tornado_server.py

#!/usr/bin/env python
'''
    This is an example http server application

    Run this application with python, then you can open your browser to
    http://localhost:8888/ to view the index.html page.
'''

from os.path import abspath, dirname, exists, join
from optparse import OptionParser

import tornado.web

from tornado.ioloop import IOLoop

import logging
logger = logging.getLogger('dashboard')

log_datefmt = "%H:%M:%S"
log_format = "%(asctime)s:%(msecs)03d %(levelname)-8s: %(name)-20s: %(message)s"

class NonCachingStaticFileHandler(tornado.web.StaticFileHandler):
    '''
        This static file handler disables caching, to allow for easy
        development of your Dashboard
    '''

    # This is broken in tornado, disable it
    def check_etag_header(self):
        return False
    
    def set_extra_headers(self, path):
        # Disable caching
        self.set_header('Cache-Control', 'no-store, no-cache, must-revalidate, max-age=0')

if __name__ == '__main__':

    # Setup options here
    parser = OptionParser()

    parser.add_option('-p', '--port', default=8888,
                      help='Port to run web server on')

    parser.add_option('-v', '--verbose', default=False, action='store_true',
                      help='Enable verbose logging')

    options, args = parser.parse_args()

    # Setup logging
    logging.basicConfig(datefmt=log_datefmt,
                        format=log_format,
                        level=logging.DEBUG if options.verbose else logging.INFO)

    # setup tornado application with static handler + networktables support
    www_dir = abspath(join(dirname(__file__), 'www'))
    index_html = join(www_dir, 'index.html')

    if not exists(www_dir):
        logger.error("Directory '%s' does not exist!" % www_dir)
        exit(1)

    if not exists(index_html):
        logger.warn("%s not found" % index_html)

    app = tornado.web.Application(
        [
            (r"/()", NonCachingStaticFileHandler, {"path": index_html}),
            (r"/(.*)", NonCachingStaticFileHandler, {"path": www_dir})
        ]
    )

    # Start the app
    logger.info("Listening on http://localhost:%s/" % options.port)

    app.listen(options.port)
    IOLoop.current().start()