openmct/platform/containment/src/CompositionPolicy.js

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 * as represented by the Administrator of the National Aeronautics and Space
 * Administration. All rights reserved.
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 * Open MCT Web is licensed under the Apache License, Version 2.0 (the
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/*global define*/

define(
    ['./ContainmentTable'],
    function (ContainmentTable) {
        "use strict";

        /**
         * Defines composition policy as driven by type metadata.
         * @constructor
         * @memberof platform/containment
         */
        function CompositionPolicy($injector) {
            // We're really just wrapping the containment table and rephrasing
            // it as a policy decision.
            var table;

            function getTable() {
                return (table = table || new ContainmentTable(
                    $injector.get('typeService'),
                    $injector.get('capabilityService')
                ));
            }

            return {
                /**
                 * Is the type identified by the candidate allowed to
                 * contain the type described by the context?
                 * @memberof platform/containment.CompositionPolicy#
                 */
                allow: function (candidate, context) {
                    return getTable().canContain(candidate, context);
                }
            };
        }

        return CompositionPolicy;
    }
);