Introducing the Rule Builder Control for SAP UI5

A SAP business rule is a logic that defines some aspect of a business and always resolves to a boolean value of true or false. Non-technical users can maintain this logic through a simplified rules language and user interface. Thus, business rules allow clients of the application to add their own logic without requiring technical customization or coding.

The rule builder control allows business users to create and edit business rules in the application based on SAP UI5. This control defines the SAP standard UX for creating business rules in SAP Fiori applications and should be the default UI component for SAP Fiori UI developers to add business rules functionality.

The ui library provides controls for managing business rules. The two main components are:

• RuleBuilder - Provides rule visualization in the form of decision tables and text rules to simplify the creation and editing of rule business logic.
• Expression Language Services - Provides Expression Language services to support readability and correctness of business rules.

The visualizations provided by the RuleBuilder component contain text parts, and the Expression Language Service enables end users to create and edit these text parts.

Expression Languages

Developers can model rules using an expression language. The rule builder supports two expression languages:

• Expression Language 1.0 (also known as Regular Expression Language): Expression Language 1.0 enables users to define business decision logic with a simple and easy-to-read syntax. This is the default language supported by the rule builder. A typical rule condition in Expression Language 1.0 is as follows:

customer_name of the customer is equal to 'John

• Expression Language 2.0 (DMN SFEEL): Expression Language 2.0 or DMN SFEEL is a subset of Friendly Enough Expression Language (FEEL) that provides a standard syntax for rule conditions and reduces ambiguity when modeling rules. A typical rule condition in Expression Language 2.0 is as follows:

customer.customer name MATCHES 'John'