Custom Validators

slug : { 
    required : true, 
    udf : ( value, target ) => {
        if( isNull( arguments.value ) ) return false;
        return qb.from( "content" )
            .where( "slug", arguments.value )
            .when( this.isLoaded(), ( q ) => {
                arguments.q.whereNotIn( "id", this.getId() );
            } )
            .count() == 0;
    }
},

/**
 * Copyright since 2020 by Ortus Solutions, Corp
 * www.ortussolutions.com
 * ---
 * The ColdBox validator interface, all inspired by awesome Hyrule Validation Framework by Dan Vega
 */
interface {

    /**
     * Will check if an incoming value validates
     * @validationResultThe result object of the validation
     * @targetThe target object to validate on
     * @fieldThe field on the target object to validate on
     * @targetValueThe target value to validate
     * @rules The rules imposed on the currently validating field
     */
    boolean function validate(
        required any validationResult,
        required any target,
        required string field,
        any targetValue,
        any validationData,
        struct rules
    );

    /**
     * Get the name of the validator
     */
    string function getName();

}

/**
 * Copyright since 2020 by Ortus Solutions, Corp
 * www.ortussolutions.com
 * ---
 * This validator validates if a value is is less than a maximum number
 */
component accessors="true" singleton {

    property name="name";

    /**
     * Constructor
     */
    MaxValidator function init(){
        variables.name = "Max";
        return this;
    }

    /**
     * Will check if an incoming value validates
     * @validationResultThe result object of the validation
     * @targetThe target object to validate on
     * @fieldThe field on the target object to validate on
     * @targetValueThe target value to validate
     * @validationDataThe validation data the validator was created with
     */
    boolean function validate(
        required any validationResult,
        required any target,
        required string field,
        any targetValue,
        any validationData,
        struct rules
    ){
        // return true if no data to check, type needs a data element to be checked.
        if ( isNull( arguments.targetValue ) || ( isSimpleValue( arguments.targetValue ) && !len( arguments.targetValue ) ) ) {
            return true;
        }

        // Max Tests
        if ( arguments.targetValue <= arguments.validationData ) {
            return true;
        }

        var args = {
            message        : "The '#arguments.field#' value is not less than or equal to #arguments.validationData#",
            field          : arguments.field,
            validationType : getName(),
            rejectedValue  : ( isSimpleValue( arguments.targetValue ) ? arguments.targetValue : "" ),
            validationData : arguments.validationData
        };
        var error = validationResult.newError( argumentCollection = args ).setErrorMetadata( { max : arguments.validationData } );
        validationResult.addError( error );
        return false;
    }

    /**
     * Get the name of the validator
     */
    string function getName(){
        return variables.name;
    }

}

//sample custom validator constraints
    this.constraints = {
        // Approach #1
        myField = {
            required : true, 
            validator : "MyCustomID" 
        },

        // Approach #2
        myField2 = {
            required : true, 
            UniqueInMyDatabase : {
                column : "column_name",
                table : "table_name",
                dsn : "myDatasource"
            },
            MyTimezoneValidator : true
        }
     };