Reduce SQL queries for querying files when creating submissions

This is especially useful for the RemoteEvaluationsController.

Closes CODEOCEAN-KX

app/controllers/concerns/file_parameters.rb

@@ -5,7 +5,8 @@ module FileParameters
     if exercise && params
       # We only want to load the files once, to avoid multiple database queries.
       # Further, we use `unscope` to avoid that the `order` scope is applied
-      files = CodeOcean::File.unscope(:order).where(id: params.values.pluck(:file_id))
+      # Optimization: We query for the `file_type` here, which is used in `CodeOcean::File#set_ancestor_values`.
+      files = CodeOcean::File.unscope(:order).where(id: params.values.pluck(:file_id)).includes(:file_type)
 
       params.reject do |_, file_attributes|
         # This mechanism seems cumbersome, but we cannot use an index here.
@@ -19,6 +20,10 @@ module FileParameters
         next true if file.context_type == 'Submission' && (file.context.user_id != current_user.id || file.context.user_type != current_user.class.name)
         next true if file.context_type == 'CommunitySolution' && controller_name != 'community_solutions'
 
+        # Optimization: We already queried the ancestor file, let's reuse the object.
+        file_attributes[:file] = file
+        file_attributes.delete(:file_id)
+
         false
       end
     else

app/controllers/remote_evaluation_controller.rb

@@ -86,11 +86,10 @@ class RemoteEvaluationController < ApplicationController
 
     files_attributes = remote_evaluation_params[:files_attributes]
     submission_params = remote_evaluation_params.except(:validation_token)
-    submission_params[:exercise_id] = remote_evaluation_mapping.exercise_id
+    submission_params[:exercise] = remote_evaluation_mapping.exercise
-    submission_params[:user_id] = remote_evaluation_mapping.user_id
+    submission_params[:user] = remote_evaluation_mapping.user
     submission_params[:study_group_id] = remote_evaluation_mapping.study_group_id
     submission_params[:cause] = cause
-    submission_params[:user_type] = remote_evaluation_mapping.user_type
     submission_params[:files_attributes] =
       reject_illegal_file_attributes(remote_evaluation_mapping.exercise, files_attributes)
     submission_params

app/models/code_ocean/file.rb

@@ -131,7 +131,7 @@ module CodeOcean
     end
 
     def set_ancestor_values
-      %i[feedback_message file_type_id hidden name path read_only role weight].each do |attribute|
+      %i[feedback_message file_type hidden name path read_only role weight].each do |attribute|
         send(:"#{attribute}=", ancestor.send(attribute))
       end
     end