You are building a high-performance HTTP server using the http module in Node.js and you need to optimize the server for a large number of simultaneous connections. What considerations and implementations would you take into account regarding the http module?

  • Implement clustering with the 'cluster' module
  • Increase the server's memory allocation
  • Use synchronous functions for better performance
  • Disable Keep-Alive connections
To optimize for a large number of simultaneous connections, you can implement clustering using the 'cluster' module, which allows multiple instances of your server to run in parallel. Increasing memory allocation doesn't directly address this issue, synchronous functions can block the event loop, and disabling Keep-Alive connections is not a recommended optimization technique.

You are tasked with implementing a secure and efficient file upload system for a healthcare application, where the confidentiality and integrity of the data are paramount. How would you go about designing this system?

  • Implement end-to-end encryption for file uploads and use secure communication protocols (e.g., HTTPS).
  • Use plain HTTP for file uploads but store files in an encrypted database.
  • Avoid encryption to improve upload speed, and rely on strong server-side security measures.
  • Share decryption keys with trusted third parties for better collaboration.
To ensure the confidentiality and integrity of healthcare data, end-to-end encryption and secure communication protocols (like HTTPS) should be used. Storing files in an encrypted database further enhances security. The other options compromise data security.

What are the critical considerations when implementing encryption for data at rest and data in transit?

  • Encryption keys should be publicly shared
  • Use weak encryption algorithms for better performance
  • Secure key management is essential
  • Encryption is unnecessary for data protection
When implementing encryption for data at rest and data in transit, secure key management is essential. Encryption keys should be carefully protected, and access to them should be restricted. Weak encryption algorithms should be avoided in favor of strong, industry-standard algorithms. Encryption is a crucial component of data protection strategies, ensuring confidentiality and integrity, but it requires thoughtful implementation and management.

Which method in the fs module is used to read the content of a file?

  • readFile
  • openFile
  • readContent
  • loadFile
In the fs module, the readFile method is used to read the content of a file. This method takes the file path and a callback function as parameters and asynchronously reads the file's contents.

What are the considerations for choosing between shallow rendering and mount rendering in a testing environment?

  • Shallow rendering is faster and more isolated, suitable for unit testing; Mount rendering provides a more realistic component tree, suitable for integration testing.
  • Shallow rendering is only suitable for class components; Mount rendering is only suitable for functional components.
  • Shallow rendering should always be preferred to improve test speed; Mount rendering is deprecated.
  • Shallow rendering is best for server-side rendering; Mount rendering is best for client-side rendering.
When choosing between shallow rendering and mount rendering, it's essential to consider the testing goals. Shallow rendering isolates the component being tested and is faster, making it suitable for unit testing. Mount rendering, on the other hand, provides a more realistic component tree, making it suitable for integration testing. The other options contain incorrect information.

In Express.js, the ______ object represents the incoming HTTP request.

  • request
  • req
  • response
  • res
In Express.js, the req object represents the incoming HTTP request. It contains information about the request such as headers, parameters, and body. The request and response options are related to the request and response objects but are not used to represent the incoming request. The res object represents the response, not the request.

Test Driven Development (TDD) primarily emphasizes writing tests ________ the actual implementation code.

  • after
  • during
  • before
  • alongside
Test Driven Development (TDD) emphasizes writing tests before writing the actual implementation code. This approach helps in defining the expected behavior of the code before it is implemented, leading to more robust and testable code. Writing tests during or after implementation goes against the principles of TDD. Writing tests alongside the code may be practiced, but the primary emphasis is on writing tests before implementation.

How are I/O operations, like reading from the file system or network requests, handled by the Event Loop in a non-blocking manner?

  • They are offloaded to worker threads for processing.
  • They are executed sequentially in the main thread.
  • They are delegated to external libraries to handle asynchronously.
  • They are executed concurrently in the main thread using callbacks.
In Node.js, I/O operations are handled by the Event Loop in a non-blocking manner by executing them concurrently in the main thread using callbacks. When an I/O operation is initiated, Node.js registers a callback function to be executed once the operation is complete, allowing the main thread to continue processing other tasks in the meantime.

You are developing a Node.js application that receives binary data from a TCP stream. Which Node.js construct would you use to handle this binary data efficiently?

  • Buffer
  • Array
  • String
  • Number
In Node.js, the Buffer construct is specifically designed for handling binary data efficiently. It allows you to work with raw binary data directly. The other options (Array, String, Number) are not suitable for handling binary data efficiently.

In NoSQL databases like MongoDB, how can you ensure data consistency across distributed databases?

  • Use a two-phase commit protocol.
  • Implement eventual consistency.
  • Leverage distributed transactions.
  • Use primary key constraints.
In NoSQL databases, data consistency across distributed databases is typically ensured by implementing eventual consistency. Two-phase commit protocols and distributed transactions can be complex and might introduce performance bottlenecks. Primary key constraints, while important, don't inherently guarantee distributed consistency.