feedmixer_wsgi.py

"""
This module instantiates the feedmixer WSGI object with sensible defaults and a
rotating logfile (or to syslog if running multiprocess) as both `api` and
`application` (default names used by common WSGI servers). To start the service
with gunicorn_, for example, clone the repository and in the root directory
run::

$ gunicorn feedmixer_wsgi

This file can be used-as is or copied as a template (to customize things like
the title, description, logging, etc.)

The top-level install directory must be writable by the server running the app,
because it creates the logfiles ('fm.log' and 'fm.log.1') there.

.. _gunicorn: http://gunicorn.org/
"""
from feedmixer_api import wsgi_app
import socket
import requests
import cachecontrol
import logging
import logging.handlers
import multiprocessing
import os


LOG_PATH = 'fm.log'
LOG_LEVEL = logging.INFO
#LOG_LEVEL = logging.DEBUG
TIMEOUT = 120  # time to wait for http requests (seconds)
socket.setdefaulttimeout(TIMEOUT)

# all requests share a requests.session object so they can share a CacheControl cache
SESS = cachecontrol.CacheControl(requests.session())

def application(environ, start_response):
    """
    Wrap the main WSGI app so that we can intercept the 'wsgi.multiprocess'
    environment variable to set up logging accordingly.
    """
    pid = multiprocessing.current_process().pid

    is_multiprocess = environ.get('wsgi.multiprocess', False)
    if is_multiprocess:
        # log to the syslog daemon
        handler = logging.handlers.SysLogHandler(address='/dev/log')
    else:
        # Setup root logger to log to rotating log file
        handler = logging.handlers.RotatingFileHandler(LOG_PATH, maxBytes=100000,
					               backupCount=1)
    format_str = "fm-%(name)s-" + "%d" % pid +": "
    format_str += "%(asctime)s %(levelname)s:%(message)s"
    formatter = logging.Formatter(format_str)
    handler.setFormatter(formatter)
    handler.setLevel(LOG_LEVEL)
    root_logger = logging.getLogger()
    root_logger.setLevel(LOG_LEVEL)
    root_logger.handlers = []
    root_logger.addHandler(handler)

    # setup and return actual app:
    api = wsgi_app(sess=SESS)
    return api(environ, start_response)

api = application