.. _Orchestrator:

Orchestrator
------------

Orchestrator does the ... Orchestration.

You can use the class in your Lambda as is, just configure some settings using one of the
supported ways in :ref:`Config <components-config>`

The following diagram represents the basic Task Workflow initiated by the Orchestrator.

.. figure:: ../_static/images/orchestrator-invocation.png
   :alt: Invocation Process
   :align: center

   Workers Invocation Workflow


.. code-block:: python

   TASKS_TABLE_CONFIG = {
       'row_mapper':       {
           'task_id':             'S',
           'labourer_id':         'S',
           'greenfield':          'N',
           'attempts':            'N',
           'closed_at':           'N',
           'completed_at':        'N',
           'desired_launch_time': 'N',
           'arn':                 'S',
           'payload':             'S'
       },
       'required_fields':  ['task_id', 'labourer_id', 'created_at', 'greenfield'],
       'table_name':       'sosw_tasks',
       'index_greenfield': 'sosw_tasks_greenfield',
       'field_names':      {
           'task_id':     'task_id',
           'labourer_id': 'labourer_id',
           'greenfield':  'greenfield',
       }
   }

   TASK_CLIENT_CONFIG = {
       'dynamo_db_config':                  TASKS_TABLE_CONFIG,
       'sosw_closed_tasks_table':           'sosw_closed_tasks',
       'sosw_retry_tasks_table':            'sosw_retry_tasks',
       'sosw_retry_tasks_greenfield_index': 'labourer_id_greenfield',
       'ecology_config':             {},
       'labourers':                         {
           'some_function': {
               'arn':                          f"arn:aws:lambda:us-west-2:737060422660:function:some_function",
               'max_simultaneous_invocations': 10,
               'health_metrics':               {
                   'SomeDBCPU': {
                       'details':                     {
                           'Name':       'CPUUtilization',
                           'Namespace':  'AWS/RDS',
                           'Period':     60,
                           'Statistics': ['Average'],
                           'Dimensions': [
                               {
                                   'Name':  'DBInstanceIdentifier',
                                   'Value': 'YOUR-DB'
                               },
                           ],
                       },

                       # These is the mapping of how the Labourer should "feel" about this metric.
                       # See EcologyManager.ECO_STATUSES.
                       # This is just a mapping ``ECO_STATUS: value`` using ``feeling_comparison_operator``.
                       'feelings':                    {
                           3: 50,
                           4: 25,
                       },
                       'feeling_comparison_operator': '<='
                   },
               },
           },
       },
   }

   ORCHESTRATOR_CONFIG = {
       'task_config': TASK_CLIENT_CONFIG,
   }


Example `CloudFormation template for Orchestrator`_

See also :ref:`Greenfield`

.. automodule:: sosw.orchestrator
   :members:


.. _CloudFormation template for Orchestrator: https://raw.githubusercontent.com/sosw/sosw/master/examples/essentials/sosw_orchestrator/sosw-orchestrator.yaml