WPP Interview Questions and Answers

Node.js uses event-driven architecture to handle asynchronous tasks while synchronous tasks are executed in a blocking manner.

• Node.js uses event loop to handle asynchronous tasks by offloading them to the system, allowing other tasks to continue without waiting.

• Synchronous tasks are executed in a blocking manner, meaning the program waits for each task to complete before moving on to the next one.

• Node.js provides non-blocking I/O operations which allow multiple tasks to be ex...read more

Node.js is single-threaded, but can handle multiple threads using child processes or worker threads.

• Use child processes to run multiple instances of Node.js

• Use worker threads for CPU-intensive tasks

• Leverage the cluster module to create a pool of worker processes

I deploy my application using containerization and continuous integration/continuous deployment (CI/CD) pipelines.

• Utilize Docker to containerize the application for easy deployment and scalability

• Use CI/CD pipelines such as Jenkins or GitLab CI to automate the deployment process

• Deploy to cloud platforms like AWS, Azure, or Google Cloud for reliable hosting

• Implement monitoring and logging tools like Prometheus and ELK stack for performance tracking

Caching can be implemented using RabbitMQ by storing frequently accessed data in memory.

• Set up a RabbitMQ server to act as a message broker

• Publish data to RabbitMQ when it is fetched from the database

• Subscribe to messages in your Node.js application and store the data in memory

• Check the cache before fetching data from the database

Fork creates a new process while spawn launches a new process asynchronously.

• Fork is used to create child processes in Node.js, typically for running separate instances of the same application.

• Spawn is used to launch a new process asynchronously, allowing for communication between the parent and child processes.

• Fork is commonly used in cluster mode for load balancing in Node.js applications.

• Spawn is used for executing external commands or scripts in Node.js.

The order of created and mounted hooks for a child and its parent component in Vue.js.

• The parent component's created hook is called first, followed by the child component's created hook.

• The parent component's mounted hook is called after the child component's mounted hook.

• The order is: parent created -> child created -> child mounted -> parent mounted.

Insertion sort is a simple sorting algorithm that builds the final sorted array one item at a time.

• It starts by comparing the first two elements and swapping them if necessary.

• Then it compares the second and third elements and swaps them if necessary, and so on.

• It continues this process until the entire array is sorted.

• It has a time complexity of O(n^2) in the worst case.

• It is efficient for small data sets or partially sorted data sets.