BMC Helix Innovation Studio provides an Expression Editor in the View designer, Process designer, and Rule designer that you can use to configure the data required for views, processes, and rules of an application. For example, you can provide an expression to configure the data of input map properties of a Call Activity in a Process designer.
Expression Editor in Process designer and Rule designer consists of the following sections:
- Expression builder where you build the expression
- Virtual keyboard
- Context based dictionary UI from where you can pick an expression of a process variable, a keyword, and an activity result.
Data dictionary UI
The following table describes the nodes in the Data dictionary UI:
The process variables that you define in the process definition are available in the Expression Editor. This includes the process input parameters, output parameters, and local variables.
If a process variable is a record, and has associations, the associations are available in the Expression Editor which help to navigate to the associated records without using query.
To use a dynamic variable in a string, you can simply type the
When you use any field, variable, or keyword within a string expression, it will be evaluated to the value at runtime. If you want to use the variable name and not its value in the expression, then add an escape character (\) to the expression.
The results of all the activities that have outputs are available in the Expression Editor. The results of all the activities are captured in the process context and you do not have to store an activity result by using the activity output mapping. You can use an expression to pass the activity result to other activities.
The keywords such as Server URL, Current date, Current date and time, Current Groups, and so on are available in the Expression Editor.
This node is available only if you have already defined an Error Boundary event earlier in the process.
You can use an expression to access the exception class and error number (for Java exception error), or error message (for business error) caught by the Error Boundary event.
|Email Receive Event Fields|
This node is available only when you are using the Email Receive Event in a rule.
The incoming mailbox attributes, such as mailbox name, email sent to, plain text body, and so on, are available in the Expression Editor.
Expression Editor examples
The following table illustrates Expression Editor examples:
|Configuration using Expression Editor||Example|
In Process designers and Rule designers, you can use regular expressions in a Qualification (condition).
In Rule Designers, you can configure expressions in Rule Qualification.
In Process designers, you can use expressions in the following components:
In the Process designers, expressions can be used only with the
The following characters are allowed in the expression:
|Configure an expression by using individual attributes from a JSON schema.|
Configure an expression by selecting the fields from the associated records.
Important: Only fields from one to one and one to many associations are supported.
|Configure an expression by using fields in the configured incoming mailbox.|
|Configure condition using an activity result.|
|Configure the expression by using error details caught by the Error Boundary event.|
Configure a condition to check if the security label for a record instance is updated.
Important: In Rule designer, the
For more information about configuring a condition to identify the changes in security label, see Identifying updates to the security label.
|Configure a selection field.|
|Server URL in user message.|
|Configure Start Process expression in a rule.|
|Symbols used in Expression Editor.|