Data flow makes it possible to share data between different tasks in a workflow instance.

A task can have one or more input and output mappings to control the data which is mapped into and out of the task.

name: order-process

tasks:
    - id: collect-money
      type: payment-service
      outputs:
          - source: $.totalPrice
            target: $.totalPrice

    - id: fetch-items
      type: inventory-service

    - id: ship-parcel
      type: shipment-service
      inputs:
          - source: $.shippingAddress
            target: $.address

Each mapping has a source and a target property in form of a JSON path expression. The source property defines how the value is extracted and the target property defines how the value is inserted in the payload.

Read more about input and output mappings.