Process Manager - DMN task

To use DMN Tasks, Workflow Accelerator needs to be linked to Process Manager, read more in the section Integrating Signavio Process Manager with Workflow Accelerator .

DMN (Decision Model and Notation) is suitable for business decisions that follow a rule-based decision logic.

With DMN tasks DMN task, you can execute the decision logic from a DMN diagram in Workflow Accelerator. You create the DMN diagram in Process Manager.

Creating a DMN diagram in Process Manager

  1. Create a DMN diagram, see Creating and editing DMN diagrams .

  2. Publish the DMN diagram in Collaboration Hub, see DMN diagrams in Collaboration Hub . The published DMN diagram can be used for a DMN task in Workflow Accelerator.

You can test the decision logic in Collaboration Hub, read more in section Simulating DMN diagrams in Collaboration Hub: The Decision Assistant . If the simulation shows an invalid decision, the decision cannot be used for DMN tasks.

Limitations

The following limitations apply for DMN diagrams to use with DMN tasks:

  • Multi-hit policies can be used, with the exception of the Output order hit policy (see Hit policies).
  • Only decision diagrams with a single top-level decision can be used (this is the decision used by the DMN task).
  • Multi-instance decisions and DMN diagrams that include linked decisions cannot be used in DMN tasks.

Configuring the DMN task in Workflow Accelerator

In the process builder, drag the DMN task actionDMN task either from the collapsed actions palette or from the drop-down list of Process Manager actions.

  1. Build a process with a DMN task action.

  2. In the configuration panel of the DMN task, select a DMN Diagram to use.

    • The published revision and the Decision is inserted automatically.

  3. Select the necessary Inputs and Outputs.

  4. Add an element to the process that uses the output of the decision. The most common use is an exclusive gateway with an automatic decision, based on the output of the DMN task.

Updating the DMN task

When a new revision of the DMN diagram is published in Process Manager, the DMN task is not updated automatically.

If a new revision is available, you see an update suggestion in the configuration panel of the DMN task.

To update the DMN task, follow these steps:

  1. In the configuration panel of the DMN task,click the link informing you about a new revision.

    • The revision is updated.
    • The Decision is inserted automatically.
  2. If necessary, change the Inputs and Outputs.

  3. Publish the new process version.

    • The updated DMN task is used for new cases.

Running cases are not affected by the update.

If the logic of the DMN diagram was changed, it can be necessary to change the process to match the new logic. Inputs and outputs are reset if they no longer fit the new revision.

  • The update suggestion in the configuration panel is the only notification for updated revisions.
  • If you don't update the DMN task, the previous revision is used when starting cases.

Removing a decision from a DMN task

You can select a different decision for an existing DMN task or delete a DMN task to no longer use a decision in a workflow.

To remove a decision completely, so that it no longer can be selected for DMN tasks, delete the decision in Process Manager. Empty the trash folder to remove the decision completely. While the decision is still in the trash folder, the decision can be used for DMN tasks.

You can't change an existing DMN rule task to a DMN task.

Example

You can use DMN diagrams for decisions like:

  • Does this customer receive a discount?

  • Does this expense comply with tax regulations?

  • Does this order qualify for a free gift?

In the following example, the decision modeled with DMN is "Does this customer qualify for gold status?". The process with the DMN task uses this decision for further actions.

First create a DMN diagram named Status evaluation in Process Manager.

The customer is rewarded Gold status for a certain number of status points. Since the number of status points is the deciding factor, this number is the input for the decision. The decision element is named Gold status? in this example.

Add a DMN element with one input, Number of status points. The decision logic follows two rules, one for fewer than 1800 points and one for 1800 points and more. Add the rules to the Decision table.

DMN diagram with one input
DMN diagram with one input
Decision logic table with two rules
Decision logic table with two rules

The annotations are not visible in Workflow Accelerator.

After you have added the decision logic, publish the diagram in Collaboration Hub.

Now use Workflow Accelerator to build a new process Determine customer status.

Determine customer status process
Determine customer status process

To set up the DMN task in the process, open the configuration panel of the DMN task. Select the DMN diagram Status evaluation. You can see the revision, the Decision is found automatically.

The only Input in this example is Number of status points. The Output, used by the exclusive gateway, is Gold membership?.

Now you can publish the process and start a case.