Jump to: navigation, search

Difference between revisions of "TaskFlow/Inputs and Outputs"

(Storage)
(Replaced content with "'''Revised on:''' {{REVISIONMONTH1}}/{{REVISIONDAY}}/{{REVISIONYEAR}} by {{REVISIONUSER}} The page was moved to developers documentation: http://docs.openstack.org/develo...")
 
(31 intermediate revisions by 2 users not shown)
Line 1: Line 1:
 
'''Revised on:''' {{REVISIONMONTH1}}/{{REVISIONDAY}}/{{REVISIONYEAR}} by {{REVISIONUSER}}
 
'''Revised on:''' {{REVISIONMONTH1}}/{{REVISIONDAY}}/{{REVISIONYEAR}} by {{REVISIONUSER}}
  
== Overview ==
+
The page was moved to developers documentation: http://docs.openstack.org/developer/taskflow/inputs_and_outputs.html
 
 
In taskflow there are multiple ways to design how your tasks/flows and engines get inputs  and produce outputs. This document will help you understand what those ways are and how to use those ways to accomplish your desired taskflow usage pattern as well as include examples that show common ways of providing input and getting output.
 
 
 
=== Task & Flow Inputs and Outputs ===
 
 
 
'''See:''' [[TaskFlow/Task_Arguments_and_Results|Task & Flow Arguments and Results]]
 
 
 
=== Engine Inputs and Outputs ===
 
 
 
==== Storage ====
 
 
 
The storage layer is how an engine persists flow and task details.
 
 
 
For more in-depth design details: [[TaskFlow/Persistence|persistence].
 
 
 
To initially pre-populate your engine with arguments (so that dependent tasks can immediatly start running) you can directly interact with the engine <code>load</code> or <code>run</code> to provide these needed inputs.
 
 
 
'''For example:'''
 
 
 
 
 
         
 
    >>> from taskflow import task
 
    >>> from taskflow import engines
 
    >>> from taskflow.patterns import linear_flow as lf
 
    >>>
 
    >>> class CatTalk(task.Task):
 
    ...  def execute(self, meow):
 
    ...    print meow
 
    ...
 
    >>> class DogTalk(task.Task):
 
    ...  def execute(self, woof):
 
    ...    print woof
 
    ...
 
    >>> flo = lf.Flow("cat-dog")
 
    >>> flo.add(CatTalk(), DogTalk())
 
    >>> engines.run(flo)
 
    Traceback (most recent call last):
 
      File "<stdin>", line 1, in <module>
 
      File "/usr/lib/python2.6/site-packages/taskflow/engines/helpers.py", line 110, in run
 
        engine.run()
 
      File "/usr/lib/python2.6/site-packages/taskflow/utils/lock_utils.py", line 51, in wrapper
 
        return f(*args, **kwargs)
 
      File "/usr/lib/python2.6/site-packages/taskflow/engines/action_engine/engine.py", line 104, in run
 
        raise exc.MissingDependencies(self._flow, sorted(missing))
 
    taskflow.exceptions.MissingDependencies: taskflow.patterns.linear_flow.Flow: cat-dog; 2 requires ['meow', 'woof'] but no other entity produces said requirements
 
 
 
==== Notifications ====
 

Latest revision as of 10:10, 28 March 2014

Revised on: 3/28/2014 by Akarpinska

The page was moved to developers documentation: http://docs.openstack.org/developer/taskflow/inputs_and_outputs.html