I was apporached by a recruiter through Naukri for a FullStack role in a walk-in drive

Years of Experience :- 4.5 years

Round 1: (Hackerank Coding Round)

1 Database question (can write query in Mysql, Oracle etc...)

Given two tables riders and users, write a db query that joins both and perform a group by sum and return in descending order the users who covered maximum distance.

1 API coding question

Given an GET API that takes input as city name and pagination number, the response data consists of restaurants data pagination wise
Given a city name and maxCost, return all restaurants with food cost <= maxcost

Note :- API response also consists of how many pages are there in total and also you are free to use any library to fetch data from API in the editor.

Round 2: (Backend Round)
1 coding problem (psuedocode is enough)
Given two integers s and n, find maximum n-digit number x such that it should be equal to sum of digits of S
s=12 , n=2
x = 93

• What is sharding and how it works?

• Have you worked on any design patterns?

• How HTTP request works when it sends request to server and how to handle if there is some error before returning respose to users

• Explain about different types of scaling...What is horizontal scaling?

• Explain exceptional handling

• What are microservices and its disadvantages?

• Explain CAP Theorm

• How Django workflow works?

• What are different types of authentication?

• What is JWT authentication, oauth2 and why is JWT Token prefered?

• What is the difference between authorization and authentication?

Round 3: (Frontend Round - React)

• Why is react better than conventional javascript?

• Did u start react with class based components (or) functional based components?

• Let's say you have added an event listiner, how do you remove Event Listener On Unmount?

• What other hooks you have used other than usestate and useeffect?

• Let a=[1,2,3]. how do you copy this array to another array b?

• What is spread operator?

• In react we get a key attribute warning to assign it to elements... why?

• Program for sum of elements in list using reduce

• Difference between foreach and map

• Given a function that accepts any number of integers, return sum of it.

• What is type of an array in javascript?

• Javascript is syncronous or asyncronous?

• settimeout is syncronous or asyncronous?

• How does settimeout knows that after given amount of time, it should execute the codebloack
  inside it?

• How do you call an API in react and where how and where do you call it in the component? and how will make it syncronous? what is async await?

• Explain Flexbox in css

• Layouts in plain html (no bootstrap)

Verdict :- Waiting for feedback