Process variables

Variables play a critical role in workflows by dynamically storing and passing data. This enables workflows to adapt to user input, system states, or external data.

Variables act as placeholders for data that you can dynamically assign, modify, or retrieve during the execution of a workflow. They allow workflows to respond to specific conditions, user inputs, or system states, making workflows more flexible and interactive.

For example, a variable can store:

  • User input from a form, such as a due date entered by a user.
  • Dynamic data retrieved from Collibra assets, such as the name of an asset.
  • System-generated values, such as timestamps or IDs.

Setting process variables

Process variables originate from various sources:

  • The start event initiator: The value you provide as the Initiator variable of the start event becomes one of the first variables, defining the user who starts the workflow. By default, the value is initiator and user tasks are automatically assigned to this candidate through the expression user(${initiator}).
  • User task form fields: In user tasks, any data entry or selection component that a user interacts with becomes a process variable. You use the Value property of the component to reference this variable.
  • Script task variables:
    • The scope of the variables you declare in a script task is limited to that script. However, you can set process variables, which become available outside the script, using execution.setVariable(<variable_name>, <varaible_value>);, where <variable_name> is a String and <variable_value> is an object.
    • Workflow beans: Built-in context variables that provide information about the context in which the workflow is running, such as users.current or item.type.

    • API interfaces: Interfaces such as AssetApi, UserApi, and FileApi are pre-instantiated and accessible via variables such as assetApi, userApi, and fileApi.

  • Configuration variables: When you deploy a workflow, Collibra automatically adds a series of default configuration variables for each user task. These include duration variables for the due dates and escalation durations, in addition to any configuration variables you might have set.

Reserved variable names

When working with variables in workflows, it is important to be aware of reserved variable names. These are predefined variables that Collibra uses, and they cannot be overridden or redefined in your workflows. Using these reserved names for custom variables can lead to unexpected behavior or errors:

  • escalationType
  • event
  • eventResourceId
  • eventResourceType
  • eventTaskCandidates
  • eventTaskId
  • eventTaskKey
  • eventType
  • eventV1
  • eventV2
  • initiator
  • isApiV2Workflow
  • item
  • itemCommunity
  • itemResourceId
  • itemResourceType
  • itemV1
  • itemV2
  • itemVocabulary
  • mail
  • users
  • usersV1
  • usersV2
  • workflowDefinitionName
  • workflowStartUserId

Retrieving process variables

You can retrieve process variables in several ways, depending on where this action occurs:

  • In script tasks: You have direct access to all process variables. You can also explicitly retrieve a variable with execution.getVariable(<variable_name>);, where <variable_name> is a String.
  • In other process components: Use JUEL expressions to access variables, such as ${myVariable}.
  • In form components: Unless otherwise noted, retrieve the value of a variable by including the variable name in a form expression: {{}}, for example {{initiator}}.

Exchanging process variables with a sub-process

Sub-processes are workflows that run as part of a parent workflow. They are not designed to be stand-alone workflows. You must provide values for start form variables with the Required property set to true. Additionally, you may use sub-process variables in the parent workflow.

To exchange information between a parent workflow and a sub-process, configure the call activity in the parent workflow:

  • In the In section of the Variable Mapping properties, add items and:
    • Enter parent workflow process variables in the Source variable field.
    • Enter the corresponding sub-process variables in the Target variable field.
    • Use an expression in the Source Expression field if to pass a hard-coded, for example ${"Enter a brief description"} or ${false}.
  • In the Out section of the Variable Mapping properties, add items and:
    • Enter sub-process variables in the Source variable field.
    • Enter the corresponding parent workflow process variables in the Target variable field.

Since the parent workflow and the sub-process are separate workflows, you can use the same name for corresponding variables.

Important considerations

By understanding and leveraging variables effectively, you can create dynamic and responsive workflows in Collibra that cater to a wide range of business needs.

To maximize the potential of variables, consider the following:

  • Descriptive naming: Use clear and meaningful names, such as requestorName instead of rn.
  • Consistent naming conventions: Follow consistent patterns, for example camel case: usageRequestReason.
  • Scope and data type awareness: Understand where variables are accessible and their data types.
  • Variable validation: Implement validation where necessary to ensure data integrity.