fiftyone.pipeline.engines/aspectData.js

Shared base functionality for implementing engines for the 51Degrees Pipeline API

/* *********************************************************************
 * This Original Work is copyright of 51 Degrees Mobile Experts Limited.
 * Copyright 2025 51 Degrees Mobile Experts Limited, Davidson House,
 * Forbury Square, Reading, Berkshire, United Kingdom RG1 3EU.
 *
 * This Original Work is licensed under the European Union Public Licence
 * (EUPL) v.1.2 and is subject to its terms as set out below.
 *
 * If a copy of the EUPL was not distributed with this file, You can obtain
 * one at https://opensource.org/licenses/EUPL-1.2.
 *
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 * amended by the European Commission) shall be deemed incompatible for
 * the purposes of the Work and the provisions of the compatibility
 * clause in Article 5 of the EUPL shall not apply.
 *
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const util = require('util');
const errorMessages = require('./errorMessages');
const ElementData = require('fiftyone.pipeline.core').ElementData;
const MissingPropertyServiceBase = require('./missingPropertyService');

/**
 * @typedef {import('fiftyone.pipeline.core').FlowElement} FlowElement
 * @typedef {import('./missingPropertyService')} MissingPropertyService
 * @typedef {import('fiftyone.pipeline.core').FlowData} FlowData
 */

/**
 * Extension of elementData which allows for a missing property service
 * to be called when an accessed property isn't available.
 * Engines, an extension of flowElements also allow a restricted
 * property list so certain properties can be excluded
 **/
class AspectData extends ElementData {
  /**
   * Constructor for AspectData
   *
   * @param {object} options options object
   * @param {FlowElement} options.flowElement FlowElement the data is for
   * @param {MissingPropertyService} options.missingPropertyService
   * a missing property service to use when the property is in a
   * FlowElement's property list but not in the data
   */
  constructor (
    {
      flowElement, missingPropertyService = new MissingPropertyServiceBase()
    }) {
    super(...arguments);

    if (missingPropertyService) {
      this.missingPropertyService = missingPropertyService;
    }
  }

  /**
   * The aspectData getter runs a series of actions
   * if a property has / has not been found.
   * If it hasn't been found it runs the missing property
   * service if the property is referenced by the
   * flowElement/engine. If the property is found a further
   * check to see if it is restricted by a list passed
   * into the flowElement/engine.
   *
   * @param {string} key the property key to lookup
   * @returns {FlowData} result
   */
  get (key) {
    let result;

    try {
      result = this.getInternal(key);

      if (typeof result === 'undefined') {
        return this.missingPropertyService.check(key, this.flowElement);
      }
    } catch (e) {
      return this.missingPropertyService.check(key, this.flowElement);
    }

    if (this.flowElement.restrictedProperties) {
      if (!this.flowElement.restrictedProperties.includes(key)) {
        throw util.format(errorMessages.propertyExcluded, key);
      }
    }

    return result;
  }
}

module.exports = AspectData;