chef-solo-automator's cookbook tarball generation could be more robust. The following error caused a bootstrap to copy no cookbooks to the host, yet still succeed. (the root cause in this case was me messing with cookbooks while a provision was in-flight, but this still should have at least failed the bootstrap task).
2017-01-04 01:09:27 +0000 coopr.novalocal.52042 DEBUG: Generating cookbooks.tar.gz from cookbooks
tar: cookbooks/coopr_packages/recipes/.default.rb.swp: Cannot open: Permission denied
tar: Exiting with failure status due to previous errors
2017-01-04 01:09:27 +0000 coopr.novalocal.52042 DEBUG: Generation complete: cookbooks.tar.gz