Add an arrayToDataTable helper

[sir-dunxalot]

import Ember from 'ember';

/**
Takes an array of data points like [1,2,5,4,5,5,2,1] and
returns the count ({1:2, 2:2, 4:1, 5:3}) of each item for
Google Charts to consume.

@method arrayToDataTable
@param Array dataArray An array of items
@param String [title] An optional column header
@return Object The count of items in the array
*/

export function arrayToDataTable([dataArray = [], title]/*, hash*/) {
  const counter = dataArray.reduce((object, value) => {

    if (!object[value]) {
      object[value] = 1;
    } else {
      object[value]++;
    }

    return object;
  }, {});

  const dataTable = [[title, 'Number of occurences']];

  for (let value in counter) {
    const count = counter[value];

    dataTable.addObject([ value, count ]);
  }

  return dataTable;
}

export default Ember.Helper.helper(arrayToDataTable);

[sir-dunxalot]

Apps now havewindow.google.visualization.arrayToDataTable(data) available and that seems like a better option than this helper.

If you haven't rendered a chart yet, you can load the necessary packages by calling loadPackages() in the GoogleCharts service.

This might be done like:

import Component from '@ember/component';
import { getOwner } from '@ember/application';

export default Component.extend({
  formatData: async function() {
    const service = getOwner(this).lookup('service:google-charts');

    await service.loadPackages();

    /* window.google.visualization should be available now */
  },
});