Scalable Web Challenge

Problem Statement

• Provide 2 http endpoints that accepts JSON base64 encoded binary data on both endpoints
  • /v1/diff//left and /v1/diff//right
• The provided data needs to be diff-ed and the results shall be available on a third end point
  • /v1/diff/
• The results shall provide the following info in JSON format
  • If equal return that
  • If not of equal size just return that
  • If of same size provide insight in where the diffs are, actual diffs are not needed. So mainly offsets + length in the data

Assumptions

1. How our Request and Response Body would look like ?

The input will be a JSON format which will contain a Base64 encoded string. Below are sample Request and Response body :

Request Body:

{
      "data" : "dGVzdGluZyB0aGUgYmFzZTY0"
}

Response Body:

{
       "message" : "Json Data on the Left side saved successfully"
}

2. What are we going to do with the ID?

We will save the ID and its corresponding left and right side into database. When client will call the /v1/diff/, We will use the same id to retrieve the left and right side of data from the database and return the result.

Technologies used

• Java 8
• Spring Boot
• Spring Data
• Spring JPA
• H2 Database
• Maven
• Swagger 2
• Junit & Mockito

Build Requirements

Before being able to build he code you need:

• Maven 3.3+
• Java 1.8

How to run Unit Test and Integration Test?

After you have installed Building requirements tool:

cd scalable-web-json-comparator/scalable-web
mvn test

How to generate Java Docs?

cd scalable-web-json-comparator/scalable-web
mvn javadoc:javadoc

This will create java docs at below location :

cd scalable-web-json-comparator/scalable-web/target/site/apidocs/

How to run code locally?

git clone https://github.com/saurabhoza/scalable-web-json-comparator.git

cd scalable-web-json-comparator/scalable-web

mvn package

java -jar target/scalable-web-1.0.jar

How to test manually?

Endpoints :

• POST /v1/diff/{id}/left
• POST /v1/diff/{id}/right
• GET /v1/diff/{id}

Save left side json :

Request Body

curl -X POST --header 'Content-Type: application/json' --header 'Accept: application/json' -d '{ \ 
   "data": "dGVzdGluZyB0aGUgYmFzZTY0" \ 
 }' 'http://localhost:8080/v1/diff/1/left'

Response Body

{
  "message": "Json Data on the Left side saved successfully"
}

Save right side json :

Request Body

curl -X POST --header 'Content-Type: application/json' --header 'Accept: application/json' -d '{ \ 
   "data": "dGVzdGluZyB0aGUgYmFzZTY0" \ 
 }' 'http://localhost:8080/v1/diff/1/right'

Response Body

{
  "message": "Json Data on the Right side saved successfully"
} 

Get Difference from bothe the JSON :

Request Body

curl -X GET --header 'Accept: application/json' 'http://localhost:8080/v1/diff/1'

Response Body

{
  "message": "Left and Right side of Json data is equal."
}

Rest Documentation with Swagger

• Default host: http://localhost:8080
• This project is using Swagger2 documentation:

http://localhost:8080/v2/api-docs - JSON format of rest documentation http://localhost:8080/swagger-ui.html - UI representation of rest documentation

Achieves

1. Solution was created;
2. Unit tests and Integration tests were created with 97% of code coverage. Code coverage path : https://github.com/saurabhoza/scalable-web-json-comparator/blob/master/Documents/code-coverage-reports/index.html
3. Project is built with zero bugs and Vulnerabilities in Sonar. Sonar Dashboard : https://sonarcloud.io/dashboard?id=scalable-project

Suggestions for improvement

• Dockerizing would be nice, it allows us to test our application across to multiple instances.
• Distributed Cache(Redis) would need if we run application across to multiple instances.
• Authentication will restrict unauthorizes access to this API.