JavaScript Minifier

# JS Minify
# Python script that can process all JavaScript files in a directory
# through the YUI Compressor
 

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="/path/to/yuicompressor-2.4.1.jar", 
    )
 
    parser.add_option("--dir", dest="dir", help="Directory to look for JavaScript files")
    parser.add_option("--compressor", dest="compressor", help="Path to the YUI Compressor 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 YUI Compressor, save the output as .min.js
        os.system("java -jar %(compressor)s %(input)s -o %(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()