Dr Reddys Path Labs Interview Questions and Answers

Creating a basic POST API with error handling, marshalling, test cases, and HTTP status codes.

• Create a Node.js server using Express framework

• Define a POST route that handles incoming requests

• Implement error handling using try-catch blocks

• Use marshalling to convert data between different formats (e.g. JSON to object)

• Write test cases using a testing framework like Mocha and Chai

• HTTP status codes: 200 (OK), 400 (Bad Request), 401 (Unauthorized), 404 (Not Found), 500 (Internal Se...read more

Use JavaScript methods to determine frequency and delete all occurrences of a specific element in an array of strings.

• Use the reduce method to count the frequency of the specific element in the array.

• Use the filter method to remove all occurrences of the specific element from the array.

Function overriding is a concept where a subclass provides a specific implementation of a method that is already provided by its superclass.

• In JavaScript, function overriding can be achieved by defining a method in a subclass with the same name as a method in its superclass.

• When an object of the subclass calls the overridden method, the subclass's implementation is executed instead of the superclass's.

• This allows for customization and extension of behavior in subclasses while...read more

To create a basic connection to MongoDB, you need to install the MongoDB driver, set up a connection string, and use the MongoClient to connect to the database.

• Install the MongoDB driver using npm install mongodb

• Set up a connection string with the MongoDB URI

• Use the MongoClient to connect to the database

Yes, inheritance in JavaScript is achieved through prototype chaining.

• In JavaScript, objects can inherit properties and methods from other objects through prototype chaining.

• The prototype property allows objects to inherit properties and methods from another object.

• Child objects can access properties and methods of their parent objects through the prototype chain.

• Example: function Animal() {} Animal.prototype.eat = function() { console.log('Eating'); }; function Dog() {} Dog....read more

To interchange 2 variable values without using a temporary variable, you can use arithmetic operations.

• Use addition and subtraction to swap values without a temporary variable.

• Example: If a = 5 and b = 10, you can swap them using a = a + b and b = a - b.

• Make sure to handle potential overflow or underflow when swapping values.

Static is used to declare variables or methods that belong to the class rather than instances of the class.

• Static variables are shared among all instances of a class.

• Static methods can be called without creating an instance of the class.

• Static keyword is used in Java, C++, and other programming languages.

• Example: static int count = 0; // static variable