Web Application Development with MEAN

The expenses module

In this module, we are going to treat functionality related to expenses. This is going to be the main module used by our users in the frontend application, because here they will add new expenses and store them in MongoDB through our backend API.

Expense service

The expense service will implement CRUD operations on expenses and one other important feature of it is getting the balance of expenses. In order to create the expense service, we will follow these steps:

1. Create a file called public/src/expense/expense.service.js.
2. Define the main logic of the service:

   import { Injectable } from 'angular2/core'; import { Http, Response, Headers } from 'angular2/http'; import { Observable } from 'rxjs/Observable'; import { Subject } from 'rxjs/Subject'; ...