Sinatra set cache_control to static files in public folder compile error

Question

I'm not sure why but when I set this setting it can't compile

set :static_cache_control, [:public, :max_age => 300]

This is what I get

syntax error, unexpected tASSOC, expecting ']' (SyntaxError)
  set :static_cache_control, [:public, :max_age => 300]
                                                  ^

I just want to set "expires" header to css, javaascript and image files.

Thanks.

Answer 1

I'm guessing you're using Ruby 1.8.7. It seems that the syntax shown in the Sinatra docs, where the last entry in an array is converted to a hash, was introduced in Ruby 1.9 and isn't in 1.8.7.

Try explicitly wrapping the hash entries with braces {}:

set :static_cache_control, [:public, {:max_age => 300}]

(Or upgrade Ruby.)