = 50
   # Max characters for names of exported files and folders, after which they get

config/locales/en.yml

@@ -1915,6 +1915,7 @@ en:
       errors:
         forbidden: 'You do not have permission to add files.'
         not_found: 'Element not found.'
+        file_name_too_long: 'is too long (maximum is %{limit} characters, with extension)'
   atwho:
     no_results: "No results found"
     users: