def __init__ (self, _adaptor, _method_type, _method_context, _ttype) :
"""
This saga.Task constructor is private.
``_adaptor`` references the adaptor class instance from which this
task was created via an asynchronous function. Note that the API level
object instance can be inferred via ``_adaptor.get_api ()``. Further, the
adaptor will reference an _adaptor._container class, which will be
considered the target for bulk operations for this task.
``_method_type`` specifies the SAGA API method which task is
representing. For example, for the following code::
d = saga.filesystem.Directory ("file:///")
t = d.copy ('/etc/passwd', '/tmp/passwd.bak', saga.task.ASYNC)
The resulting task ``t`` would represent the *'copy'* method. This is
required to forward :class:`saga.task.Container` calls to the correct
bulk method, in this case ``container_copy()``.
``_method_context`` describes the context in which the task method is
running. It is up to the creator of the task to provide that context --
in general, it will at least include method parameters.
``ttype`` determines in what state the constructor will leave the task:
``DONE`` for ``ttype=SYNC``, ``RUNNING`` for ``ttype=ASYNC`` and ``NEW``
for ``ttype=TASK``.
If the ``_method_context`` has *exactly* two elements, names ``_call``
and ``args``, then the created task will wrap
a :class:`saga.util.threads.Thread` with that ``_call (_args)``.
"""
self._base = super (Task, self)
self._base.__init__ ()
self._thread = None
self._ttype = _ttype
self._adaptor = _adaptor
self._method_type = _method_type
self._method_context = _method_context
# set attribute interface properties
self._attributes_allow_private (True)
self._attributes_extensible (False)
self._attributes_camelcasing (True)
# register properties with the attribute interface
self._attributes_register (RESULT, None, satt.ANY, satt.SCALAR, satt.READONLY)
self._attributes_set_getter (RESULT, self.get_result)
self._attributes_set_setter (RESULT, self._set_result)
self._attributes_register (EXCEPTION, None, satt.ANY, satt.SCALAR, satt.READONLY)
self._attributes_set_getter (EXCEPTION, self.get_exception)
self._attributes_set_setter (EXCEPTION, self._set_exception)
self._attributes_register (STATE, UNKNOWN, satt.ENUM, satt.SCALAR, satt.READONLY)
self._attributes_set_enums (STATE, [UNKNOWN, NEW, RUNNING, DONE, FAILED, CANCELED])
self._attributes_set_getter (STATE, self.get_state)
self._attributes_set_setter (STATE, self._set_state)
self._set_state (NEW)
# check if this task is supposed to wrap a callable in a thread
if '_call' in self._method_context :
if not '_args' in self._method_context :
self._method_context['_args'] = ()
if not '_kwargs' in self._method_context :
self._method_context['_kwargs'] = {}
if 3 != len (self._method_context) :
raise se.BadParameter ("invalid call context for callable task")
call = self._method_context['_call']
args = self._method_context['_args']
kwargs = self._method_context['_kwargs']
self._thread = Thread (call, *args, **kwargs)
# ensure task goes into the correct state
if self._ttype == SYNC :
self.run ()
self.wait ()
elif self._ttype == ASYNC :
self.run ()
elif self._ttype == TASK :
pass
class Task (sbase.SimpleBase, satt.Attributes) :
# --------------------------------------------------------------------------
#
@sus.takes ('Task',
sab.Base,
basestring,
dict,
sus.one_of (SYNC, ASYNC, TASK))
@sus.returns (sus.nothing)
def __init__ (self, _adaptor, _method_type, _method_context, _ttype) :
"""
This saga.Task constructor is private.
``_adaptor`` references the adaptor class instance from which this
task was created via an asynchronous function. Note that the API level
object instance can be inferred via ``_adaptor.get_api ()``. Further, the
adaptor will reference an _adaptor._container class, which will be
considered the target for bulk operations for this task.
``_method_type`` specifies the SAGA API method which task is
representing. For example, for the following code::
d = saga.filesystem.Directory ("file:///")
t = d.copy ('/etc/passwd', '/tmp/passwd.bak', saga.task.ASYNC)
The resulting task ``t`` would represent the *'copy'* method. This is
required to forward :class:`saga.task.Container` calls to the correct
bulk method, in this case ``container_copy()``.
``_method_context`` describes the context in which the task method is
running. It is up to the creator of the task to provide that context --
in general, it will at least include method parameters.
``ttype`` determines in what state the constructor will leave the task:
``DONE`` for ``ttype=SYNC``, ``RUNNING`` for ``ttype=ASYNC`` and ``NEW``
for ``ttype=TASK``.
If the ``_method_context`` has *exactly* two elements, names ``_call``
and ``args``, then the created task will wrap
a :class:`saga.util.threads.Thread` with that ``_call (_args)``.
"""
self._base = super (Task, self)
self._base.__init__ ()
self._thread = None
self._ttype = _ttype
self._adaptor = _adaptor
self._method_type = _method_type
self._method_context = _method_context
# set attribute interface properties
self._attributes_allow_private (True)
self._attributes_extensible (False)
self._attributes_camelcasing (True)
# register properties with the attribute interface
self._attributes_register (RESULT, None, satt.ANY, satt.SCALAR, satt.READONLY)
self._attributes_set_getter (RESULT, self.get_result)
self._attributes_set_setter (RESULT, self._set_result)
self._attributes_register (EXCEPTION, None, satt.ANY, satt.SCALAR, satt.READONLY)
self._attributes_set_getter (EXCEPTION, self.get_exception)
self._attributes_set_setter (EXCEPTION, self._set_exception)
self._attributes_register (STATE, UNKNOWN, satt.ENUM, satt.SCALAR, satt.READONLY)
self._attributes_set_enums (STATE, [UNKNOWN, NEW, RUNNING, DONE, FAILED, CANCELED])
self._attributes_set_getter (STATE, self.get_state)
self._attributes_set_setter (STATE, self._set_state)
self._set_state (NEW)
# check if this task is supposed to wrap a callable in a thread
if '_call' in self._method_context :
if not '_args' in self._method_context :
self._method_context['_args'] = ()
if not '_kwargs' in self._method_context :
self._method_context['_kwargs'] = {}
if 3 != len (self._method_context) :
raise se.BadParameter ("invalid call context for callable task")
call = self._method_context['_call']
args = self._method_context['_args']
kwargs = self._method_context['_kwargs']
self._thread = Thread (call, *args, **kwargs)
# ensure task goes into the correct state
if self._ttype == SYNC :
self.run ()
self.wait ()
elif self._ttype == ASYNC :
self.run ()
elif self._ttype == TASK :
pass
# --------------------------------------------------------------------------
#
@sus.takes ('Task')
@sus.returns (sus.nothing)
def run (self) :
if self._thread :
self._thread.run ()
else :
# FIXME: make sure task_run exists. Should be part of the CPI!
self._adaptor.task_run (self)
# --------------------------------------------------------------------------
#
@sus.takes ('Task',
float)
@sus.returns (sus.nothing)
def wait (self, timeout=None) :
if None == timeout :
timeout = -1.0 # FIXME
if self._thread :
self._thread.wait () # FIXME: timeout?!
self._set_state (self._thread.state)
else :
# FIXME: make sure task_wait exists. Should be part of the CPI!
self._adaptor.task_wait (self, timeout)
# ----------------------------------------------------------------
#
@sus.takes ('Task')
@sus.returns (sus.nothing)
def cancel (self) :
if self._thread :
self._thread.cancel ()
self._set_state (CANCELED)
else :
# FIXME: make sure task_cancel exists. Should be part of the CPI!
self._adaptor.task_cancel (self)
# --------------------------------------------------------------------------
#
@sus.takes ('Task',
sus.one_of (UNKNOWN, NEW, RUNNING, DONE, FAILED, CANCELED))
@sus.returns (sus.nothing)
def _set_state (self, state) :
if not state in [UNKNOWN, NEW, RUNNING, DONE, FAILED, CANCELED] :
raise se.BadParameter ("attempt to set invalid task state '%s'" % state)
self._attributes_i_set (self._attributes_t_underscore (STATE), state, force=True)
# --------------------------------------------------------------------------
#
@sus.takes ('Task')
@sus.returns (sus.one_of (UNKNOWN, NEW, RUNNING, DONE, FAILED, CANCELED))
def get_state (self) :
if self._thread :
self._set_state (self._thread.state)
return self.state
# --------------------------------------------------------------------------
#
@sus.takes ('Task',
sus.anything)
@sus.returns (sus.nothing)
def _set_result (self, result) :
self._attributes_i_set (self._attributes_t_underscore (RESULT), result, force=True)
self._attributes_i_set (self._attributes_t_underscore (STATE), DONE, force=True)
# --------------------------------------------------------------------------
#
@sus.takes ('Task')
@sus.returns (sus.anything)
def get_result (self) :
if not self.state in [DONE, FAILED, CANCELED] :
self.wait ()
assert (self.state in [DONE, FAILED, CANCELED])
if self.state == FAILED :
self.re_raise ()
return
if self.state == CANCELED :
raise se.IncorrectState ("task.get_result() cannot be called on cancelled tasks")
if self.state == DONE :
if self._thread :
self._set_result (self._thread.result)
return self.result
# --------------------------------------------------------------------------
#
@sus.takes ('Task',
se.SagaException)
@sus.returns (sus.nothing)
def _set_exception (self, e) :
self._attributes_i_set (self._attributes_t_underscore (EXCEPTION), e, force=True)
# --------------------------------------------------------------------------
#
@sus.takes ('Task')
@sus.returns (se.SagaException)
def get_exception (self) :
if self._thread :
self._set_exception (self._thread.exception)
return self.exception
# --------------------------------------------------------------------------
#
@sus.takes ('Task')
@sus.returns (sus.nothing)
def re_raise (self) :
if self.exception :
raise self.exception