Erubis not working when executed from PHP

Question

I'm calling a Ruby script from PHP with system('ruby show.rb filename').

The show.rb looks like this:

require 'erubis'
f = ARGV[0]
puts f
input = File.read(f)
eruby = Erubis::Eruby.new(input)
puts eruby.result(binding())

When executing the command ruby show.rb filename in the console everything is printed out, but when calling it from PHP it's only printing the filename, but the template is not rendered. To see errors I piped stderr -> stdout in the PHP call and I got this

/Library/Ruby/Gems/2.3.0/gems/erubis-2.7.0/lib/erubis/converter.rb:132:in 'scan': invalid byte sequence in US-ASCII (ArgumentError) from /Library/Ruby/Gems/2.3.0/gems/erubis-2.7.0/lib/erubis/converter.rb:132:in 'convert_input' from /Library/Ruby/Gems/2.3.0/gems/erubis-2.7.0/lib/erubis/converter.rb:36:in 'convert' from /Library/Ruby/Gems/2.3.0/gems/erubis-2.7.0/lib/erubis/engine.rb:30:in 'initialize' from show.rb:5:in 'new' from show.rb:5:in temp/Newsletter.rb'

I'm new to Ruby. Are there maybe any option parameters to fix this? What is PHP doing differently there, that the error can occur?

Answer 1

I don't know why, but when opening a erubis template file inside show.rb called by PHP it must be opened as a binary file. So I only had to change show.rb to:

require 'erubis'
f = ARGV[0]
handle = File.open(f, "rb") # "rb" fixed the issue.
input = handle.read()
handle.close()
eruby = Erubis::Eruby.new(input)
puts eruby.result(binding())