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Log Messages In Task
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Problem
=======

You want to write task messages to a persistent log file.



Solution
========

Get the reference to the Log interface by
calling :py:meth:`get_property` on the task and passing in :py:class:`TaskProperties.LOGGER <agiparallel.constants.TaskProperties.LOGGER>`.


.. literalinclude:: ..\..\..\code\HowTos\TaskLogging.py
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	:dedent: 8
	:lines: 7
	
With an instance of the Log interface, all log methods are written to the standard host log files by default.
To view the log files, see :ref:`viewing log files`.


.. literalinclude:: ..\..\..\code\HowTos\TaskLogging.py
	:language: python
	:linenos:
	:dedent: 8
	:lines: 8-10


.. literalinclude:: ..\..\..\code\HowTos\TaskLogging.py
	:language: python
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	:lines: 1-4,4,5-11,11,12-18



Discussion
==========

Logging can be important for debugging, tracing, and post-mortem analysis. The Log interface provides "free" logging within tasks.
The main advantage to using the Log interface versus a custom logging mechanism is that Log is tightly integrated with the existing logging infrastructure.
For instance, right clicking on a task within the monitoring applications displays the user log messages in the same logs as the host.


See Also
========

Reference
"""""""""

* :py:obj:`LOGGER <agiparallel.constants.TaskProperties.LOGGER>`

Other Resources
"""""""""""""""

* :ref:`viewing log files`