Rule Chain Initialization Validator

The Rule Chain Initialization Validator is an important component used to verify whether the structure and configuration of a rule chain comply with relevant rules before the rule chain is started. Below is a detailed introduction to the Rule Chain Initialization Validator.

Function Overview

Sub-Rule Chains Are Not Allowed to Create Endpoint Components

• Validation Rule: If a sub-rule chain (i.e., a rule chain with the Root attribute set to false) contains an Endpoint component, an error will be triggered.
• Error Message: ErrNotAllowEndpointNode indicates that sub-rule chains are not allowed to create Endpoint components.

Cycle Detection

• Validation Rule: Nodes in the rule chain are not allowed to form cycles. If a cycle is detected, an error will be triggered. (The config.allowCycle switch controls whether cycles are allowed. The default is false, indicating that cycles are not allowed.)
• Error Message: ErrCycleDetected indicates that a cycle reference has been detected in the rule chain.

Custom Validation Rules

Creating Validation Functions

Users can create custom validation functions by defining functions with the following signature:

func(config types.Config, def *types.RuleChain) error

Where:

• config is the configuration information of the rule chain.
• def is the definition of the rule chain.

Registering Validation Rules

Use the Rules.AddRule() method to register custom validation functions with the rule validator. For example:

Rules.AddRule(func(config types.Config, def *types.RuleChain) error {
    if def != nil && len(def.Metadata.Nodes) > 10 {
        return errors.New("the rule chain cannot contain more than 10 nodes")
    }
    return nil
})