elastic-builder/lib/aggregations/metrics-aggregations/scripted-metric-aggregation.js

A JavaScript implementation of the elasticsearch Query DSL

'use strict';

var _classCallCheck2 = require('babel-runtime/helpers/classCallCheck');

var _classCallCheck3 = _interopRequireDefault(_classCallCheck2);

var _createClass2 = require('babel-runtime/helpers/createClass');

var _createClass3 = _interopRequireDefault(_createClass2);

var _possibleConstructorReturn2 = require('babel-runtime/helpers/possibleConstructorReturn');

var _possibleConstructorReturn3 = _interopRequireDefault(_possibleConstructorReturn2);

var _inherits2 = require('babel-runtime/helpers/inherits');

var _inherits3 = _interopRequireDefault(_inherits2);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

var MetricsAggregationBase = require('./metrics-aggregation-base');

var ES_REF_URL = 'https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-metrics-scripted-metric-aggregation.html';

/**
 * A metric aggregation that executes using scripts to provide a metric output.
 *
 * [Elasticsearch reference](https://www.elastic.co/guide/en/elasticsearch/reference/current/search-aggregations-metrics-scripted-metric-aggregation.html)
 *
 * Aggregation that keeps track and returns the minimum value among numeric
 * values extracted from the aggregated documents.
 *
 * @example
 * const agg = esb.scriptedMetricAggregation('profit')
 *     .initScript('params._agg.transactions = []')
 *     .mapScript(
 *         "params._agg.transactions.add(doc.type.value == 'sale' ? doc.amount.value : -1 * doc.amount.value)"
 *     )
 *     .combineScript(
 *         'double profit = 0; for (t in params._agg.transactions) { profit += t } return profit'
 *     )
 *     .reduceScript(
 *         'double profit = 0; for (a in params._aggs) { profit += a } return profit'
 *     );
 *
 * @example
 * // Specify using file scripts
 * const agg = esb.scriptedMetricAggregation('profit')
 *     .initScript(esb.script('file', 'my_init_script'))
 *     .mapScript(esb.script('file', 'my_map_script'))
 *     .combineScript(esb.script('file', 'my_combine_script'))
 *     // script parameters for `init`, `map` and `combine` scripts must be
 *     // specified in a global params object so that
 *     // it can be shared between the scripts
 *     .params({ field: 'amount', _agg: {} })
 *     .reduceScript(esb.script('file', 'my_reduce_script'));
 *
 * @param {string} name The name which will be used to refer to this aggregation.
 *
 * @extends MetricsAggregationBase
 */

var ScriptedMetricAggregation = function (_MetricsAggregationBa) {
    (0, _inherits3.default)(ScriptedMetricAggregation, _MetricsAggregationBa);

    // eslint-disable-next-line require-jsdoc
    function ScriptedMetricAggregation(name) {
        (0, _classCallCheck3.default)(this, ScriptedMetricAggregation);
        return (0, _possibleConstructorReturn3.default)(this, (ScriptedMetricAggregation.__proto__ || Object.getPrototypeOf(ScriptedMetricAggregation)).call(this, name, 'scripted_metric'));
    }

    /**
     * @override
     * @throws {Error} This method cannot be called on ScriptedMetricAggregation
     */


    (0, _createClass3.default)(ScriptedMetricAggregation, [{
        key: 'field',
        value: function field() {
            console.log('Please refer ' + ES_REF_URL);
            throw new Error('field is not supported in ScriptedMetricAggregation');
        }

        /**
         * @override
         * @throws {Error} This method cannot be called on ScriptedMetricAggregation
         */

    }, {
        key: 'script',
        value: function script() {
            console.log('Please refer ' + ES_REF_URL);
            throw new Error('script is not supported in ScriptedMetricAggregation');
        }

        /**
         * @override
         * @throws {Error} This method cannot be called on ScriptedMetricAggregation
         */

    }, {
        key: 'missing',
        value: function missing() {
            console.log('Please refer ' + ES_REF_URL);
            throw new Error('missing is not supported in ScriptedMetricAggregation');
        }

        /**
         * Sets the initialization script.
         *
         * Executed prior to any collection of documents. Allows the aggregation to set up any initial state.
         *
         * @param {string|Script} initScript The initialization script. Can be a string or an Script instance
         * @returns {ScriptedMetricAggregation} returns `this` so that calls can be chained
         */

    }, {
        key: 'initScript',
        value: function initScript(_initScript) {
            this._aggsDef.init_script = _initScript;
            return this;
        }

        /**
         * Sets the map script. This is the only required script.
         *
         * Executed once per document collected.
         * If no combine_script is specified, the resulting state needs to be stored in an object named _agg.
         *
         * @param {string|Script} mapScript The map script. Can be a string or an Script instance
         * @returns {ScriptedMetricAggregation} returns `this` so that calls can be chained
         */

    }, {
        key: 'mapScript',
        value: function mapScript(_mapScript) {
            this._aggsDef.map_script = _mapScript;
            return this;
        }

        /**
         * Sets the combine phase script.
         *
         * Executed once on each shard after document collection is complete.
         * Allows the aggregation to consolidate the state returned from each shard.
         * If a combine_script is not provided the combine phase will return the aggregation variable.
         *
         * @param {string|Script} combineScript The combine script. Can be a string or an Script instance
         * @returns {ScriptedMetricAggregation} returns `this` so that calls can be chained
         */

    }, {
        key: 'combineScript',
        value: function combineScript(_combineScript) {
            this._aggsDef.combine_script = _combineScript;
            return this;
        }

        /**
         * Sets the reduce phase script.
         *
         * Executed once on the coordinating node after all shards have returned their results.
         * The script is provided with access to a variable _aggs
         * which is an array of the result of the combine_script on each shard.
         * If a reduce_script is not provided the reduce phase will return the _aggs variable.
         *
         * @param {string|Script} reduceScript The combine script. Can be a string or an Script instance
         * @returns {ScriptedMetricAggregation} returns `this` so that calls can be chained
         */

    }, {
        key: 'reduceScript',
        value: function reduceScript(_reduceScript) {
            this._aggsDef.reduce_script = _reduceScript;
            return this;
        }

        /**
         * Sets the params for scripts.
         *
         * Optional object whose contents will be passed as variables to
         * the init_script, map_script and combine_script
         *
         * If you specify script parameters then you must specify `"_agg": {}`.
         *
         * @param {Object} params Object passed to init, map and combine script. Default value - `{ "_agg": {} }`
         * @returns {ScriptedMetricAggregation} returns `this` so that calls can be chained
         */

    }, {
        key: 'params',
        value: function params(_params) {
            // TODO: If sure, add validation to see that _agg: {} is present in params
            this._aggsDef.params = _params;
            return this;
        }
    }]);
    return ScriptedMetricAggregation;
}(MetricsAggregationBase);

module.exports = ScriptedMetricAggregation;