In the context of security, what does the principle of "least privilege" mean?
- Giving users the fewest privileges necessary to perform their tasks
- Giving users all possible privileges
- Giving administrators fewer privileges than regular users
- Giving privileges based on user seniority
The principle of "least privilege" means giving users the fewest privileges necessary to perform their tasks. This reduces the risk of unauthorized access and potential security breaches. The other options do not align with this security principle.
How can prototype pollution vulnerabilities be mitigated in JavaScript applications?
- Avoid using third-party libraries
- Use strong typing for all variables
- Validate and sanitize user input
- Disable JavaScript prototypes
To mitigate prototype pollution vulnerabilities in JavaScript applications, it's crucial to validate and sanitize user input. This prevents malicious input from corrupting object prototypes. Avoiding third-party libraries and using strong typing are good practices but do not directly address prototype pollution. Disabling prototypes would break core JavaScript functionality.
You are developing a web application that needs to make API requests to a server on a different domain. How would you handle CORS to ensure that your web application can interact with the server without any issues?
- Set up a server-side proxy to forward requests to the other domain.
- Enable CORS on the server by adding appropriate headers to allow cross-origin requests.
- Use JSONP for making cross-domain requests.
- Disable CORS restrictions in the browser settings.
The correct approach is to enable CORS on the server by adding the appropriate headers that allow cross-origin requests. Option A can be a workaround, but it's not the best practice. Option C is an outdated method, and option D is not a recommended security practice.
For optimal performance when querying a large dataset in a NoSQL database, it is crucial to have proper ______ in place.
- Indexing
- Sharding
- Versioning
- Compression
For optimal performance when querying a large dataset in a NoSQL database, it is crucial to have proper indexing in place. Indexes help the database quickly locate and retrieve the data, reducing query response times.
When configuring the static files directory in Express.js, the path specified is relative to the ______ directory.
- current
- project
- root
- parent
When configuring the static files directory in Express.js, the path specified is relative to the root directory of your project. This means that you specify the path from the root of your project's directory structure.
When designing schemas for large-scale systems, the principle of ________ involves dividing the dataset into smaller, more manageable parts.
- Sharding
- Normalization
- Aggregation
- Indexing
The principle of "sharding" involves dividing the dataset into smaller, more manageable parts, typically based on a certain criteria like range or hash, to distribute data across multiple servers or nodes in a distributed system. Sharding is a crucial concept in achieving horizontal scalability in databases.
What type of object is passed as the first argument to the request listener function when creating an HTTP server?
- request
- response
- server
- http
The first argument passed to the request listener function when creating an HTTP server is the request object. This object contains information about the incoming HTTP request, such as headers, URL, and HTTP method. It allows you to read and process client requests.
In Express.js, to skip the remaining route callbacks and pass control to the next middleware function, you can call the ______ function.
- next()
- skip()
- pass()
- continue()
In Express.js, the next() function is used to skip the remaining route callbacks within a middleware function and pass control to the next middleware function in the chain. The other options are not valid functions for this purpose.
What is the significance of implementing Multi-Factor Authentication (MFA) in web applications?
- MFA adds an extra layer of security by requiring users to provide multiple forms of authentication, such as a password and a fingerprint scan.
- MFA simplifies the authentication process by reducing the number of login attempts.
- MFA is primarily used for tracking user behavior and analytics.
- MFA is only useful for protecting against physical security threats.
Implementing Multi-Factor Authentication (MFA) is significant in web applications as it adds an extra layer of security by requiring users to provide multiple forms of authentication, making it harder for unauthorized users to gain access even if they have the user's password. MFA enhances security and helps protect user accounts from various online threats.
You are tasked with developing a system to read and process large files without consuming a lot of memory. How would you utilize streams in Node.js to efficiently read, process, and write the data?
- Use a Readable stream to read the file in chunks, process data asynchronously, and then write to a Writable stream.
- Read the entire file into memory, process it, and then write it back to disk.
- Use a synchronous file reading approach to minimize memory usage.
- Use a single callback function to read and process the entire file sequentially.
To efficiently process large files, you should use a Readable stream to read the file in chunks, process data asynchronously, and then write to a Writable stream. This approach minimizes memory usage and is ideal for handling large files in Node.js.
A common practice for improving error handling in Express.js is to centralize error handling using a ______.
- try-catch block
- catchError middleware
- globalErrorHandler middleware
- throw statement
A common practice for improving error handling in Express.js is to centralize error handling using a globalErrorHandler middleware. This middleware is responsible for handling errors that occur during request processing. While try-catch blocks can be used within routes, they don't centralize error handling, and catchError and throw are not standard middleware constructs in Express.js.
You are developing a media hosting platform where users can upload images and videos. How would you design the file storage and retrieval system to ensure high availability and low latency for users across the globe?
- Use a content delivery network (CDN) to cache and distribute media files to edge servers around the world.
- Store all media files on a single, centralized server to simplify management.
- Use a local file storage system for each region separately.
- Implement a peer-to-peer (P2P) system for users to share media directly.
To ensure high availability and low latency, using a CDN is the recommended approach. CDNs cache content on edge servers located across the globe, reducing the distance between users and the data they request. The other options may lead to latency issues and lower availability.