Add a executor backed conductor and have existing impl. use it

This adds a executor backed job dispatching base class
and has the existing blocking executor use it by running jobs
and dispatching jobs into a sync executor. It also allows
for dispatching jobs into a thread executor, or other executor
via a new '_executor_factory' method that can generate
executors (it can be overriden in the non-blocking executor
to provide your own executors instances).

This does alter the behavior in that now that jobs are dispatched
into an executor we no longer can immediatly know if a job was
dispatched and raised an exception or whether it will raise an
exception in the future, so we now alter the 'local_dispatched'
to just be a boolean that is used to determine if any dispatches
happened (failure or not).

Change-Id: I485770e8f4c85d3833892a453c9fb5168d8f0407

1 files changed, 14 insertions, 0 deletions

diff --git a/taskflow/utils/misc.py b/taskflow/utils/misc.py
index aa89aa8..ca8faa5 100644
--- a/taskflow/utils/misc.py
+++ b/taskflow/utils/misc.py
@@ -22,6 +22,7 @@ import errno
 import inspect
 import os
 import re
+import socket
 import sys
 import threading
 import types
@@ -42,6 +43,7 @@ from taskflow.types import notifier
 from taskflow.utils import deprecation
 
 
+UNKNOWN_HOSTNAME = "<unknown>"
 NUMERIC_TYPES = six.integer_types + (float,)
 
 # NOTE(imelnikov): regular expression to get scheme from URI,
@@ -68,6 +70,18 @@ class StringIO(six.StringIO):
         self.write(linesep)
 
 
+def get_hostname(unknown_hostname=UNKNOWN_HOSTNAME):
+    """Gets the machines hostname; if not able to returns an invalid one."""
+    try:
+        hostname = socket.getfqdn()
+        if not hostname:
+            return unknown_hostname
+        else:
+            return hostname
+    except socket.error:
+        return unknown_hostname
+
+
 def match_type(obj, matchers):
     """Matches a given object using the given matchers list/iterable.