how can i optimize the compress process? #4

@@index = 0
@@api_keys = []
def self.tinify(file_path)
 if @@api_keys.length == 0
 UI.message("no api keys found")
 return
 end
 Tinify.key = @@api_keys[@@index]
 UI.message("current api key is: #{Tinify.key}")
 file_name = File.basename file_path
 UI.message("#{file_name} start to ready compress image")
 begin
 source = Tinify.from_file file_path
 source.to_file file_path
 UI.message("#{file_name} compress success!")
 @@index += 1
 if @@index == @@api_keys.length
 @@index = 0
 end
 rescue Tinify::AccountError => e
 @@index += 1
 if @@index == @@api_keys.length
 @@index = 0
 end
 tinify file_path
 rescue => e
 UI.message("#{file_name} compress failure!")
 @@index += 1
 if @@index == @@api_keys.length
 @@index = 0
 end
 end
 end