Using a Configuration Variable to Control a Process Flow

In this example, we demonstrate how a workflow can be adjusted during runtime with the help of a configuration variable value.

Assuming a company has a workflow, where they do not require a specific activity to be executed in a test environment, but they do want it to be executed in production. To achieve such a behavior, we create a model having a configuration variable. If this variable is set to a specific value, the activity foreseen for production only is executed, otherwise skipped. The variable is checked via a transition condition in the model. Testing the example is done in the Stardust Portal, where we change the variable in the Configuration Variables view.

You can create the model as described in the following section, or import the completed example model provided by Stardust. Therefore download the following ZIP file containing the configuration variables example model:

config-variables.zip

Creating the Model

In a dynamic Web project designed to deploy Stardust models to run in the Stardust Portal, create a model, e.g. ProductionOrTestVarDemo. For detailed information on creating dynamic Web projects for usage with the Stardust Portal, please refer to the Rapid Application Development guide.

Proceed as follows:

Adding the Configuration Variable

To add the configuration variable:

  1. Open the model properties page.
  2. Click on Configuration Variables.
  3. Click Add.
  4. Click in the Name column and enter the variable name Environment.
  5. Enter TEST as default value in the Default Value column entry field.
  6. Optionally add a description.

Add variable Environment.
Figure: Add variable Environment.

Please refer to chapter Using Configuration Variables in the Modeling Guide for details on adding variables to a model.

Creating the Workflow

  1. Create a manual trigger followed by a manual activity Starting Activity.
  2. Right-click the activity and select Split Behavior > XOR.

  3. Create an activity named Activity Production Only. This will be the activity to be performed in production mode only.
  4. Create another activity Continue to be performed after the production activity or from the starting activity directly.
  5. Add a role to the model and assign it as performer of all activities and the manual trigger. For detailed information on how to add roles and assign them, please refer to chapter Defining Roles and Organizations of the Support Case Example.
  6. Create a connection from the split joint of activity Starting Activity to activity Activity Production Only and one to activity Continue, as illustrated in the following screenshot:

  7. Enter a condition transition to the transition from the split joint to Activity Production Only by double-clicking the transition line in the diagram.
  8. In the transition condition property page dialog, enter the following Condition Expression: 
    "${Environment}" == "PRODUCTION";
    To refer to the value of the variable, the variable name is escaped as $"Environment".

This reference to the variable via the transition condition is reflected in the Configuration Variables section of the model property page. Open the model property page and switch to the Configuration Variable section. In the References part, the transition and its condition referencing to our Environment variable are displayed.

Running the Workflow with Different Variable Values

Now we will test our workflow in the Stardust Portal with different values of the configuration variable.

Running the Workflow in Test Mode

First we run the model workflow with the default value TEST.

  1. Start your server and deploy the model. For details on how to deploy a model, please refer to the chapter Deploying a Workflow Model of the Support Case Example.
  2. Start the Stardust Portal as described in the chapter Logging to the Stardust Portal of the End User Handbook. Login as administrator (motu/motu). You can use the Shift-F8 short key.
  3. Switch to the Participant Management View of the Administration Perspective.
  4. Create a user and assign him to the role we added to the model. For details on how to create a new user, refer to section Creating a new User of chapter Creating and Editing User Accounts of the Stardust Portal documentation.
  5. Logout and login again as the new user.
  6. In the Workflow Perspective, start the available process.
  7. Complete activity Starting Activity.

  8. Per default, the model is run in test mode as the default value of the configuration variable is "TEST" (or different to "PRODUCTION"). Thus, the activity Activity Production Only is skipped and activity Continue is opened.

Switching to Production Mode

To run the model workflow in production mode, we change the value of our configuration variable to PRODUCTION. Therefore we need to perform the following steps:

  1. Switch to the Configuration Variables view in the Administration Perspective.

    For details on this view, please refer to chapter Viewing and Editing Configuration Variables of the Stardust Portal guide.
  2. In the Value column, change the value of the variable to "PRODUCTION".

  3. A red little star in the upper right corner of the Value entry field indicates that the variable has been changed but not saved. Click the Change button in the upper-right corner to save the new configuration variable value:

    The red star now disappears

  4. Now start the process again.
  5. Complete activity Starting Activity.
  6. The transition condition checks the value of the variable and decides to run the activity foreseen for production. Thus, the next activity opening is Activity Production Only.
  7. Completing this activity results in continuing with activity Continue.

The value of the variable is stored in later versions of this process model. In case you want to run the model again in test mode and skip the activity for production, change the variable value to "TEST" accordingly.