Metadata-Version: 2.0
Name: polymer
Version: 0.0.30
Summary: Polymer
Home-page: http://github.com/mpenning/polymer
Author: David Michael Pennington
Author-email: mike@pennington.net
License: GPL
Platform: any
Classifier: Development Status :: 4 - Beta
Classifier: Environment :: Plugins
Classifier: Intended Audience :: Developers
Classifier: Intended Audience :: System Administrators
Classifier: Intended Audience :: Information Technology
Classifier: License :: OSI Approved :: GNU General Public License (GPL)
Classifier: Natural Language :: English
Classifier: Operating System :: OS Independent
Classifier: Programming Language :: Python
Classifier: Topic :: Software Development :: Libraries :: Python Modules
Requires-Dist: colorama

Summary
-------

A simple framework to run tasks in parallel.  It's similar to 
multiprocessing.Pool, but has a few enhancements over that.  For example,
mp.Pool is only useful for multiprocessing functions (not objects).  You can
wrap a function around the object, but it's nicer just to deal with task
objects themselves.

Polymer is mostly useful for its Worker error logging and run-time statistics.
It also restarts crashed multiprocessing workers automatically (not true with
multiprocessing.Pool).  When a worker crashes, Polymer knows what the worker 
was doing and resubmits that task as well.  This definitely is not fool-proof;
however, it's a helpful feature.

Once TaskMgr().supervise() finishes, a list of object instances is returned. 
You can store per-task results as an attribute of each object instance.

Usage
-----

.. code:: python

   import time

   from polymer.Polymer import ControllerQueue, TaskMgr
   from polymer.abc_task import BaseTask

   class SimpleTask(BaseTask):
      def __init__(self, text="", wait=0.0):
          super(SimpleTask, self).__init__()
          self.text = text
          self.wait = wait

      def run(self):
          """run() is where all the work is done; this is called by TaskMgr()"""
          ## WARNING... using try / except in run() could squash Polymer's
          ##      internal error logging...
          time.sleep(float(self.wait/10))
          print self.text

      def __eq__(self, other):
          """Define how tasks are uniquely identified"""
          if other.text==self.text:
              return True
          return False

      def __repr__(self):
          return """<{0}, wait: {1}>""".format(self.text, self.wait)

   def Controller():
       """Controller() builds a list of tasks, and queues them to the TaskMgr
       There is nothing special about the name Controller()... it's just some
       code to build a list of SimpleTask() instances."""

       tasks = list()

       ## Build ten tasks... do *not* depend on execution order...
       num_tasks = 10
       for ii in range(0, num_tasks):
           tasks.append(SimpleTask(text="Task {0}".format(ii), wait=ii))

       targs = {
           'work_todo': tasks,  # a list of SimpleTask() instances
           'hot_loop': False,   # If True, continuously loop over the tasks
           'worker_count': 3,           # Number of workers (default: 5)
           'resubmit_on_error': False,  # Do not retry errored jobs...
           'queue': ControllerQueue(),
           'worker_cycle_sleep': 0.001, # Worker sleep time after a task
           'log_stdout': False,         # Don't log to stdout (default: True)
           'log_path':  "taskmgr.log",  # Log file name
           'log_level': 0,              # Logging off is 0 (debugging=3)
           'log_interval': 10,          # Statistics logging interval
       }

       ## task_mgr reads and executes the queued tasks
       task_mgr = TaskMgr(**targs)

       ## a set() of completed task objects are returned after supervise()
       results = task_mgr.supervise()
       return results

   if __name__=='__main__':
       Controller()

License
-------

GPLv3


