/var/log/glance is only defined at ./cookbooks/glance/attributes/default.rb. So it seems no need any replace for it.
/var/cache/glance is hardcoded at ./templates/default/glance-api.conf.erb as signing_dir = /var/cache/glance/keystone-signing

<%= %> includes just the variable itself so i can define a variable for it. But not sure whether it is necessary.