> ## Documentation Index
> Fetch the complete documentation index at: https://docs.refold.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Rule Engine

> The Rule Engine allows organizations to define and manage rules for the workflows

Consider an example that you can set up a rule to provision a user in an application only if their type is **Agent** and they have a specific role.

<img height="200" src="https://mintcdn.com/cobalt-55/qu02QklkWCst59D2/images/Config/rule_engine_hosted.png?fit=max&auto=format&n=qu02QklkWCst59D2&q=85&s=296cfe931bbfa2e95ab8ed6996cc8f94" alt="Rule Engine by Refold" data-path="images/Config/rule_engine_hosted.png" />

Managing such rules often involves complexities like fetching user-selected properties or making multiple API calls and the Rule Engine simplifies this process.

## Configuring Rule Engine in Refold

To configure the Rule Engine:

<Steps>
  <Step title="Navigate">
    Navigate to the integration in Refold and click on `Config Portal`.
  </Step>

  <Step title="Create Dataslot">
    Create a new dataslot and set its type to **Rule Engine**.

    <img height="200" src="https://mintcdn.com/cobalt-55/qu02QklkWCst59D2/images/Config/rule_engine.png?fit=max&auto=format&n=qu02QklkWCst59D2&q=85&s=f1136ff722e5bd983e0ccfda84b9a0f7" alt="Rule Engine field type by Refold" data-path="images/Config/rule_engine.png" />
  </Step>
</Steps>

#### Rule Engine Columns

Rule Engine has 3 columns:

* **LHS** - This column lets users select the option that they want to use in the rule.

* **Operator** - This column lets users select the operator that they want to use with the LHS value.

* **RHS** - The value to compare against the LHS field.

After you create a Rule Engine dataslot, you can configure the `Options` that you want to show for the LHS column.

#### Dynamic Columns and Operators using Conditional Code

If your use case requires you to use dynamic options you can select `Use Data Source` and select a workflow that responds with a list of options instead.

The Rule Engine provides a `Conditional Code` block for advanced customizations. This block allows you to dynamically set Operators and RHS values based on the selected LHS.

<img height="200" src="https://mintcdn.com/cobalt-55/qu02QklkWCst59D2/images/Config/rule_dynamic.png?fit=max&auto=format&n=qu02QklkWCst59D2&q=85&s=7d1dfb25888523442ecc7fadbc548862" alt="Dynamic Fields Setup in Rule Engine" data-path="images/Config/rule_dynamic.png" />

A sample code snippet is available in the Rule Engine settings to help you get started.

```JavaScript sample theme={null}
// NOTE: remove this sample code if you don't plan on using any dynamic columns
async function main() {
    // check whether the `lhs` column's value is set to "Region"
    if (lhs === "Region") {
        // define the operators
        const operatorOptions = [
            {
                "name": "Equals To",
                "value": "eq"
            },
            {
                "name": "Not Equals To",
                "value": "neq"
            }
        ]
        // set operator column properties
        cobaltRuleEngine.setColumnProperties("operator", operatorOptions)

        // run the `get_regions` workflow to get the list of regions and set it as options for the rhs column
        const rhsOptions = await cobaltDataSource.getDataSourceResponse("get_regions", {}).return_value
        // set rhs column properties
        cobaltRuleEngine.setColumnProperties("rhs", rhsOptions)

        // log the rhs options. you'll see the logs when you call the `getRuleFieldOptions` method in Cobalt SDK
        console.log("RHS Options", rhsOptions)
    } else {
        // define the operators
        const operatorOptions = [
            {
                "name": "Equals To",
                "value": "eq"
            },
            {
                "name": "Not Equals To",
                "value": "neq"
            },
            {
                "name": "Includes",
                "value": "includes"
            }
        ]
        // set operator column properties
        cobaltRuleEngine.setColumnProperties("operator", operatorOptions)
        // set rhs column properties
        cobaltRuleEngine.setColumnProperties("rhs")
    }
}

main()
```

<Info>
  Use method `cobaltRuleEngine.setColumnProperties` to modify available options dynamically.
</Info>