Example 3: A workflow with scatter and follow

Workflow definition

{  "workflow_id": "example3",  "config": {},  "tasks": [    {      "id": "1",      "execution_configurations" : [        {          "function_def_id" : "firstFunc",          "priority" : 1        }      ],      "successors": [        "2"      ],      "properties": {        "position": "start"      }    },    {      "id": "2",      "execution_configurations" : [        {          "function_def_id" : "multFunc",          "priority" : 1        }      ],      "successors": [        "3"      ],      "properties": {        "scatter": "predecessor_outputs['1']['tile']"      }    },    {      "id": "3",      "execution_configurations" : [        {          "function_def_id" : "otherFunc",          "priority" : 1        }      ],      "successors": [],      "properties": {        "follow": "2"      }    }  ]}

If the function firstFunc generates the same output as the examle above, and task 2 is expanded in the same manner:

Then task 3 will be expanded to tasks 3_A, 3_B, 3_C, each of which becomes a successor of one of the tasks expanded from task 2:

DAG representation

Task 2 is a scatter task: Upon expansion of task 2, task 3 is expanded into 3 tasks: 3_A, 3_B and 3_C.