Wrapper around Closure Compiler API

get_closure.py

import httplib
import sys
import urllib
from contextlib import closing

################################################################################################################

# Compilation level
WHITESPACE_ONLY_CL        = 'WHITESPACE_ONLY'
SIMPLE_OPTIMIZATIONS_CL   = 'SIMPLE_OPTIMIZATIONS'
ADVANCED_OPTIMIZATIONS_CL = 'ADVANCED_OPTIMIZATIONS'

# Output format
TEXT_OF = 'text'
XML_OF  = 'xml'
JSON_OF = 'json'

# Output information
COMPILED_CODE_OI = 'compiled_code'
WARNINGS_OI      = 'warnings'
ERRORS_OI        = 'errors'
STATISTICS_OI    = 'statistics'

# Warning level
QUIET_WL   = 'QUIET'
DEFAULT_WL = 'DEFAULT_WL'
VERBOSE_WL = 'VERBOSE_WL'

# Language
ECMASCRIPT3_LANG        = 'ECMASCRIPT3'
ECMASCRIPT5_LANG        = 'ECMASCRIPT5'
ECMASCRIPT5_STRICT_LANG = 'ECMASCRIPT5_STRICT'

################################################################################################################

class ClosureCompiler:

    def call_closure_api(self, js_urls, pretty_print=False, print_input_delimiter=False, **kwargs):
        # There are some arguments which can not be put into the kwargs dict, since the keys are repeated:
        #  - code_url
        #  - formatting
        # So I must build an args list from kwargs so that I can add the extra POST parameters before calling urlendcode
        args = list(kwargs.items())
        if js_urls :
            for js_url in js_urls :
                args.append(('code_url', js_url))
        if pretty_print : args.append(('formatting', 'pretty_print'))
        if print_input_delimiter : args.append(('formatting', 'print_input_delimiter'))
        with closing(httplib.HTTPConnection('closure-compiler.appspot.com')) as conn:
            conn.request(
                'POST', '/compile',
                urllib.urlencode(args),
                headers={"Content-type": "application/x-www-form-urlencoded"}
            )
            return conn.getresponse().read()

    def get_js(self, js_urls=None, js_code=None, output_file_name=None, pretty_print=False, print_input_delimiter=False, use_closure_library=True,
               output_format=TEXT_OF, compilation_level=WHITESPACE_ONLY_CL, warning_level=DEFAULT_WL, output_info=COMPILED_CODE_OI,
               language=ECMASCRIPT3_LANG):
        kwargs = dict(
            compilation_level=compilation_level,
            output_format=output_format,
            output_info=output_info,
            use_closure_library=use_closure_library,
            language=language,
        )
        if js_code : kwargs['js_code'] = js_code
        if output_file_name : kwargs['output_file_name'] = output_file_name
        return self.call_closure_api(js_urls, pretty_print, print_input_delimiter, **kwargs)

################################################################################################################

closcomp = ClosureCompiler()

output_file_name = 'libphonenumber.js'
output_file_name = None
js_urls = [
    'http://libphonenumber.googlecode.com/svn/trunk/javascript/i18n/phonenumbers/phonemetadata.pb.js',
    'http://libphonenumber.googlecode.com/svn/trunk/javascript/i18n/phonenumbers/phonenumber.pb.js',
    'http://libphonenumber.googlecode.com/svn/trunk/javascript/i18n/phonenumbers/metadata.js',
    'http://libphonenumber.googlecode.com/svn/trunk/javascript/i18n/phonenumbers/phonenumberutil.js',
    'http://libphonenumber.googlecode.com/svn/trunk/javascript/i18n/phonenumbers/asyoutypeformatter.js',
]
#js_urls = None
#js_code = 'alert("hi");'
js_code = None

print closcomp.get_js(js_urls, js_code, output_file_name, compilation_level=ADVANCED_OPTIMIZATIONS_CL)

################################################################################################################