upload submissions to submissions folder if feature is enabled

test plan:
 - enable the submissions folder feature
 - create an assignment that accepts file submissions
 - submit the assignment by uploading a file
 - ensure it is uploaded to the read-only Submissions folder
 - repeat this test with a group assignment

 (NOTE: submitting an assignment by choosing an alredy-uploaded
        file will not yet copy the file into the Submissions
        folder; this is coming up in another commit)

closes CNVS-28138

Change-Id: I836b26324cfa87d9a3ea62ca80569bcdfbb3b671
Reviewed-on: https://gerrit.instructure.com/77922
Tested-by: Jenkins
Reviewed-by: James Williams  <jamesw@instructure.com>
QA-Review: Jahnavi Yetukuri <jyetukuri@instructure.com>
Product-Review: Jeremy Stanley <jeremy@instructure.com>

app/controllers/files_controller.rb

@@ -750,6 +750,10 @@ class FilesController < ApplicationController
           @folder = @context.folders.active.where(id: params[:attachment][:folder_id]).first
           return unless authorized_action(@folder, @current_user, :manage_contents)
         end
+        if intent == 'submit' && context.respond_to?(:submissions_folder) &&
+            @asset && @asset.context.root_account.feature_enabled?(:submissions_folder)
+          @folder ||= @context.submissions_folder(@asset.context)
+        end
         @folder ||= Folder.unfiled_folder(@context)
         @attachment.folder_id = @folder.id
       end

app/controllers/submissions_api_controller.rb

@@ -457,7 +457,7 @@ class SubmissionsApiController < ApplicationController
     permission = :nothing if @user != @current_user
     # we don't check quota when uploading a file for assignment submission
     if authorized_action(@assignment, @current_user, permission)
-      api_attachment_preflight(@user, request, :check_quota => false)
+      api_attachment_preflight(@user, request, :check_quota => false, :submission_context => @context)
     end
   end
 

app/models/group.rb

@@ -733,7 +733,7 @@ class Group < ActiveRecord::Base
     user.favorites.where(:context_type => 'Group', :context_id => self).exists?
   end
 
-  def submissions_folder
+  def submissions_folder(_course = nil)
     return @submissions_folder if @submissions_folder
     Folder.unique_constraint_retry do
       @submissions_folder = self.folders.where(parent_folder_id: Folder.root_folders(self).first, submission_context_code: 'root')

lib/api/v1/attachment.rb

@@ -151,6 +151,8 @@ module Api::V1::Attachment
     end
     if @attachment.folder
       return unless authorized_action(@attachment.folder, @current_user, :manage_contents)
+    elsif opts[:submission_context] && opts[:submission_context].root_account.feature_enabled?(:submissions_folder)
+      @attachment.folder = context.submissions_folder(opts[:submission_context]) if context.respond_to?(:submissions_folder)
     end
     duplicate_handling = check_duplicate_handling_option(params)
     if opts[:check_quota]

spec/apis/v1/submissions_api_spec.rb

@@ -2863,6 +2863,18 @@ describe 'Submissions API', type: :request do
         json = api_call(:post, "/api/v1/courses/#{@course.id}/assignments/#{@assignment.id}/submissions/#{@student2.id}/files",
                         { :controller => "submissions_api", :action => "create_file", :format => "json", :course_id => @course.to_param, :assignment_id => @assignment.to_param, :user_id => @student2.to_param }, {}, {}, { :expected_status => 401 })
       end
+
+      it "should upload to a student's Submissions folder if the feature is enabled" do
+        @course.root_account.enable_feature! :submissions_folder
+        preflight(name: 'test.txt', size: 12345, content_type: 'text/plain')
+        f = Attachment.last.folder
+        expect(f.submission_context_code).to eq @course.asset_string
+      end
+
+      it "should not do so otherwise" do
+        preflight(name: 'test.txt', size: 12345, content_type: 'text/plain')
+        expect(Attachment.last.folder).not_to be_for_submissions
+      end
     end
 
     it "should reject invalid urls" do

spec/controllers/files_controller_spec.rb

@@ -920,6 +920,40 @@ describe FilesController do
       expect(response.status).to eq 401
     end
 
+    it "creates a file in the submissions folder if intent=='submit' and the feature is enabled" do
+      @course.root_account.enable_feature! :submissions_folder
+      user_session(@student)
+      assignment = @course.assignments.create!(:submission_types => 'online_upload')
+      post 'create_pending', {:attachment => {
+        :context_code => assignment.context_code,
+        :asset_string => assignment.asset_string,
+        :filename => 'test.txt',
+        :intent => 'submit'
+      }}
+      f = assigns[:attachment].folder
+      expect(f.submission_context_code).to eq @course.asset_string
+    end
+
+    it "uses a submissions folder for group assignments when the feature is enabled" do
+      @course.root_account.enable_feature! :submissions_folder
+      user_session(@student)
+      category = group_category
+      assignment = @course.assignments.create(:group_category => category, :submission_types => 'online_upload')
+      group = category.groups.create(:context => @course)
+      group.add_user(@student)
+      user_session(@student)
+      post 'create_pending', {:attachment => {
+        :context_code => @course.asset_string,
+        :asset_string => assignment.asset_string,
+        :intent => 'submit',
+        :filename => "bob.txt"
+      }}
+      expect(response).to be_success
+      expect(assigns[:attachment]).not_to be_nil
+      expect(assigns[:attachment].context).to eq group
+      expect(assigns[:attachment].folder).to be_for_submissions
+    end
+
     context "sharding" do
       specs_require_sharding