Fixing invalid UTF-8 characters

fix_encoding.rb

# first method
def enforce_utf8(from = nil)
  begin
    self.is_utf8? ? self : Iconv.iconv('utf8', from, self).first
  rescue
    converter = Iconv.new('UTF-8//IGNORE//TRANSLIT', 'ASCII//IGNORE//TRANSLIT') 
    converter.iconv(self).unpack('U*').select{ |cp| cp < 127 }.pack('U*')
  end
end

# second method
ic = Iconv.new('UTF-8//IGNORE', 'UTF-8')
valid_string = ic.iconv(untrusted_string + ' ')[0..-2]