About processes and subprocesses

Processes

A process is a single workflow within a configuration (see About Workflow Configurations). A process begins with a single input task, contains one or more tasks and/or branches, and terminates with one or more output tasks. In its simplest form, a process can retrieve data from a given folder and save it in a different folder. In most cases, though, processes are more elaborate and configurations, which may include many processes, can be extremely complex.

PlanetPress Workflow processes act as dispatchers: on the one hand, they retrieve data and control plugins that retrieve data from watched locations, and on the other hand they can perform a variety of operations on the data and send data to various devices.
A given process may include Output tasks that generate files used by Input tasks from other processes.
Each process’s schedule determines when its initial input task can be performed. Other tasks included in the process are performed regardless of schedule, granted that the previous task was performed.

The available processes in your PlanetPress Workflow Configuration are listed in the Configuration Components pane. Processes in a configuration will always run concurrently. You can schedule processes to run only at certain times or intervals (see Process properties).

There are three types of processes available to you:

• A normal process will run as soon as an input file is available through its input task or, if it is scheduled not to run at that time, will start processing as soon as the schedule permits it.
• Startup processes are processes that run only once before every other process in a given configuration. They can be used to perform operations that need to be completed once before the configuration can actually be run, such as to map network drives. You may only have one single startup process in your configuration.
• Subprocesses are processes which can be called by any other process from any action task. They can be used to perform and reuse redundant operations that may need to be executed numerous times.

Process properties

Regular and startup processes can be set to be Active (process runs normally) or Inactive (process will not run at all); see Activating or deactivating a process.
To learn how to set other properties of processes, such as their schedule, see Process properties.

Special workflow types

PlanetPress Workflow supports multiple input and output types, in so many different combinations that it would be hard to give example processes for each possibility. However, some types of processes like HTTP and PDF processes will probably be used more often than other types of processes. You will find a description of each of these special workflow types and at least one example of an implementation that uses them in the chapter: Special workflow types.

Subprocesses

Subprocesses are special processes that can be called by any other process. These act exactly as subroutines in programming languages, allowing users to reuse existing processes by sharing them to the whole configuration file. They can thus be used to perform redundant operations that may need to be executed numerous times; for instance, archiving a copy of a zipped file received as the input job file, then decompressing it before sending the unzipped version of it back to the calling process.

To call a subprocess from another process, use the Go Sub Action task.

Whenever a process calls a subprocess, the main process (the caller) will wait for the called subprocess to finish its execution before carrying on with its own. This means the subprocess feature is synchronous with the main process. This also means the calling process actually appends the subprocess to its own workflow.

• Last Topic Update: Aug-21-2018 - 10:08
• Last Published: Sep-17-2019 - 09:09