Task Manager (Backend)

This project serves as a backend for the Task Manager application which allows one to create, update, retreive, and delete tasks.

This service is implemented in Node.js using Express. It stores the tasks in a custom-built In-memory database.

Project Setup

If you wish to run this project, the first step is installing Node.js.

Make sure Node.js version 18 LTS or later is installed.
Setup Git and clone this repository to a working directory.
Point a terminal to the project's folder and run npm i in the project root to install dependencies.

After finishing the setup, run npm start to start the development server. By default, server is set to run on port 8000 and can be accessed at http://localhost:8000/.

APIs

Schema

The schema of a task is as follows:

{
  "title": "Mandatory field. Length between 3 - 100 characters.,
  "description": "Mandatory field. Length between 3 - 1000 characters. 
  "completed": false,
  "priority": "medium",
  "id": "1682097744037",
  "createdAt": "2023-04-21T17:22:24.037Z",
  "updatedAt": "2023-04-21T17:22:24.037Z"
}

title & description are mandatory fields & should have a minimum length of 3.
completed & priority are optional fields having a default value of false and "medium" respectively.
id, createdAt & updatedAt are populated by the database.

This application exposes the following endpoints at /api route.

1. GET /tasks

a.

@desc    Get all tasks
@route   GET /api/tasks

b.

@desc    Get selected tasks based on filters specified in the query parameters
@route   /api/tasks?property1=value&property2=value
@param   {string} property (specified in the schema)
@param   {string | number | boolean} value (without quotes)
@example /api/tasks?priority=high&completed=true

c.

@desc    Get tasks sorted on a specified property in ascending / descending order
@route   GET /api/tasks
@body    { sortBy: 'createdAt, orderBy: 'desc' }

2. GET /tasks/:id

@desc    Get a task by id
@route   GET /api/tasks/:id
@param   {number} id

3. GET /tasks/priority/:level

@desc    Get tasks by priority
@route   GET /api/tasks/priority/:level
@param   {enum} (low | medium | high) level

4. CREATE /tasks

@desc    Create a task
@route   POST /api/tasks
@body    { name: string, description: string } name & description are mandatory fields. Fields present in the schema can also be specified (except id, createdAt, updatedAt)

5. UPDATE /tasks/:id

@desc    Update a task by id
@route   PUT /api/tasks/:id
@param   {number} id
@body    { name: string, description: string } Any field present in the schema be specified (except id, createdAt, updatedAt)

6. DELETE /tasks/:id

@desc    Delete a task by id
@route   DELETE /api/tasks/:id
@param   {number} id

For ease of testing, one can use the Postman collection (TaskManager.postman_collection.json) present in the repo.

In-memory database

The database stores data in-memory as JSON. By default, data is indexed by the id. Here's an example of how it looks like:

{
  Tasks: {
    _schema: {
      title: {
        type: 'String',
        trim: true,
        minLength: 3,
        maxLength: 100,
        required: true
      },
      priority: {
        type: 'String',
        enum: ['low', 'medium', 'high'],
        default: 'medium'
      }
    },
    store: {
      1682100568216: {
        "title": "Task 1",
        "description": "Description",
        "completed": true,
        "priority": "medium",
        "id": "1682100568216",
        "createdAt": "2023-04-21T18:09:28.216Z",
        "updatedAt": "2023-04-21T18:09:28.216Z"
      }
    }
  }
}

Database can be instantiated with the name of the collection and the schema. The schema is stored in the _schema property and is used for validating data in POST & PUT operations. It populates id, createdAt, and updatedAt by default for every item.

Besides supporting Create, Read, Update & Delete operations, it can also be queried using the filters - $in, $gt and $lt. Here's an example for the same.

- This will return all the tasks with priority low and medium: { 'priority': { '$in': ['low', 'medium'] } }
- This will return all the items with rating greater than 4 : { 'rating': { '$gt': 4 } }

It supports sorting data on a given property in ascending & descending order. Here's an example for the same.

{ 'sortBy': 'createdAt', 'orderBy': 'asc' }

rishavbharti / taskmanager