Step Inputs and Outputs
Each step in a process has information that flows into and out of it. Information flowing into a step is called input, and information flowing out of a step is called output. A process itself can also have inputs and outputs, such as when calling a process from a call activity step.
Process data assigned in Designer to flow in and out of steps needs to be mapped to physical data that the underlying services require in order for the process to execute.
Step inputs and outputs are used to define flow signatures, branching and looping logic in the process and data logging for examination at run time.
Step inputs and outputs are used to generate the signatures for the generated services that implement the process. If the underlying implementation of the step requires different physical data than this process data, the data must be mapped in the generated flows.
Process data follows a pipeline model, where all data that is input to a step must be output upstream in the process from that step.
Data can therefore enter the process in two ways:
In a receive step, a subscription document can trigger or join the process, and output data for that step and into the pipeline
In an activity step, the step can output new process data into the pipeline
While you can add new inputs to any step, the process will not be valid (for example, ready to be built) until all step inputs are first selected as outputs of an upstream receive or activity step.
Designer can automatically map inputs and outputs in the following circumstances:
Step A is linked to step B, and the output of step A has the same name as the input of step B
An activity step input name is the same as the document or service input name
A Receive Task output document is the same type as its incoming document type
In all but these cases, you must manually map step input and output data.