Heroku: Error encountered while saving cache

Question

Everything works fine locally, but when pushing to Heroku:

   Warning. Error encountered while saving cache /tmp/build_1b5c442a-d24e-4f80-9755-a0bd15d7f029/t         


        

Answer 1

First you might want to update

bundle update sass-rails
bundle update sass

Then the more critical part (make sure you uninstall the sass version in your Gemfile.lock)

gem uninstall sass
bundle install

Answer 2

This is related to the recent upgrade of the sass gem to 3.3.0. The sass gem is a dependency of a couple of other sass gems, so even if you don't have it in your Gemfile, it is probably getting loaded. Do a "bundle show" locally and on Heroku and I'm fairly sure you'll see they are different versions (sass was upgraded to 3.3.0 just a couple days ago).

Add:

gem 'sass', '3.2.13'

to your Gemfile and that should fix things for you. Then go submit an issue on github for this gem.

Hope this helps, it worked for me!

Answer 3

This is a known bug in Sass 3.3.0, the Sprockets importer is unserialized and so un-cacheable causing this error. For the bug report see this. Without the caching, Sass compiles excruciatingly slow which leads to the timeout on heroku servers.