Shape

Shapes are the visual building blocks of Frends Processes. All of the elements in a Process, regardless of their type, are commonly called shapes. This term is used in BPMN notation as well to describe the elements in a process diagram.

It should also be noted that not all BPMN shapes are usable in Frends. Frends uses a specialized subset of BPMN elements to create integration flows, and includes functionality to many of them that are not part of BPMN notation. The combination of BPMN notation and included functionality is what makes Frends' Process Editor the easy to use tool to create visually informative processes.

Types of Shapes

Shapes used in Frends Processes can be split into few different categories.

Event shapes

Event shapes are category of elements in BPMN, where they either start the process, ie. listen to events, or raise an event elsewhere and optionally stopping a process.

In Frends, event shapes are used for all of these situations. Trigger shape is used to start a Process, Return and Throw are used to end a Process, and Intermediate Return is used to send an response to caller before execution is complete. Catch is also used to listen to thrown errors within the Process, for error handling.

Learn more about event shapes here.

Decision shapes

Decision shapes can be used in both BPMN and Frends to create conditional paths in the Processes. Of the various shapes available in BPMN, Frends utilises two: Exclusive Decision and Inclusive Decision.

Exclusive Decision is the standard if-else-statement from general programming. A single condition is given, and it has to be either true or false, to choose a path from the two available.

For Inclusive Decision, each path is given a condition. Execution can follow only one path in Process, or split into multiple paths if multiple conditions are true. It's also possible that none of the conditions are fulfilled, making the Process skip the paths altogether, using an implicit "no action" path to the point where the paths converge again.

Learn more about decision shapes here.

Activity shapes

Activity shapes are the elements which perform actual computation in Processes. While in Frends the Task name is used most often specifically for our pre-made connectors or activities that can be used to do a lot of tasks without any extra programming required, Task also means the other shapes used to perform predefined actions in a Process.

In addition to Tasks, activity shapes in Frends include Call Subprocess to execute Subprocesses within the Process, Code Task and Assign Variable shapes to run your own C# code, as well as Shared State Task and DMN Task, to use local cache and to perform complex decisions using Decision Model and Notation syntax, respectively.

Learn more about activity shapes here.

Scope shapes

Scope shapes are used in Frends to both logically separate functionality into different blocks, as well as perform iteration.

Scope shape is used to define a named scope within a Process, allowing for example error handling to catch errors from that area of Process specifically, and not interrupting the whole Process execution. It can be thought of as using curly brackets in standard programming.

Similarly to default Scope shape, Foreach and While Scope shapes are used create a scope within your Process, but in addition they perform Foreach and While iterations like their name implies. Foreach can be used to iterate over a whole array or list of items and perform actions for each element sequentially, while the While shape can be used to iterate until the specified condition no longer holds true. As a safeguard to avoid infinite loops, the While shape includes a max iterations field, which will raise an error in case the specified number of iterations is reached.

Learn more about Scope shapes here.

Artifact shapes

To enhance the visual presentation of Processes, a few purely documentational shapes are included to better visualize and explain Process functionality, similarly to comments in general programming languages. While they are a part of each Process and can be connected to any shape at any point in the Process using data or message flows, artifacts do not participate in the Process execution in any way.

Learn more about artifact shapes here.

Sequence flow shape

Sequence flows are the arrows connecting different shapes in a process together, to form a Process. Instead of Sequence flows, Message flows are also used with the artifact shapes to visually connect the descriptive shapes into shapes of the Process, optionally showing the data flow direction if data object or data store reference shapes are used.

When used with conditions, especially inclusive decision shape, the sequence flows also include the condition for each path. Default path can also be specified when used with either decision shape, signifying the path to take if conditions are not fulfilled.

Because Frends utilises BPMN notation to create integration flows, Sequence flow in Frends means an arrow connecting different shapes together. It should not be mixed up with connectors in integrations in general, as those are more alike Tasks in Frends, while sometimes connector in Frends might be used to mean a Sequence flow.

Learn more about sequence flow shape here.