sriram-nappa / ibm-exercise

Take Home Web Application for IBM

This web application is created as a part of IBM's interview process. The web application filters, sorts and paginates a list of JSON data based on the Query and Request Body sent.

Minimum Requirements:

• nodejs/npm
• Postman or any REST Client

Table of Contents

Usage

Endpoints

Utility Functions

Future Improvements

Usage

• npm install
• npm start (Now the server should have started listening on Port 3000)
• Using curl/postman or any application, send POST/GET requests to the endpoints

Endpoints

1. /api

This route returns all the data in the json file.

2. /api/customers

There are GET and POST calls that can be made to this endpoint:

GET: (Parameters : page, size)

The objects can be paginated based on the user's input from query parameters.

/api/customers?page=:page&size=:size
Eg: http://localhost:3000/api/customers/page=3&size=20 would return 20 objects on page 3. 

If the user doesn't set a size, the default value of size is taken to be 10. Eg: http://localhost:3000/api/customers/page=3 would return 10 objects on page 3.

If the page number is 0 or if it exceeds the maximum number of pages possible for the given query parameters, an empty list is returned.

POST:

 /api/customers   [POST]
 Request body example:
 {
  "filter": [
  		{
			"field": "first_name", 
			"operator": "starts-with", 
			"value": "Aaron"
		},
		{	"field": "age", 
			"operator": "greater-than", 
			"value": 21
		}
	],
  "sort": [
  		{
			"field": "first_name",
			"sortType": "asc"
		},
		{
			"field": "last_name",
			"sortType": "desc"
		},
		{
			"field": "age",
			"sortType": "desc"
		}
	]
}

** Above payload can be used either with sort or filter at a time and also works when both sort/filter is used as mentioned above.**

FilterBy method:

The response can be filtered based on multiple parameters such as starts-with, equals, contains, greater-than, less-than.

Request Body:

Filter is applied only when there exists an object with key "filter" in the request body. The value of "filter" can be a list of objects with keys "field", "operator" and "value". Below keys are case-sensitive

• "field" : The field on which filter has to be applied.

• "operator": The filter operation to be applied on the given field. Look at Utility Functions

• "value" : The value against which the given data has to be filtered.

  Eg:

    {
       "filter": [
        {"field": "first_name", "operator": "starts-with", "value": "Aar"},
        {"field": "age", "operator": "greater-than", "value": 21},
        {"field": "first_name", "operator": "starts-with", "value": "C"},
       ]  
    } 
  

The above filter would return all records that have First Name beginning with "Aar" and last name beginning with "C". All string operations done on the filter is NOT CASE-SENSITIVE.

Any number of filters can be provided or no filters can be provided.

SortBy Method:

RequestBody:

Sorting is applied if there exists an object with key "sort" in the Request Body. The value inside "sort" should be a list of objects with the following keys: "field", "sortingType"

"field" : This is the field on which sorting has to be applied. "sortingType" : The values can be either "asc" or "desc" (lowercase)

Eg:

{
  "sort": [{
      "field": "first_name",
      "sortType": "asc"
    },
    {
      "field": "last_name",
      "sortType": "desc"
    },
    {
      "field": "age",
      "sortType": "desc"
    }
  ]
}

The above example sorts the first_name in ascending order. If there are two first_name with the same value, then it sorts it based on last_name in descending order. If the last names are equal, it sorts based on the age in descending order.

IMPORTANT: A maximum of 3 columns can only be sorted at any given point.

3. /api/addRecord

This route adds a new record to the file.

Example request body:
  {
    "first_name":"Sriram",
    "last_name":"PC",
    "age": 26,
    "gender": "Male",
    "email" : "[email protected]"
  }

Attributes first_name, last_name and age are considered as mandatory fields.

Utility Functions

(Operations for Filter) Below keys are case-sensitive

1. starts-with:

Returns the list of objects which starts with the given string in the field value.

2. contains:

Returns the list of objects which contains given string in the field value.

3. equals:

Returns the list of objects whose value of the given field matches the input given by the user.

4. greater-than:

Returns the list of objects whose value of the given field is greater than the user input.

5. less-than:

Returns the list of objects whose value of the given field is less than the user input.

Future Improvements:

• More utility functions could be added for doing CRUD operations on the data.
• The results could be cached using an in-memory database

Version Details:

Version	Description
1.0.0	A basic web application which has 3 routes to paginate, filter and sort a given set of JSON data

Author:

• Sriram Poondi Chinappa