cherrypy_dynpool.py

"""
>>> mon = ThreadPoolMonitor(cherrypy.engine)
>>> mon.run()
"""

import cherrypy
from cherrypy.process.plugins import Monitor
from dynpool import DynamicPoolResizer

try:
    from cherrypy.wsgiserver import ThreadPool
except ImportError:
    from cheroot.workers.threadpool import ThreadPool


def get_pool_resizer(self, minspare=1, maxspare=5, shrinkfreq=10, logfreq=0,
                     logger=None):
    return DynamicPoolResizer(
        self, minspare, maxspare, shrinkfreq, logfreq, logger)


ThreadPool.size = property(lambda self: len(self._threads))
ThreadPool.get_pool_resizer = get_pool_resizer


class ThreadPoolMonitor(Monitor):

    MINSPARE = 5
    MAXSPARE = 15
    SHRINKFREQ = 5
    LOGFREQ = 0

    def __init__(self, bus):
        self._run = lambda: None
        super(ThreadPoolMonitor, self).__init__(bus, self.run, frequency=1)

    def run(self):
        self._run()

    def configure(self, thread_pool, logger=None):
        minspare = cherrypy.config.get(
            'server.thread_pool_minspare', self.MINSPARE)
        maxspare = cherrypy.config.get(
            'server.thread_pool_maxspare', self.MAXSPARE)
        shrinkfreq = cherrypy.config.get(
            'server.thread_pool_shrink_frequency', self.SHRINKFREQ)
        logfreq = cherrypy.config.get(
            'server.thread_pool_log_frequency', self.LOGFREQ)
        resizer = thread_pool.get_pool_resizer(
            minspare=minspare,
            maxspare=maxspare,
            shrinkfreq=shrinkfreq,
            logfreq=logfreq,
            logger=logger or (lambda: None)
        )
        self._run = resizer.run

    def stop(self):
        self._run = lambda: None
        super(ThreadPoolMonitor, self).stop()
    stop.priority = 10