graphql-fields-projection-v2/lib/utils.js

- [Why using this?](#why-using-this) - [Install](#install) - [How to](#how-to) - [Example 1: simplest usecase](#example-1-simplest-usecase) - [Example 2: Get more fields](#example-2-get-more-fields) - [Example 3: Get child path](#example-3-get-child

const _ = require('lodash');

/**
 *
 * create the return value
 * @param {[string]} fields input fields
 * @param {string} [returnType='array'] must be either: string, array, or object. Default: array
 * @returns
 */
function createResult(fields, returnType = 'array') {
  return returnType === 'array' ? fields
    : returnType === 'string' ? fields.join(' ')
      : _.reduce(fields, (result, item) => ({ ...result, [item]: 1 }), {});
}

/**
 * Remove Path Collision from input fields
 *
 * @param {[string]} fields input fields
 * @param {string} [returnType='array'] must be either: string, array, or object. Default: array
 * @returns fields projection
 * @author TrongPham KhoaNgo
 */

function removePathCollision(fields = [], returnType = 'array') {
  if (!fields.length) {
    return createResult([], returnType);
  }

  const sortedFields = fields.sort();
  const results = [];

  sortedFields.forEach(field => {
    if (!results.find(x => field.startsWith(`${x}.`))) {
      results.push(field);
    }
  });

  return createResult(results, returnType);

  // return _.reduce(results, (result, item) => ({ ...result, [item]: 1 }), {});
}

module.exports = {
  removePathCollision,
  createResult,
};