openmct/platform/features/plot/src/policies/PlotViewPolicy.js

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 * Open MCT, Copyright (c) 2014-2016, United States Government
 * as represented by the Administrator of the National Aeronautics and Space
 * Administration. All rights reserved.
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 * Open MCT is licensed under the Apache License, Version 2.0 (the
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 * http://www.apache.org/licenses/LICENSE-2.0.
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 * License for the specific language governing permissions and limitations
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 *****************************************************************************/

define(
    function () {

        /**
         * Policy preventing the Plot view from being made available for
         * domain objects which have non-numeric telemetry.
         * @implements {Policy.<View, DomainObject>}
         * @constructor
         * @memberof platform/features/plot
         */
        function PlotViewPolicy() {
        }

        function hasNumericTelemetry(domainObject) {
            var telemetry = domainObject &&
                    domainObject.getCapability('telemetry'),
                metadata = telemetry ? telemetry.getMetadata() : {},
                ranges = metadata.ranges || [];

            // Generally, we want to allow Plot for telemetry-providing
            // objects (most telemetry is plottable.) We only want to
            // suppress this for telemetry which only has explicitly
            // non-numeric values.
            return ranges.length === 0 || ranges.some(function (range) {
                    // Assume format is numeric if it is undefined
                    // (numeric telemetry is the common case)
                    return range.format === undefined ||
                        range.format === 'number';
                });
        }

        PlotViewPolicy.prototype.allow = function (view, domainObject) {
            if (view.key === 'plot') {
                return hasNumericTelemetry(domainObject);
            }

            return true;
        };

        return PlotViewPolicy;
    }
);