JSFiddle - React, Tailwind, and code Playground

HTML

<city-zip ng-app="myapp" city="clientCity" zip="clientZip" required-param="true"></city-zip>

JavaScript

angular.module("myapp", []).directive('cityZip', function() {
    return {
        restrict: 'E',
        templateUrl: '',
        scope: {
            requiredParam:'@'
        },
        link: function(scope, $el, attrs) {
            alert( attrs.requiredParam);
        }
    }
})