properly handle nothing to recv in StreamKernel.abort

IPython/parallel/engine/streamkernel.py

@@ -1,433 +1,422 b''
 #!/usr/bin/env python
 """
 Kernel adapted from kernel.py to use ZMQ Streams
 """
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2010-2011  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 # Standard library imports.
 from __future__ import print_function
 
 import sys
 import time
 
 from code import CommandCompiler
 from datetime import datetime
 from pprint import pprint
 
 # System library imports.
 import zmq
 from zmq.eventloop import ioloop, zmqstream
 
 # Local imports.
 from IPython.utils.traitlets import Instance, List, Int, Dict, Set, Unicode
 from IPython.zmq.completer import KernelCompleter
 
 from IPython.parallel.error import wrap_exception
 from IPython.parallel.factory import SessionFactory
 from IPython.parallel.util import serialize_object, unpack_apply_message
 
 def printer(*args):
     pprint(args, stream=sys.__stdout__)
 
 
 class _Passer(zmqstream.ZMQStream):
     """Empty class that implements `send()` that does nothing.
     
     Subclass ZMQStream for Session typechecking
     
     """
     def __init__(self, *args, **kwargs):
         pass
     
     def send(self, *args, **kwargs):
         pass
     send_multipart = send
     
 
 #-----------------------------------------------------------------------------
 # Main kernel class
 #-----------------------------------------------------------------------------
 
 class Kernel(SessionFactory):
 
     #---------------------------------------------------------------------------
     # Kernel interface
     #---------------------------------------------------------------------------
     
     # kwargs:
     exec_lines = List(Unicode, config=True,
         help="List of lines to execute")
 
     int_id = Int(-1)
     user_ns = Dict(config=True,  help="""Set the user's namespace of the Kernel""")
     
     control_stream = Instance(zmqstream.ZMQStream)
     task_stream = Instance(zmqstream.ZMQStream)
     iopub_stream = Instance(zmqstream.ZMQStream)
     client = Instance('IPython.parallel.Client')
     
     # internals
     shell_streams = List()
     compiler = Instance(CommandCompiler, (), {})
     completer = Instance(KernelCompleter)
     
     aborted = Set()
     shell_handlers = Dict()
     control_handlers = Dict()
     
     def _set_prefix(self):
         self.prefix = "engine.%s"%self.int_id
     
     def _connect_completer(self):
         self.completer = KernelCompleter(self.user_ns)
     
     def __init__(self, **kwargs):
         super(Kernel, self).__init__(**kwargs)
         self._set_prefix()
         self._connect_completer()
         
         self.on_trait_change(self._set_prefix, 'id')
         self.on_trait_change(self._connect_completer, 'user_ns')
         
         # Build dict of handlers for message types
         for msg_type in ['execute_request', 'complete_request', 'apply_request', 
                 'clear_request']:
             self.shell_handlers[msg_type] = getattr(self, msg_type)
         
         for msg_type in ['shutdown_request', 'abort_request']+self.shell_handlers.keys():
             self.control_handlers[msg_type] = getattr(self, msg_type)
         
         self._initial_exec_lines()
     
     def _wrap_exception(self, method=None):
         e_info = dict(engine_uuid=self.ident, engine_id=self.int_id, method=method)
         content=wrap_exception(e_info)
         return content
     
     def _initial_exec_lines(self):
         s = _Passer()
         content = dict(silent=True, user_variable=[],user_expressions=[])
         for line in self.exec_lines:
             self.log.debug("executing initialization: %s"%line)
             content.update({'code':line})
             msg = self.session.msg('execute_request', content)
             self.execute_request(s, [], msg)
         
         
     #-------------------- control handlers -----------------------------
     def abort_queues(self):
         for stream in self.shell_streams:
             if stream:
                 self.abort_queue(stream)
     
     def abort_queue(self, stream):
         while True:
-            try:
-                msg = self.session.recv(stream, zmq.NOBLOCK,content=True)
-            except zmq.ZMQError as e:
-                if e.errno == zmq.EAGAIN:
-                    break
-                else:
-                    return
-            else:
-                if msg is None:
-                    return
-                else:
-                    idents,msg = msg
+            idents,msg = self.session.recv(stream, zmq.NOBLOCK, content=True)
+            if msg is None:
+                return
                 
-                # assert self.reply_socketly_socket.rcvmore(), "Unexpected missing message part."
-                # msg = self.reply_socket.recv_json()
             self.log.info("Aborting:")
             self.log.info(str(msg))
             msg_type = msg['msg_type']
             reply_type = msg_type.split('_')[0] + '_reply'
             # reply_msg = self.session.msg(reply_type, {'status' : 'aborted'}, msg)
             # self.reply_socket.send(ident,zmq.SNDMORE)
             # self.reply_socket.send_json(reply_msg)
             reply_msg = self.session.send(stream, reply_type, 
                         content={'status' : 'aborted'}, parent=msg, ident=idents)[0]
             self.log.debug(str(reply_msg))
             # We need to wait a bit for requests to come in. This can probably
             # be set shorter for true asynchronous clients.
             time.sleep(0.05)
     
     def abort_request(self, stream, ident, parent):
         """abort a specifig msg by id"""
         msg_ids = parent['content'].get('msg_ids', None)
         if isinstance(msg_ids, basestring):
             msg_ids = [msg_ids]
         if not msg_ids:
             self.abort_queues()
         for mid in msg_ids:
             self.aborted.add(str(mid))
         
         content = dict(status='ok')
         reply_msg = self.session.send(stream, 'abort_reply', content=content, 
                 parent=parent, ident=ident)
         self.log.debug(str(reply_msg))
     
     def shutdown_request(self, stream, ident, parent):
         """kill ourself.  This should really be handled in an external process"""
         try:
             self.abort_queues()
         except:
             content = self._wrap_exception('shutdown')
         else:
             content = dict(parent['content'])
             content['status'] = 'ok'
         msg = self.session.send(stream, 'shutdown_reply',
                                 content=content, parent=parent, ident=ident)
         self.log.debug(str(msg))
         dc = ioloop.DelayedCallback(lambda : sys.exit(0), 1000, self.loop)
         dc.start()
     
     def dispatch_control(self, msg):
         idents,msg = self.session.feed_identities(msg, copy=False)
         try:
             msg = self.session.unpack_message(msg, content=True, copy=False)
         except:
             self.log.error("Invalid Message", exc_info=True)
             return
         
         header = msg['header']
         msg_id = header['msg_id']
         
         handler = self.control_handlers.get(msg['msg_type'], None)
         if handler is None:
             self.log.error("UNKNOWN CONTROL MESSAGE TYPE: %r"%msg['msg_type'])
         else:
             handler(self.control_stream, idents, msg)
     
 
     #-------------------- queue helpers ------------------------------
     
     def check_dependencies(self, dependencies):
         if not dependencies:
             return True
         if len(dependencies) == 2 and dependencies[0] in 'any all'.split():
             anyorall = dependencies[0]
             dependencies = dependencies[1]
         else:
             anyorall = 'all'
         results = self.client.get_results(dependencies,status_only=True)
         if results['status'] != 'ok':
             return False
         
         if anyorall == 'any':
             if not results['completed']:
                 return False
         else:
             if results['pending']:
                 return False
         
         return True
     
     def check_aborted(self, msg_id):
         return msg_id in self.aborted
     
     #-------------------- queue handlers -----------------------------
     
     def clear_request(self, stream, idents, parent):
         """Clear our namespace."""
         self.user_ns = {}
         msg = self.session.send(stream, 'clear_reply', ident=idents, parent=parent, 
                 content = dict(status='ok'))
         self._initial_exec_lines()
     
     def execute_request(self, stream, ident, parent):
         self.log.debug('execute request %s'%parent)
         try:
             code = parent[u'content'][u'code']
         except:
             self.log.error("Got bad msg: %s"%parent, exc_info=True)
             return
         self.session.send(self.iopub_stream, u'pyin', {u'code':code},parent=parent,
                             ident='%s.pyin'%self.prefix)
         started = datetime.now()
         try:
             comp_code = self.compiler(code, '<zmq-kernel>')
             # allow for not overriding displayhook
             if hasattr(sys.displayhook, 'set_parent'):
                 sys.displayhook.set_parent(parent)
                 sys.stdout.set_parent(parent)
                 sys.stderr.set_parent(parent)
             exec comp_code in self.user_ns, self.user_ns
         except:
             exc_content = self._wrap_exception('execute')
             # exc_msg = self.session.msg(u'pyerr', exc_content, parent)
             self.session.send(self.iopub_stream, u'pyerr', exc_content, parent=parent,
                             ident='%s.pyerr'%self.prefix)
             reply_content = exc_content
         else:
             reply_content = {'status' : 'ok'}
         
         reply_msg = self.session.send(stream, u'execute_reply', reply_content, parent=parent, 
                     ident=ident, subheader = dict(started=started))
         self.log.debug(str(reply_msg))
         if reply_msg['content']['status'] == u'error':
             self.abort_queues()
 
     def complete_request(self, stream, ident, parent):
         matches = {'matches' : self.complete(parent),
                    'status' : 'ok'}
         completion_msg = self.session.send(stream, 'complete_reply',
                                            matches, parent, ident)
         # print >> sys.__stdout__, completion_msg
 
     def complete(self, msg):
         return self.completer.complete(msg.content.line, msg.content.text)
     
     def apply_request(self, stream, ident, parent):
         # flush previous reply, so this request won't block it
         stream.flush(zmq.POLLOUT)
         
         try:
             content = parent[u'content']
             bufs = parent[u'buffers']
             msg_id = parent['header']['msg_id']
             # bound = parent['header'].get('bound', False)
         except:
             self.log.error("Got bad msg: %s"%parent, exc_info=True)
             return
         # pyin_msg = self.session.msg(u'pyin',{u'code':code}, parent=parent)
         # self.iopub_stream.send(pyin_msg)
         # self.session.send(self.iopub_stream, u'pyin', {u'code':code},parent=parent)
         sub = {'dependencies_met' : True, 'engine' : self.ident,
                 'started': datetime.now()}
         try:
             # allow for not overriding displayhook
             if hasattr(sys.displayhook, 'set_parent'):
                 sys.displayhook.set_parent(parent)
                 sys.stdout.set_parent(parent)
                 sys.stderr.set_parent(parent)
             # exec "f(*args,**kwargs)" in self.user_ns, self.user_ns
             working = self.user_ns
             # suffix = 
             prefix = "_"+str(msg_id).replace("-","")+"_"
             
             f,args,kwargs = unpack_apply_message(bufs, working, copy=False)
             # if bound:
             #     bound_ns = Namespace(working)
             #     args = [bound_ns]+list(args)
 
             fname = getattr(f, '__name__', 'f')
             
             fname = prefix+"f"
             argname = prefix+"args"
             kwargname = prefix+"kwargs"
             resultname = prefix+"result"
             
             ns = { fname : f, argname : args, kwargname : kwargs , resultname : None }
             # print ns
             working.update(ns)
             code = "%s=%s(*%s,**%s)"%(resultname, fname, argname, kwargname)
             try:
                 exec code in working,working
                 result = working.get(resultname)
             finally:
                 for key in ns.iterkeys():
                     working.pop(key)
             # if bound:
             #     working.update(bound_ns)
             
             packed_result,buf = serialize_object(result)
             result_buf = [packed_result]+buf
         except:
             exc_content = self._wrap_exception('apply')
             # exc_msg = self.session.msg(u'pyerr', exc_content, parent)
             self.session.send(self.iopub_stream, u'pyerr', exc_content, parent=parent,
                                 ident='%s.pyerr'%self.prefix)
             reply_content = exc_content
             result_buf = []
             
             if exc_content['ename'] == 'UnmetDependency':
                 sub['dependencies_met'] = False
         else:
             reply_content = {'status' : 'ok'}
         
         # put 'ok'/'error' status in header, for scheduler introspection:
         sub['status'] = reply_content['status']
         
         reply_msg = self.session.send(stream, u'apply_reply', reply_content, 
                     parent=parent, ident=ident,buffers=result_buf, subheader=sub)
         
         # flush i/o
         # should this be before reply_msg is sent, like in the single-kernel code, 
         # or should nothing get in the way of real results?
         sys.stdout.flush()
         sys.stderr.flush()
     
     def dispatch_queue(self, stream, msg):
         self.control_stream.flush()
         idents,msg = self.session.feed_identities(msg, copy=False)
         try:
             msg = self.session.unpack_message(msg, content=True, copy=False)
         except:
             self.log.error("Invalid Message", exc_info=True)
             return
             
         
         header = msg['header']
         msg_id = header['msg_id']
         if self.check_aborted(msg_id):
             self.aborted.remove(msg_id)
             # is it safe to assume a msg_id will not be resubmitted?
             reply_type = msg['msg_type'].split('_')[0] + '_reply'
             status = {'status' : 'aborted'}
             reply_msg = self.session.send(stream, reply_type, subheader=status,
                         content=status, parent=msg, ident=idents)
             return
         handler = self.shell_handlers.get(msg['msg_type'], None)
         if handler is None:
             self.log.error("UNKNOWN MESSAGE TYPE: %r"%msg['msg_type'])
         else:
             handler(stream, idents, msg)
     
     def start(self):
         #### stream mode:
         if self.control_stream:
             self.control_stream.on_recv(self.dispatch_control, copy=False)
             self.control_stream.on_err(printer)
         
         def make_dispatcher(stream):
             def dispatcher(msg):
                 return self.dispatch_queue(stream, msg)
             return dispatcher
         
         for s in self.shell_streams:
             s.on_recv(make_dispatcher(s), copy=False)
             s.on_err(printer)
         
         if self.iopub_stream:
             self.iopub_stream.on_err(printer)
         
         #### while True mode:
         # while True:
         #     idle = True
         #     try:
         #         msg = self.shell_stream.socket.recv_multipart(
         #                     zmq.NOBLOCK, copy=False)
         #     except zmq.ZMQError, e:
         #         if e.errno != zmq.EAGAIN:
         #             raise e
         #     else:
         #         idle=False
         #         self.dispatch_queue(self.shell_stream, msg)
         #             
         #     if not self.task_stream.empty():
         #         idle=False
         #         msg = self.task_stream.recv_multipart()
         #         self.dispatch_queue(self.task_stream, msg)
         #     if idle:
         #         # don't busywait
         #         time.sleep(1e-3)