What Is a Flow Step?

A flow service contains flow steps. A flow step is a basic unit of work (expressed in the webMethods flow language) that webMethods Integration Server interprets and executes at run time. The webMethods flow language provides flow steps that invoke services and flow steps that let you edit data in the pipeline.

Invocation Steps
INVOKE	Executes a specified service. For more information about this step, see The INVOKE Step.
Data-Handling Steps
MAP	Performs specified editing operations on the pipeline (such as mapping variables in the pipeline, adding variables to the pipeline, and dropping variables from the pipeline). For more information about this step, see The MAP Step.
Control Steps
BRANCH	Executes a specified flow step based on the value of a specified variable in the pipeline. For more information about this step, see The BRANCH Step.
LOOP	Executes a set of flow steps once for each element in a specified array. For more information about this step, see The LOOP Step.
REPEAT	Re-executes a set of flow steps up to a specified number of times based on the successful or non-successful completion of the set. For more information about this step, see The REPEAT Step.
SEQUENCE	Groups a set of flow steps into a series. The SEQUENCE step is implicit in most flow services (that is, the steps in a flow service are treated as a series). However, at times it is necessary to explicitly group a subset of flow steps using SEQUENCE so that they can be treated as a unit. For more information about this flow step, see The SEQUENCE Step.
EXIT	Controls the execution of a flow step (for example, abort an entire flow service from within a series of deeply nested steps, throw an exception without writing a Java service, or exit a LOOP or REPEAT without throwing an exception). For more information about this step, see The EXIT Step.