AngularJS couting the data from factory

Question

I am dealing with annoying problem. I have a angular factory that holds an array of dummy data. And I am grabing this data from factory to my controller and displaying in my view using ng-repeat and it works just fine. But my question is how and where I should write some code to get more information about my data in array, For example If array looks like this:

[
...
{"id":186,"imie":"Bérangère","nazwisko":"West","plec":"Female","adres":"4 Lindbergh Park","zawod":"solution","narodziny":"1927-01-31"},
{"id":187,"imie":"Marylène","nazwisko":"Cooper","plec":"Male","adres":"7 Summit Avenue","zawod":"Profound","narodziny":"1931-09-24"},
{"id":188,"imie":"Gösta","nazwisko":"Nelson","plec":"Female","adres":"5 Corscot Terrace","zawod":"context-sensitive","narodziny":"1954-11-03"},
{"id":189,"imie":"Clélia","nazwisko":"Moore","plec":"Male","adres":"500 Daystar Plaza","zawod":"task-force","narodziny":"1997-01-14"}
...
]

I want to display a total count of users with "plec":"Female" .

Should I write a JavaScript for loop to check my data, or there is an "Angular way" to deal with it?

Answer 1

In Angular, it is best practice to do it in your factory

(function () {
        'use strict';

        angular
            .module('app')
            .factory('MyFactory', MyFactory);

        MyFactory.$inject = ['$http'];

        /* @ngInject */
        function MyFactory($http) {
            var service = {
                dummyUserData: [],
                getUserCountsWhere: getUserCountsWhere
            };

            return service;

            ////////////////

            function getUserCountsWhere(key, value) {
                // key is plec , value is "Female"
                return service.dummyUserData.filter(function(user){
                    return user[key] == value;
                }).length;
            }

        }
    })();

Answer 2

In your factory (or wherever you can access this object) , you can write a function that counts and returns the number of females in your array:

var data = [ ... ];

var countFemales = function() {
    var counter = 0;
    for(var i = 0; i < data.length; i++) {
        if(data[i].plec == "Female") counter++;
    }
    return counter;
}

Answer 3

Try this, using lodash' reduce, which seems a little neater:

function countingMethod() {
  return _.reduce(data, (key, val, acc) => {
    if (data[key]['plec'] === 'Female') {
      acc++;
    }
    return acc;
  }, 0);
}

Or the non-lodash version:

function countingMethod() {
  return data.reduce((key, val, acc) => {
    if (data[key]['plec'] === 'Female') {
      acc++;
    }
    return acc;
  }, 0);
}