ipc
===========================================================

.. module:: smisk.ipc
.. versionadded:: 1.1.2

Inter-process communication


Functions
-------------------------------------------------


.. function:: shared_dict(persistent=False) -> dict

  Aquire the shared dictionary which can be concurrently manipulated by multiple processes.
  
  This is a convenience function which aquires a dict type which is shared between all processes running the same __main__ program. By default, this is simply (a imported reference to) the :func:`~smisk.ipc.bsddb.shared_dict()` function, returning a hashed DBDict stored in shared memory.
  
  There are other implementations available, which all provide the same interface, making future backend swap a simple drop-in operation.
  
  Example of use in Smisk applications::
    
    from smisk.core import Application, main
    from smisk.ipc import shared_dict
    
    class App(Application):
      def application_will_start(self):
        self.sd = shared_dict()
      
      def service(self):
        # Do something useful with self.sd
        try:
          response = self.sd[request.url.path]
        except KeyError:
          # Build response...
          import os
          response = 'Hello! This was built by process #%d' % os.getpid()
          self.sd[request.url.path] = response
        self.response(response)
    
    main(App)
  
  :param persistent:
    If True, the dictionary will persist between application restarts (i.e.
    the contents of the dict is synced and keept on disk).


Modules
-------------------------------------------------

.. toctree::
  :maxdepth: 1
  
  smisk.ipc.bsddb
  smisk.ipc.memcached