Fix the rake task and importer instead

lib/email/receiver.rb

@@ -890,12 +890,12 @@ module Email
 
     def create_post_with_attachments(options = {})
       # deal with attachments
-      options[:raw] = add_attachments(options[:raw], options[:user].id, options)
+      options[:raw] = add_attachments(options[:raw], options[:user], options)
 
       create_post(options)
     end
 
-    def add_attachments(raw, user_id, options = {})
+    def add_attachments(raw, user, options = {})
       rejected_attachments = []
       attachments.each do |attachment|
         tmp = Tempfile.new(["discourse-email-attachment", File.extname(attachment.filename)])
@@ -904,7 +904,7 @@ module Email
           File.open(tmp.path, "w+b") { |f| f.write attachment.body.decoded }
           # create the upload for the user
           opts = { for_group_message: options[:is_group_message] }
-          upload = UploadCreator.new(tmp, attachment.filename, opts).create_for(user_id)
+          upload = UploadCreator.new(tmp, attachment.filename, opts).create_for(user.id)
           if upload&.valid?
             # try to inline images
             if attachment.content_type&.start_with?("image/")

lib/tasks/posts.rake

@@ -277,7 +277,7 @@ task 'posts:refresh_emails', [:topic_id] => [:environment] do |_, args|
       receiver = Email::Receiver.new(post.raw_email)
 
       body, elided = receiver.select_body
-      body = receiver.add_attachments(body || '', post.user_id)
+      body = receiver.add_attachments(body || '', post.user)
       body << Email::Receiver.elided_html(elided) if elided.present?
 
       post.revise(Discourse.system_user, { raw: body, cook_method: Post.cook_methods[:regular] },

script/import_scripts/mbox/importer.rb

@@ -131,7 +131,8 @@ module ImportScripts::Mbox
 
       if row['attachment_count'].positive?
         receiver = Email::Receiver.new(row['raw_message'])
-        body = receiver.add_attachments(body, user_id)
+        user = User.find(user_id)
+        body = receiver.add_attachments(body, user)
       end
 
       body << Email::Receiver.elided_html(elided) if elided.present?