minify js with closure compiler

jsminify.py

#!/usr/bin/env python


# JS Minify
# Python script that can process all JavaScript files in a directory
# through the Closure compiler
# original: http://taylanpince.com/blog/posts/automated-javascript-minification-with-fabric/ 

import os
from optparse import OptionParser
 

def main():
    # Setup the option parser
    parser = OptionParser(
        usage="Usage: %prog [options] --dir=SOURCE_DIR", 
        version="%prog 0.1"
    )
    
    parser.set_defaults(
        compressor="/home/chris/share/compiler-latest/compiler.jar", 
    )
    
    parser.add_option("--dir", dest="dir",
                      help="Directory to look for JavaScript files")
    parser.add_option("--compressor", dest="compressor",
                      help="Path to the Closure compiler jar file")
    
    (options, args) = parser.parse_args()
    
    if not options.dir:
        parser.error("You have to specify a directory.")
    
    # Loop through all files with .js extension
    for file in [x for x in os.listdir(options.dir)
                 if os.path.splitext(x)[1].lower() == ".js"]:
        print "Compressing %s" % file
        
        # Setup the input/output paths
        input = os.path.join(options.dir, file)
        output = os.path.join(options.dir, os.path.splitext(file)[0] + ".min.js")
        
        # Pass the file through the Compressor, save the output as .min.js
        os.system("java -jar %(compressor)s "
                  "--js %(input)s --js_output_file %(output)s" % {
            "compressor": options.compressor,
            "input": input,
            "output": output,
        })
        
        # Replace the original file with the minified version
        os.rename(output, input)
 

if __name__ == "__main__":
    main()