Adds a rake task for refreshing posts received via email

This is useful when the email_reply_trimmer gem was updated and you want to apply those changes to existing posts.

lib/tasks/posts.rake

@@ -238,3 +238,27 @@ task 'posts:defer_all_flags' => :environment do
 
   puts "", "#{flags_deferred} flags deferred!", ""
 end
+
+desc 'Refreshes each post that was received via email'
+task 'posts:refresh_emails', [:topic_id] => [:environment] do |_, args|
+  posts = Post.where.not(raw_email: nil).where(via_email: true)
+  posts = posts.where(topic_id: args[:topic_id]) if args[:topic_id]
+
+  updated = 0
+  total = posts.count
+
+  posts.find_each do |post|
+    receiver = Email::Receiver.new(post.raw_email)
+
+    body, elided = receiver.select_body
+    body = receiver.add_attachments(body || '', post.user_id)
+    body << Email::Receiver.elided_html(elided) if elided.present?
+
+    post.revise(Discourse.system_user, { raw: body }, skip_revision: true, skip_validations: true)
+    updated += 1
+
+    print_status(updated, total)
+  end
+
+  puts "", "Done. #{updated} posts updated.", ""
+end